On Tue, Jun 25, 2019 at 04:14:32PM +0530, sudheer.v wrote: > From: sudheer veliseti <sudheer.open@xxxxxxxxx> > > UART driver for Aspeed's bmc chip AST2500 > > Design approch: > AST2500 has dedicated Uart DMA controller which has 12 sets of Tx and RX channels > connected to UART controller directly. > Since the DMA controller have dedicated buffers and registers, > there would be little benifit in adding DMA framework overhead. > So the software for DMA controller is included within the UART driver itself. > > implementation details: > 'struct uart_8250_port' serial port is populated and registered with 8250_core. > Rx and Tx dma channels are requested from DMA controller software Layer, which > is part of uart driver itself. > Interrupt service routine for DMA controller is the crucial one for Handling all > the tx and rx data. ISRs installed for individual uarts are just dummy,and are helpful > only to report any spurious interrupts in hardware. > > > Signed-off-by: sudheer veliseti <sudheer.open@xxxxxxxxx> > --- > > Changes in v3: > -custom debug replaced by in kerenl dynamic debug: pr_debug > -change-logs added > > .../tty/serial/8250/8250_ast2500_uart_dma.c | 1879 +++++++++++++++++ > 1 file changed, 1879 insertions(+) > create mode 100644 drivers/tty/serial/8250/8250_ast2500_uart_dma.c > > diff --git a/drivers/tty/serial/8250/8250_ast2500_uart_dma.c b/drivers/tty/serial/8250/8250_ast2500_uart_dma.c > new file mode 100644 > index 000000000000..13911a0a745a > --- /dev/null > +++ b/drivers/tty/serial/8250/8250_ast2500_uart_dma.c > @@ -0,0 +1,1879 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DMA UART Driver for ASPEED BMC chip: AST2500 > + * > + * Copyright (C) 2019 sudheer Kumar veliseti, Aspeed technology Inc. > + * <open.sudheer@xxxxxxxxx> > + * > + */ > +#include <linux/io.h> > +#include <linux/irq.h> > +#include <linux/clk.h> > +#include <linux/console.h> > +#include <linux/delay.h> > +#include <linux/dma-mapping.h> > +#include <linux/dma-mapping.h> > +#include <linux/init.h> > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/ioport.h> > +#include <linux/module.h> > +#include <linux/moduleparam.h> > +#include <linux/mutex.h> > +#include <linux/nmi.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/of_device.h> > +#include <linux/of_irq.h> > +#include <linux/of_irq.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > +#include <linux/serial.h> > +#include <linux/serial_8250.h> > +#include <linux/serial_core.h> > +#include <linux/serial_reg.h> > +#include <linux/slab.h> > +#include <linux/tty.h> > +#include <linux/tty_flip.h> Do you really need all of these include files? Seems like a lot... > + > +#include "8250.h" > + > +#define DMA_BUFF_SIZE 0x1000 // 4096 > +#define SDMA_RX_BUFF_SIZE 0x10000 // 65536 We know what 0x1000 and 0x10000 is :) Also, try to line up your defines. > + > +#define SDDMA_RX_FIX 1 > +/* enum ast_uart_chan_op > + * operation codes passed to the DMA code by the user, and also used > + * to inform the current channel owner of any changes to the system state > + */ > + > +enum ast_uart_chan_op { Very odd spacing, add one above the comment and remove the one below. > + AST_UART_DMAOP_TRIGGER, > + AST_UART_DMAOP_STOP, > + AST_UART_DMAOP_PAUSE, > +}; > + > +/* ast_uart_dma_cbfn_t * * buffer callback routine type */ Do not use _t if possible. ANd odd placement of "* *" > +typedef void (*ast_uart_dma_cbfn_t)(void *dev_id, u16 len); > + > +struct ast_sdma_info { > + u8 ch_no; > + u8 direction; > + u8 enable; > + void *priv; > + char *sdma_virt_addr; > + dma_addr_t dma_phy_addr; > + /* cdriver callbacks */ > + ast_uart_dma_cbfn_t callback_fn; /* buffer done callback */ > +}; > + > +#define AST_UART_SDMA_CH 12 > + > +struct ast_sdma_ch { > + struct ast_sdma_info tx_dma_info[AST_UART_SDMA_CH]; > + struct ast_sdma_info rx_dma_info[AST_UART_SDMA_CH]; > +}; > + > +struct ast_sdma { > + void __iomem *reg_base; > + int dma_irq; > + struct ast_sdma_ch *dma_ch; > + struct regmap *map; > +}; > + > + > + > +#define UART_TX_SDMA_EN 0x00 > +#define UART_RX_SDMA_EN 0x04 > +#define UART_SDMA_CONF 0x08 > +#define UART_SDMA_TIMER 0x0C > +#define UART_TX_SDMA_REST 0x20 > +#define UART_RX_SDMA_REST 0x24 > +#define UART_TX_SDMA_IER 0x30 > +#define UART_TX_SDMA_ISR 0x34 > +#define UART_RX_SDMA_IER 0x38 > +#define UART_RX_SDMA_ISR 0x3C > +#define UART_TX_R_POINT(x) (0x40 + (x * 0x20)) > +#define UART_TX_W_POINT(x) (0x44 + (x * 0x20)) > +#define UART_TX_SDMA_ADDR(x) (0x48 + (x * 0x20)) > +#define UART_RX_R_POINT(x) (0x50 + (x * 0x20)) > +#define UART_RX_W_POINT(x) (0x54 + (x * 0x20)) > +#define UART_RX_SDMA_ADDR(x) (0x58 + (x * 0x20)) Please use a tab to line these up. > +/* UART_TX_SDMA_EN-0x00 : UART TX DMA Enable */ > +/* UART_RX_SDMA_EN-0x04 : UART RX DMA Enable */ What are these for? > +#define SDMA_CH_EN(x) (0x1 << (x)) BIT()? > + > +/* UART_SDMA_CONF - 0x08 : Misc, Buffer size */ > +#define SDMA_TX_BUFF_SIZE_MASK (0x3) > +#define SDMA_SET_TX_BUFF_SIZE(x) (x) > +#define SDMA_BUFF_SIZE_1KB (0x0) > +#define SDMA_BUFF_SIZE_4KB (0x1) > +#define SDMA_BUFF_SIZE_16KB (0x2) > +#define SDMA_BUFF_SIZE_64KB (0x3) > +#define SDMA_RX_BUFF_SIZE_MASK (0x3 << 2) > +#define SDMA_SET_RX_BUFF_SIZE(x) (x << 2) > +#define SDMA_TIMEOUT_DIS (0x1 << 4) > + > +/* UART_SDMA_TIMER-0x0C : UART DMA time out timer */ > + > +/* UART_TX_SDMA_IER 0x30 */ > +/* UART_TX_SDMA_ISR 0x34 */ What is this? > + > +#define UART_SDMA11_INT (1 << 11) > +#define UART_SDMA10_INT (1 << 10) > +#define UART_SDMA9_INT (1 << 9) > +#define UART_SDMA8_INT (1 << 8) > +#define UART_SDMA7_INT (1 << 7) > +#define UART_SDMA6_INT (1 << 6) > +#define UART_SDMA5_INT (1 << 5) > +#define UART_SDMA4_INT (1 << 4) > +#define UART_SDMA3_INT (1 << 3) > +#define UART_SDMA2_INT (1 << 2) > +#define UART_SDMA1_INT (1 << 1) > +#define UART_SDMA0_INT (1 << 0) Please use BIT() > + > + > +/* > + * Configuration: > + * share_irqs - whether we pass IRQF_SHARED to request_irq(). This option > + * is unsafe when used on edge-triggered interrupts. > + */ > +static unsigned int share_irqs = SERIAL8250_SHARE_IRQS; > + > +static unsigned int nr_uarts = CONFIG_AST_RUNTIME_DMA_UARTS; > + > + > +#define PASS_LIMIT 256 > + > +#include <asm/serial.h> Why way down here? > + > +#define UART_DMA_NR CONFIG_AST_NR_DMA_UARTS > + > + > +struct ast_uart_priv_data { > + > + unsigned short line; //index of uart port No need for a blank line. > + struct uart_8250_port *up; > + u8 dma_ch; // dma channel number > + struct circ_buf rx_dma_buf; > + struct circ_buf tx_dma_buf; > + dma_addr_t dma_rx_addr; /* Mapped ADMA descr. table */ > + dma_addr_t dma_tx_addr; /* Mapped ADMA descr. table */ > +#ifdef SDDMA_RX_FIX > + struct tasklet_struct rx_tasklet; > +#else > + struct timer_list rx_timer; > +#endif > + struct tasklet_struct tx_tasklet; > + spinlock_t lock; > + int tx_done; > + int tx_count; > +}; > + > + > +static inline struct uart_8250_port * > +to_uart_8250_port(struct uart_port *uart) { > + return container_of(uart, struct uart_8250_port, port); > +} Use a #define for a container_of() macro please. > + > +struct irq_info { > + spinlock_t lock; > + struct uart_8250_port *up; > +}; > + > +static struct irq_info ast_uart_irq[1]; > +static DEFINE_MUTEX(ast_uart_mutex); > + > +/* > + * Here we define the default xmit fifo size used for each type of UART. > + */ > +static const struct serial8250_config uart_config[] = { > + [PORT_UNKNOWN] = { > + .name = "unknown", > + .fifo_size = 1, > + .tx_loadsz = 1, > + }, > + [PORT_8250] = { > + .name = "8250", > + .fifo_size = 1, > + .tx_loadsz = 1, > + }, > + [PORT_16450] = { > + .name = "16450", > + .fifo_size = 1, > + .tx_loadsz = 1, > + }, > + [PORT_16550] = { > + .name = "16550", > + .fifo_size = 1, > + .tx_loadsz = 1, > + }, > + [PORT_16550A] = { > + .name = "16550A", > + .fifo_size = 16, > + .tx_loadsz = 16, > + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 > + | UART_FCR_DMA_SELECT, > + .flags = UART_CAP_FIFO, > + }, > +}; > + > +/* sane hardware needs no mapping */ > +#define map_8250_in_reg(up, offset) (offset) > +#define map_8250_out_reg(up, offset) (offset) Why is this even needed? > + > +// SDMA - software Layer : (previously was in ast-uart-sdma.c) "previously"? > +static inline void ast_uart_sdma_write(struct ast_sdma *sdma, > + u32 val, u32 reg) > +{ > + pr_debug("uart dma write:val:%x,reg:%x\n", val, reg); No need for debugging, use ftrace. > + writel(val, sdma->reg_base + reg); > +} > + > +static inline u32 ast_uart_sdma_read(struct ast_sdma *sdma, u32 reg) > +{ > + return readl(sdma->reg_base + reg); > +} > + > +struct ast_sdma ast_uart_sdma; static? > + > +int ast_uart_rx_sdma_enqueue(u8 ch, dma_addr_t rx_buff) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + pr_debug("ch = %d, rx buff = %x\n", ch, rx_buff); Remove debugging please, use ftrace. > + > + local_irq_save(flags); > + ast_uart_sdma_write(sdma, rx_buff, UART_RX_SDMA_ADDR(ch)); > + local_irq_restore(flags); > + > + return 0; > +} If these functions are not used, why are they here? > + > +int ast_uart_tx_sdma_enqueue(u8 ch, dma_addr_t tx_buff) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + pr_debug("ch = %d, tx buff = %x\n", ch, tx_buff); > + > + local_irq_save(flags); > + ast_uart_sdma_write(sdma, tx_buff, UART_TX_SDMA_ADDR(ch)); > + local_irq_restore(flags); > + > + return 0; > +} > + > +int ast_uart_rx_sdma_ctrl(u8 ch, enum ast_uart_chan_op op) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + struct ast_sdma_info *dma_ch = &(sdma->dma_ch->rx_dma_info[ch]); > + > + pr_debug("RX DMA CTRL [ch %d]\n", ch); Again, please remove. Same thing everywhere in these patches. > + > + local_irq_save(flags); > + > + switch (op) { > + case AST_UART_DMAOP_TRIGGER: > + pr_debug("Trigger\n"); > + dma_ch->enable = 1; > +#ifdef SDDMA_RX_FIX If you can not define this as a build option, then just remove it from here. > +#else > + ast_uart_set_sdma_time_out(0xffff); > +#endif > + // set enable > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_RX_SDMA_EN) | (0x1 << ch), > + UART_RX_SDMA_EN); > + break; Did you run this patch through checkpatch? Please properly indent the case statement blocks. > + case AST_UART_DMAOP_STOP: > + // disable engine > + pr_debug("STOP\n"); > + dma_ch->enable = 0; > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_RX_SDMA_EN) & > + ~(0x1 << ch), > + UART_RX_SDMA_EN); > + // set reset > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_RX_SDMA_REST) | > + (0x1 << ch), > + UART_RX_SDMA_REST); > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_RX_SDMA_REST) & > + ~(0x1 << ch), > + UART_RX_SDMA_REST); > + > + ast_uart_sdma_write(sdma, 0, UART_RX_R_POINT(ch)); > + ast_uart_sdma_write(sdma, dma_ch->dma_phy_addr, UART_RX_SDMA_ADDR(ch)); > + break; > + case AST_UART_DMAOP_PAUSE: > + // disable engine > + dma_ch->enable = 0; > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_RX_SDMA_EN) & > + ~(0x1 << ch), > + UART_RX_SDMA_EN); > + break; > + } > + > + local_irq_restore(flags); > + return 0; > +} > + > +int ast_uart_tx_sdma_ctrl(u8 ch, enum ast_uart_chan_op op) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + struct ast_sdma_info *dma_ch = &(sdma->dma_ch->tx_dma_info[ch]); > + > + pr_debug("TX DMA CTRL [ch %d]\n", ch); > + > + local_irq_save(flags); > + > + switch (op) { > + case AST_UART_DMAOP_TRIGGER: > + pr_debug("TRIGGER : Enable\n"); > + dma_ch->enable = 1; > + // set enable > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_TX_SDMA_EN) | (0x1 << ch), > + UART_TX_SDMA_EN); > + break; > + case AST_UART_DMAOP_STOP: > + pr_debug("STOP : DISABLE & RESET\n"); > + dma_ch->enable = 0; > + // disable engine > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_TX_SDMA_EN) & > + ~(0x1 << ch), > + UART_TX_SDMA_EN); > + // set reset > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_TX_SDMA_REST) | > + (0x1 << ch), > + UART_TX_SDMA_REST); > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_TX_SDMA_REST) & > + ~(0x1 << ch), > + UART_TX_SDMA_REST); > + > + ast_uart_sdma_write(sdma, 0, UART_TX_W_POINT(ch)); > + break; > + case AST_UART_DMAOP_PAUSE: > + pr_debug("PAUSE : DISABLE\n"); > + dma_ch->enable = 0; > + // disable engine > + ast_uart_sdma_write(sdma, ast_uart_sdma_read(sdma, UART_TX_SDMA_EN) & > + ~(0x1 << ch), > + UART_TX_SDMA_EN); > + } > + > + local_irq_restore(flags); > + return 0; > +} > + > +u32 ast_uart_get_tx_sdma_pt(u8 ch) > +{ > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + return ast_uart_sdma_read(sdma, UART_TX_R_POINT(ch)); > +} > + > +int ast_uart_tx_sdma_update(u8 ch, u16 point) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + pr_debug("TX DMA CTRL [ch %d] point %d\n", ch, point); > + local_irq_save(flags); > + ast_uart_sdma_write(sdma, point, UART_TX_W_POINT(ch)); > + local_irq_restore(flags); > + return 0; > +} > + > +int ast_uart_tx_sdma_request(u8 ch, ast_uart_dma_cbfn_t rtn, void *id) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + struct ast_sdma_info *dma_ch = &(sdma->dma_ch->tx_dma_info[ch]); > + > + pr_debug("TX DMA REQUEST ch = %d\n", ch); > + > + local_irq_save(flags); > + > + if (dma_ch->enable) { > + local_irq_restore(flags); > + return -EBUSY; > + } > + dma_ch->priv = id; > + dma_ch->callback_fn = rtn; > + > + // DMA IRQ En > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_TX_SDMA_IER) | (1 << ch), > + UART_TX_SDMA_IER); > + > + local_irq_restore(flags); > + > + return 0; > +} > + > +int ast_uart_rx_sdma_update(u8 ch, u16 point) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + pr_debug("RX DMA CTRL [ch %d] point %x\n", ch, point); > + > + local_irq_save(flags); > + ast_uart_sdma_write(sdma, point, UART_RX_R_POINT(ch)); > + local_irq_restore(flags); > + return 0; > +} > + > +#ifdef SDDMA_RX_FIX > +char *ast_uart_rx_sdma_request(u8 ch, ast_uart_dma_cbfn_t rtn, void *id) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + struct ast_sdma_info *dma_ch = &(sdma->dma_ch->rx_dma_info[ch]); > + > + pr_debug("RX DMA REQUEST ch = %d\n", ch); > + > + local_irq_save(flags); > + > + if (dma_ch->enable) { > + local_irq_restore(flags); > + return 0; > + } > + dma_ch->priv = id; > + > + dma_ch->callback_fn = rtn; > + > + // DMA IRQ En > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_RX_SDMA_IER) | (1 << ch), > + UART_RX_SDMA_IER); > + > + local_irq_restore(flags); > + > + return dma_ch->sdma_virt_addr; > +} > + > +#else > +char *ast_uart_rx_sdma_request(u8 ch, void *id) > +{ > + unsigned long flags; > + struct ast_sdma *sdma = &ast_uart_sdma; > + struct ast_sdma_info *dma_ch = &(sdma->dma_ch->rx_dma_info[ch]); > + > + pr_debug("RX DMA REQUEST ch = %d\n", ch); > + > + local_irq_save(flags); > + > + if (dma_ch->enable) { > + local_irq_restore(flags); > + return -EBUSY; > + } > + dma_ch->priv = id; > + > + local_irq_restore(flags); > + return dma_ch->sdma_virt_addr; > +} > +#endif > + > +u16 ast_uart_get_rx_sdma_pt(u8 ch) > +{ > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + return ast_uart_sdma_read(sdma, UART_RX_W_POINT(ch)); > +} > + > +void ast_uart_set_sdma_time_out(u16 val) > +{ > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + ast_uart_sdma_write(sdma, val, UART_SDMA_TIMER); > +} > + > +static inline void ast_sdma_bufffdone(struct ast_sdma_info *sdma_ch) > +{ > + u32 len; > + struct ast_sdma *sdma = &ast_uart_sdma; > + > + if (sdma_ch->enable == 0) { > + pr_debug("sdma Please check ch_no %x %s!!!!!\n", > + sdma_ch->ch_no, sdma_ch->direction ? "TX" : "RX"); > + if (sdma_ch->direction) { > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_TX_SDMA_EN) > + & ~(0x1 << sdma_ch->ch_no), UART_TX_SDMA_EN); > + } else { > + ast_uart_sdma_write(sdma, > + ast_uart_sdma_read(sdma, UART_RX_SDMA_EN) & > + ~(0x1 << sdma_ch->ch_no), UART_RX_SDMA_EN); > + ast_uart_rx_sdma_update(sdma_ch->ch_no, > + ast_uart_get_rx_sdma_pt(sdma_ch->ch_no)); > + pr_debug("OFFSET : UART_RX_SDMA_EN = %x\n ", > + ast_uart_sdma_read(sdma, UART_RX_SDMA_EN)); > + } > + return; > + } > + > + if (sdma_ch->direction) { > + len = ast_uart_sdma_read(sdma, UART_TX_R_POINT(sdma_ch->ch_no)); > + pr_debug("tx rp %x , wp %x\n", > + ast_uart_sdma_read(sdma, UART_TX_R_POINT(sdma_ch->ch_no)), > + ast_uart_sdma_read(sdma, UART_TX_W_POINT(sdma_ch->ch_no)) > + ); > + } else { > + pr_debug("rx rp %x , wp %x\n", > + ast_uart_sdma_read(sdma, UART_RX_R_POINT(sdma_ch->ch_no)), > + ast_uart_sdma_read(sdma, UART_RX_W_POINT(sdma_ch->ch_no)) > + ); > + len = ast_uart_sdma_read(sdma, UART_RX_W_POINT(sdma_ch->ch_no)); > + } > + > + pr_debug("<dma dwn>: ch[%d] : %s ,len : %d\n", sdma_ch->ch_no, > + sdma_ch->direction ? "tx" : "rx", len); > + > + if (sdma_ch->callback_fn != NULL) > + (sdma_ch->callback_fn)(sdma_ch->priv, len); > +} > + > +static irqreturn_t ast_uart_sdma_isr(int irq, void *dev_id) > +{ > + struct ast_sdma *sdma = (struct ast_sdma *)dev_id; > + > + u32 tx_sts = ast_uart_sdma_read(sdma, UART_TX_SDMA_ISR); > + u32 rx_sts = ast_uart_sdma_read(sdma, UART_RX_SDMA_ISR); > + > + pr_debug("tx sts : %x, rx sts : %x\n", tx_sts, rx_sts); > + > + if ((tx_sts == 0) && (rx_sts == 0)) { > + pr_debug("SDMA IRQ ERROR !!!\n"); > + return IRQ_HANDLED; > + } > + > + if (rx_sts & UART_SDMA0_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA0_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[0])); > + } else if (rx_sts & UART_SDMA1_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA1_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[1])); > + } else if (rx_sts & UART_SDMA2_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA2_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[2])); > + } else if (rx_sts & UART_SDMA3_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA3_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[3])); > + } else if (rx_sts & UART_SDMA4_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA4_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[4])); > + } else if (rx_sts & UART_SDMA5_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA5_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[5])); > + } else if (rx_sts & UART_SDMA6_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA6_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[6])); > + } else if (rx_sts & UART_SDMA7_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA7_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[7])); > + } else if (rx_sts & UART_SDMA8_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA8_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[8])); > + } else if (rx_sts & UART_SDMA9_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA9_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[9])); > + } else if (rx_sts & UART_SDMA10_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA10_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[10])); > + } else if (rx_sts & UART_SDMA11_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA11_INT, UART_RX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->rx_dma_info[11])); > + } else { > + > + } Why a blank else {} ? > + > + if (tx_sts & UART_SDMA0_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA0_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[0])); > + } else if (tx_sts & UART_SDMA1_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA1_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[1])); > + } else if (tx_sts & UART_SDMA2_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA2_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[2])); > + } else if (tx_sts & UART_SDMA3_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA3_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[3])); > + } else if (tx_sts & UART_SDMA4_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA4_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[4])); > + } else if (tx_sts & UART_SDMA5_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA5_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[5])); > + } else if (tx_sts & UART_SDMA6_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA6_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[6])); > + } else if (tx_sts & UART_SDMA7_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA7_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[7])); > + } else if (tx_sts & UART_SDMA8_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA8_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[8])); > + } else if (tx_sts & UART_SDMA9_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA9_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[9])); > + } else if (tx_sts & UART_SDMA10_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA10_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[10])); > + } else if (tx_sts & UART_SDMA11_INT) { > + ast_uart_sdma_write(sdma, UART_SDMA11_INT, UART_TX_SDMA_ISR); > + ast_sdma_bufffdone(&(sdma->dma_ch->tx_dma_info[11])); > + } else { > + } Why a blank else {} ? > + > + return IRQ_HANDLED; > +} > + > +static int ast_uart_sdma_probe(void) > +{ > + int i; > + struct device_node *node; > + int ret; > + struct ast_sdma *sdma = &ast_uart_sdma; > + char *rx_dma_virt_addr; > + dma_addr_t rx_dma_phy_addr; > + > + sdma->dma_ch = kzalloc(sizeof(struct ast_sdma_ch), GFP_KERNEL); > + if (!sdma->dma_ch) > + return -ENOMEM; > + > + // sdma memory mapping > + node = of_find_compatible_node(NULL, NULL, "aspeed,ast-uart-sdma"); > + if (!node) > + return -ENODEV; > + > + sdma->reg_base = of_iomap(node, 0); > + if (IS_ERR(sdma->reg_base)) > + return PTR_ERR(sdma->map); > + rx_dma_virt_addr = dma_alloc_coherent(NULL, > + SDMA_RX_BUFF_SIZE * AST_UART_SDMA_CH, &rx_dma_phy_addr, GFP_KERNEL); Properly indent things, this is impossible to read. > + > + if (!rx_dma_virt_addr) { > + pr_debug("rx_dma_virt_addr Err:dma alloc Failed\n"); > + return -ENOMEM; > + } > + for (i = 0; i < AST_UART_SDMA_CH; i++) { > + // TX ------------------------ > + sdma->dma_ch->tx_dma_info[i].enable = 0; > + sdma->dma_ch->tx_dma_info[i].ch_no = i; > + sdma->dma_ch->tx_dma_info[i].direction = 1; > + ast_uart_sdma_write(sdma, 0, UART_TX_W_POINT(i)); > + // RX ------------------------ > + sdma->dma_ch->rx_dma_info[i].enable = 0; > + sdma->dma_ch->rx_dma_info[i].ch_no = i; > + sdma->dma_ch->rx_dma_info[i].direction = 0; > + sdma->dma_ch->rx_dma_info[i].sdma_virt_addr = > + rx_dma_virt_addr + (SDMA_RX_BUFF_SIZE * i); > + sdma->dma_ch->rx_dma_info[i].dma_phy_addr = > + rx_dma_phy_addr + (SDMA_RX_BUFF_SIZE * i); > + ast_uart_sdma_write(sdma, > + sdma->dma_ch->rx_dma_info[i].dma_phy_addr, > + UART_RX_SDMA_ADDR(i)); > + ast_uart_sdma_write(sdma, 0, UART_RX_R_POINT(i)); > + } > + > + ast_uart_sdma_write(sdma, 0xffffffff, UART_TX_SDMA_REST); > + ast_uart_sdma_write(sdma, 0x0, UART_TX_SDMA_REST); > + > + ast_uart_sdma_write(sdma, 0xffffffff, UART_RX_SDMA_REST); > + ast_uart_sdma_write(sdma, 0x0, UART_RX_SDMA_REST); > + > + ast_uart_sdma_write(sdma, 0, UART_TX_SDMA_EN); > + ast_uart_sdma_write(sdma, 0, UART_RX_SDMA_EN); > + > +#ifdef SDDMA_RX_FIX > + ast_uart_sdma_write(sdma, 0x200, UART_SDMA_TIMER); > +#else > + ast_uart_sdma_write(sdma, 0xffff, UART_SDMA_TIMER); > +#endif > + > + // TX > + ast_uart_sdma_write(sdma, 0xfff, UART_TX_SDMA_ISR); > + ast_uart_sdma_write(sdma, 0, UART_TX_SDMA_IER); > + > + // RX > + ast_uart_sdma_write(sdma, 0xfff, UART_RX_SDMA_ISR); > + ast_uart_sdma_write(sdma, 0, UART_RX_SDMA_IER); > + > + sdma->dma_irq = of_irq_get(node, 0); > + ret = request_irq(sdma->dma_irq, ast_uart_sdma_isr, 0, > + "sdma-intr", sdma); > + if (ret) { > + pr_debug("Unable to get UART SDMA IRQ %x\n", ret); > + return -ENODEV; > + } > + > + ast_uart_sdma_write(sdma, SDMA_SET_TX_BUFF_SIZE(SDMA_BUFF_SIZE_4KB) | > + SDMA_SET_RX_BUFF_SIZE(SDMA_BUFF_SIZE_64KB), > + UART_SDMA_CONF); > + return 0; > +} > + > +// END of SDMA Layer > + > +// UART Driver Layer > + > +static unsigned int ast_serial_in(struct uart_8250_port *up, int offset) > +{ > + offset = map_8250_in_reg(up, offset) << up->port.regshift; > + return readb(up->port.membase + offset); > +} > + > +static void ast_serial_out(struct uart_8250_port *up, int offset, int value) > +{ > + /* Save the offset before it's remapped */ > + offset = map_8250_out_reg(up, offset) << up->port.regshift; > + writeb(value, up->port.membase + offset); > +} > + > +/* > + * We used to support using pause I/O for certain machines. We > + * haven't supported this for a while, but just in case it's badly > + * needed for certain old 386 machines, I've left these #define's > + * in.... It looks like you copied this whole thing from somewhere else, please make it your own and do not leave things in for no good reason. > + */ > +#define serial_inp(up, offset) ast_serial_in(up, offset) > +#define serial_outp(up, offset, value) ast_serial_out(up, offset, value) > + > +/* Uart divisor latch read */ > +static inline int _serial_dl_read(struct uart_8250_port *up) > +{ > + return serial_inp(up, UART_DLL) | serial_inp(up, UART_DLM) << 8; > +} > + > +/* Uart divisor latch write */ > +static inline void _serial_dl_write(struct uart_8250_port *up, int value) > +{ > + serial_outp(up, UART_DLL, value & 0xff); > + serial_outp(up, UART_DLM, value >> 8 & 0xff); > +} > + > +#define serial_dl_read(up) _serial_dl_read(up) > +#define serial_dl_write(up, value) _serial_dl_write(up, value) > + > +static void ast_uart_tx_sdma_tasklet_func(unsigned long data) > +{ > + > + struct ast_uart_priv_data *priv = (struct ast_uart_priv_data *)data; > + struct uart_8250_port *up = priv->up; > + struct circ_buf *xmit = NULL; > + u32 tx_pt; > + > + > + if (!up) > + return; > + xmit = &up->port.state->xmit; > + spin_lock(&up->port.lock); > + priv->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE); > + dma_sync_single_for_device(up->port.dev, priv->dma_tx_addr, > + UART_XMIT_SIZE, DMA_TO_DEVICE); > + tx_pt = ast_uart_get_tx_sdma_pt(priv->dma_ch); > + > + if (tx_pt > xmit->head) { > + if ((tx_pt & 0xfffc) == 0) > + ast_uart_tx_sdma_update(priv->dma_ch, 0xffff); > + else > + ast_uart_tx_sdma_update(priv->dma_ch, 0); > + } else { > + ast_uart_tx_sdma_update(priv->dma_ch, xmit->head); > + } > + ast_uart_tx_sdma_update(priv->dma_ch, xmit->head); > + spin_unlock(&up->port.lock); > +} > + > +static void ast_uart_tx_buffdone(void *dev_id, u16 len) > +{ > + > + struct ast_uart_priv_data *priv = (struct ast_uart_priv_data *)dev_id; > + struct uart_8250_port *up = priv->up; > + struct circ_buf *xmit; > + > + if (!up) > + return; > + xmit = &(up->port.state->xmit); > + > + pr_debug("line[%d] : tx len = % d\n", priv->line, len); > + spin_lock(&up->port.lock); > + xmit->tail = len; > + pr_debug(" line[%d], xmit->head = %d, xmit->tail = % d\n", > + priv->line, xmit->head, xmit->tail); > + > + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + uart_write_wakeup(&up->port); > + > + if (xmit->head != xmit->tail) > + tasklet_schedule(&priv->tx_tasklet); > + > + spin_unlock(&up->port.lock); > +} > + > +#ifdef SDDMA_RX_FIX > +static void ast_uart_rx_sdma_tasklet_func(unsigned long data) > +{ > + struct ast_uart_priv_data *priv = (struct ast_uart_priv_data *)data; > + struct circ_buf *rx_ring = &priv->rx_dma_buf; > + struct tty_port *ttyport; > + int count; > + int copy = 0; > + struct uart_8250_port *up = priv->up; > + > + if (!up) > + return; > + > + ttyport = &up->port.state->port; > + > + pr_debug("line[%d], rx_ring->head = % d, rx_ring->tail = % d\n", > + up->port.line, rx_ring->head, rx_ring->tail); > + spin_lock(&up->port.lock); > + if (rx_ring->head > rx_ring->tail) { > + count = rx_ring->head - rx_ring->tail; > + copy = tty_insert_flip_string(ttyport, > + rx_ring->buf + rx_ring->tail, count); > + } else if (rx_ring->head < rx_ring->tail) { > + count = SDMA_RX_BUFF_SIZE - rx_ring->tail; > + copy = tty_insert_flip_string(ttyport, > + rx_ring->buf + rx_ring->tail, count); > + } else { > + count = 0; > + } > + > + if (copy != count) > + pr_debug(" !!!!!!!!ERROR 111\n"); That's useless. Make it a real error with dev_err() please. > + if (count) { > + rx_ring->tail += count; > + rx_ring->tail &= (SDMA_RX_BUFF_SIZE - 1); > + up->port.icount.rx += count; > + tty_flip_buffer_push(ttyport); > + ast_uart_rx_sdma_update(priv->dma_ch, rx_ring->tail); > + } > + spin_unlock(&up->port.lock); > +} > + > +static void ast_uart_rx_buffdone(void *dev_id, u16 len) > +{ > + struct ast_uart_priv_data *priv = (struct ast_uart_priv_data *)dev_id; > + struct circ_buf *rx_ring = &priv->rx_dma_buf; > + struct uart_8250_port *up = priv->up; > + > + if (!up) > + return; > + pr_debug("line[%d], head = %d,len:%d\n", > + priv->line, priv->rx_dma_buf.head, len); > + spin_lock(&up->port.lock); > + rx_ring->head = len; > + spin_unlock(&up->port.lock); > + tasklet_schedule(&priv->rx_tasklet); > +} > + > +#else > +static void ast_uart_rx_timer_func(unsigned long data) > +{ > + struct ast_uart_priv_data *priv = (struct ast_uart_priv_data *)data; > + struct uart_8250_port *up = priv->up; > + struct tty_port *ttyport; > + struct circ_buf *rx_ring; > + struct tty_struct *tty; > + char flag; > + int count; > + int copy; > + > + > + if (!up) > + return; > + ttyport = &up->port.state->port; > + rx_ring = &up->rx_dma_buf; > + tty = up->port.state->port.tty; > + > + pr_debug("line[%d], rx_ring->head = % d, rx_ring->tail = % d\n", > + up->port.line, rx_ring->head, rx_ring->tail); > + rx_ring->head = ast_uart_get_rx_sdma_pt(priv->dma_ch); > + del_timer(&up->rx_timer); > + > + if (rx_ring->head > rx_ring->tail) { > + ast_uart_set_sdma_time_out(0xffff); > + count = rx_ring->head - rx_ring->tail; > + copy = tty_insert_flip_string(ttyport, > + rx_ring->buf + rx_ring->tail, count); > + } else if (rx_ring->head < rx_ring->tail) { > + ast_uart_set_sdma_time_out(0xffff); > + count = SDMA_RX_BUFF_SIZE - rx_ring->tail; > + copy = tty_insert_flip_string(ttyport, > + rx_ring->buf + rx_ring->tail, count); > + } else { > + count = 0; > + // pr_debug("@@--%s-- ch = 0x%x\n", __func__, ch); > + } > + > + if (copy != count) > + pr_debug(" !!!!!!!!ERROR 111\n"); > + rx_ring->tail += count; > + rx_ring->tail &= (SDMA_RX_BUFF_SIZE - 1); > + > + if (count) { > + //pr_debug("\n count = % d\n", count); > + up->port.icount.rx += count; > + spin_lock(&up->port.lock); > + tty_flip_buffer_push(ttyport); > + spin_unlock(&up->port.lock); > + //pr_debug("update rx_ring->tail % x\n", rx_ring->tail); > + ast_uart_rx_sdma_update(priv->dma_ch, rx_ring->tail); > + priv->workaround = 1; > + } else { > + if (priv->workaround) { > + priv->workaround++; > + if (priv->workaround > 1) > + ast_uart_set_sdma_time_out(0); > + else > + ast_uart_set_sdma_time_out(0xffff); > + } > + } > + add_timer(&up->rx_timer); > +} > +#endif > + > +/* > + * FIFO support. > + */ > +static inline void ast25xx_uart_clear_fifos(struct uart_8250_port *p) > +{ > + serial_outp(p, UART_FCR, UART_FCR_ENABLE_FIFO); > + serial_outp(p, UART_FCR, > + UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); > + serial_outp(p, UART_FCR, 0); > +} > + > +/* > + * This routine is called by rs_init() to initialize a specific serial > + * port. > + */ > +static void autoconfig(struct uart_8250_port *up) > +{ > + unsigned long flags; > + > + pr_debug("line[%d]\n", up->port.line); > + if (!up->port.iobase && !up->port.mapbase && !up->port.membase) > + return; > + > + pr_debug("ttyDMA%d : autoconf (0x%04lx, 0x%p) : ", up->port.line, > + up->port.iobase, up->port.membase); > + > + spin_lock_irqsave(&up->port.lock, flags); > + > + up->capabilities = 0; > + up->bugs = 0; > + > + up->port.type = PORT_16550A; > + up->capabilities |= UART_CAP_FIFO; > + > + up->port.fifosize = uart_config[up->port.type].fifo_size; > + up->capabilities = uart_config[up->port.type].flags; > + up->tx_loadsz = uart_config[up->port.type].tx_loadsz; > + > + if (up->port.type == PORT_UNKNOWN) > + goto out; > + > + /* > + * Reset the UART. > + */ > + ast25xx_uart_clear_fifos(up); > + ast_serial_in(up, UART_RX); > + serial_outp(up, UART_IER, 0); > + > +out: > + spin_unlock_irqrestore(&up->port.lock, flags); > + pr_debug("type=%s\n", uart_config[up->port.type].name); > +} > + > +static inline void __stop_tx(struct uart_8250_port *p) > +{ > + if (p->ier & UART_IER_THRI) { > + p->ier &= ~UART_IER_THRI; > + ast_serial_out(p, UART_IER, p->ier); > + } > +} > + > +static void ast25xx_uart_stop_tx(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + > + pr_debug("line[%d]\n", up->port.line); > + __stop_tx(up); > +} > + > +static void transmit_chars(struct uart_8250_port *up); > + > +static void ast25xx_uart_start_tx(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + struct ast_uart_priv_data *priv = up->port.private_data; > + > + pr_debug("line[%d]\n", port->line); > + tasklet_schedule(&priv->tx_tasklet); > +} > + > +static void ast25xx_uart_stop_rx(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + > + pr_debug("line[%d]\n", port->line); > + up->ier &= ~UART_IER_RLSI; > + up->port.read_status_mask &= ~UART_LSR_DR; > + ast_serial_out(up, UART_IER, up->ier); > +} > + > +static void ast25xx_uart_enable_ms(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + > + pr_debug("line[%d]\n", port->line); > + up->ier |= UART_IER_MSI; > + ast_serial_out(up, UART_IER, up->ier); > +} > + > +static void transmit_chars(struct uart_8250_port *up) > +{ > + struct circ_buf *xmit = &up->port.state->xmit; > + int count; > + > + if (up->port.x_char) { > + serial_outp(up, UART_TX, up->port.x_char); > + up->port.icount.tx++; > + up->port.x_char = 0; > + return; > + } > + if (uart_tx_stopped(&up->port)) { > + ast25xx_uart_stop_tx(&up->port); > + return; > + } > + if (uart_circ_empty(xmit)) { > + __stop_tx(up); > + return; > + } > + > + count = up->tx_loadsz; > + do { > + ast_serial_out(up, UART_TX, xmit->buf[xmit->tail]); > + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); > + up->port.icount.tx++; > + if (uart_circ_empty(xmit)) > + break; > + } while (--count > 0); > + > + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) > + uart_write_wakeup(&up->port); > + > + if (uart_circ_empty(xmit)) > + __stop_tx(up); > +} > + > +static unsigned int check_modem_status(struct uart_8250_port *up) > +{ > + unsigned int status = ast_serial_in(up, UART_MSR); > + > + pr_debug("line[%d]\n", up->port.line); > + status |= up->msr_saved_flags; > + up->msr_saved_flags = 0; > + if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI > + && up->port.state != NULL) { > + if (status & UART_MSR_TERI) > + up->port.icount.rng++; > + if (status & UART_MSR_DDSR) > + up->port.icount.dsr++; > + if (status & UART_MSR_DDCD) > + uart_handle_dcd_change(&up->port, > + status & UART_MSR_DCD); > + if (status & UART_MSR_DCTS) > + uart_handle_cts_change(&up->port, > + status & UART_MSR_CTS); > + > + wake_up_interruptible(&up->port.state->port.delta_msr_wait); > + } > + > + return status; > +} > + > +/* > + * This handles the interrupt from one port. > + */ > +static inline void ast25xx_uart_handle_port(struct uart_8250_port *up) > +{ > + unsigned int status; > + unsigned long flags; > + > + spin_lock_irqsave(&up->port.lock, flags); > + > + status = serial_inp(up, UART_LSR); > + > + pr_debug("status = %x\n", status); > + > + check_modem_status(up); > + if (status & UART_LSR_THRE) > + transmit_chars(up); > + > + spin_unlock_irqrestore(&up->port.lock, flags); > +} > + > +/* > + * This is the serial driver's interrupt routine. > + */ > +static irqreturn_t ast_uart_interrupt(int irq, void *dev_id) > +{ > + struct irq_info *i = dev_id; > + int pass_counter = 0, handled = 0, end = 0; > + > + pr_debug("(%d)-", irq); > + spin_lock(&i->lock); > + > + do { > + struct uart_8250_port *up; > + unsigned int iir; > + > + up = (struct uart_8250_port *)(i->up); > + > + iir = ast_serial_in(up, UART_IIR); > + if (!(iir & UART_IIR_NO_INT)) { > + ast25xx_uart_handle_port(up); > + handled = 1; > + > + } else > + end = 1; > + > + if (pass_counter++ > PASS_LIMIT) { > + /* If we hit this, we're dead. */ > + pr_err("ast-uart-dma:too much work for irq%d\n", irq); > + break; > + } > + } while (end); > + > + spin_unlock(&i->lock); > + > + pr_debug("-(%d)\n", irq); > + > + return IRQ_RETVAL(handled); > +} > + > +static unsigned int ast25xx_uart_tx_empty(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + unsigned long flags; > + unsigned int lsr; > + > + pr_debug("line[%d]\n", up->port.line); > + > + spin_lock_irqsave(&up->port.lock, flags); > + lsr = ast_serial_in(up, UART_LSR); > + up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; > + spin_unlock_irqrestore(&up->port.lock, flags); > + > + return lsr & UART_LSR_TEMT ? TIOCSER_TEMT : 0; > +} > + > +static unsigned int ast25xx_uart_get_mctrl(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + unsigned int status; > + unsigned int ret; > + > + status = check_modem_status(up); > + > + ret = 0; > + if (status & UART_MSR_DCD) > + ret |= TIOCM_CAR; > + if (status & UART_MSR_RI) > + ret |= TIOCM_RNG; > + if (status & UART_MSR_DSR) > + ret |= TIOCM_DSR; > + if (status & UART_MSR_CTS) > + ret |= TIOCM_CTS; > + return ret; > +} > + > +static void ast25xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + unsigned char mcr = 0; > + > + mctrl = 0; > + > + if (mctrl & TIOCM_RTS) > + mcr |= UART_MCR_RTS; > + if (mctrl & TIOCM_DTR) > + mcr |= UART_MCR_DTR; > + if (mctrl & TIOCM_OUT1) > + mcr |= UART_MCR_OUT1; > + if (mctrl & TIOCM_OUT2) > + mcr |= UART_MCR_OUT2; > + if (mctrl & TIOCM_LOOP) > + mcr |= UART_MCR_LOOP; > + > + mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr; > + > + ast_serial_out(up, UART_MCR, mcr); > + > +} > + > +static void ast25xx_uart_break_ctl(struct uart_port *port, int break_state) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + unsigned long flags; > + > + spin_lock_irqsave(&up->port.lock, flags); > + if (break_state == -1) > + up->lcr |= UART_LCR_SBC; > + else > + up->lcr &= ~UART_LCR_SBC; > + ast_serial_out(up, UART_LCR, up->lcr); > + spin_unlock_irqrestore(&up->port.lock, flags); > +} > + > +static int ast25xx_uart_startup(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + // TX DMA > + struct circ_buf *xmit = &up->port.state->xmit; > + struct ast_uart_priv_data *priv = up->port.private_data; > + unsigned long flags; > + unsigned char lsr, iir; > + int retval; > + int irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0; > + > + priv->up = up; > + pr_debug("line[%d]\n", port->line); > + up->capabilities = uart_config[up->port.type].flags; > + up->mcr = 0; > + /* > + * Clear the FIFO buffers and disable them. > + * (they will be reenabled in set_termios()) > + */ > + ast25xx_uart_clear_fifos(up); > + /* > + * Clear the interrupt registers. > + */ > + (void)serial_inp(up, UART_LSR); > + (void)serial_inp(up, UART_RX); > + (void)serial_inp(up, UART_IIR); > + (void)serial_inp(up, UART_MSR); > + > + ast_uart_irq[0].up = up; > + retval = request_irq(up->port.irq, ast_uart_interrupt, irq_flags, > + "ast-uart-dma", ast_uart_irq); > + if (retval) > + return retval; > + > + /* > + * Now, initialize the UART > + */ > + serial_outp(up, UART_LCR, UART_LCR_WLEN8); > + > + spin_lock_irqsave(&up->port.lock, flags); > + up->port.mctrl |= TIOCM_OUT2; > + > + ast25xx_uart_set_mctrl(&up->port, up->port.mctrl); > + > + /* > + * Do a quick test to see if we receive an > + * interrupt when we enable the TX irq. > + */ > + serial_outp(up, UART_IER, UART_IER_THRI); > + lsr = ast_serial_in(up, UART_LSR); > + iir = ast_serial_in(up, UART_IIR); > + serial_outp(up, UART_IER, 0); > + > + if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) { > + if (!(up->bugs & UART_BUG_TXEN)) { > + up->bugs |= UART_BUG_TXEN; > + pr_debug("ttyDMA%d-enabling bad tx status\n", > + port->line); > + } > + } else { > + up->bugs &= ~UART_BUG_TXEN; > + } > + > + spin_unlock_irqrestore(&up->port.lock, flags); > + > + /* > + * Clear the interrupt registers again for luck, and clear the > + * saved flags to avoid getting false values from polling > + * routines or the previous session. > + */ > + serial_inp(up, UART_LSR); > + serial_inp(up, UART_RX); > + serial_inp(up, UART_IIR); > + serial_inp(up, UART_MSR); > + up->lsr_saved_flags = 0; > + up->msr_saved_flags = 0; > + > + // RX DMA > + priv->rx_dma_buf.head = 0; > + priv->rx_dma_buf.tail = 0; > + up->port.icount.rx = 0; > + > + priv->tx_done = 1; > + priv->tx_count = 0; > + > + priv->rx_dma_buf.head = 0; > + priv->rx_dma_buf.tail = 0; > +#ifdef SDDMA_RX_FIX > +#else > + priv->workaround = 0; > +#endif > + // pr_debug("Sending trigger for % x\n", priv->dma_ch); > + ast_uart_rx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_STOP); > + ast_uart_rx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_TRIGGER); > +#ifdef SDDMA_RX_FIX > +#else > + add_timer(&priv->rx_timer); > +#endif > + priv->tx_dma_buf.head = 0; > + priv->tx_dma_buf.tail = 0; > + priv->tx_dma_buf.buf = xmit->buf; > + > + pr_debug("head:0x%x tail:0x%x\n", xmit->head, xmit->tail); > + xmit->head = 0; > + xmit->tail = 0; > + > + priv->dma_tx_addr = dma_map_single(port->dev, priv->tx_dma_buf.buf, > + UART_XMIT_SIZE, DMA_TO_DEVICE); > + > + ast_uart_tx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_STOP); > + ast_uart_tx_sdma_enqueue(priv->dma_ch, priv->dma_tx_addr); > + ast_uart_tx_sdma_update(priv->dma_ch, 0); > + ast_uart_tx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_TRIGGER); > + return 0; > +} > + > +static void ast25xx_uart_shutdown(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + struct ast_uart_priv_data *priv = up->port.private_data; > + unsigned long flags; > + > + pr_debug("line[%d]\n", port->line); > + priv->up = NULL; > + > + up->ier = 0; > + serial_outp(up, UART_IER, 0); > + > + spin_lock_irqsave(&up->port.lock, flags); > + up->port.mctrl &= ~TIOCM_OUT2; > + > + ast25xx_uart_set_mctrl(&up->port, up->port.mctrl); > + spin_unlock_irqrestore(&up->port.lock, flags); > + > + /* > + * Disable break condition and FIFOs > + */ > + ast_serial_out(up, UART_LCR, serial_inp(up, UART_LCR) & ~UART_LCR_SBC); > + ast25xx_uart_clear_fifos(up); > + > + (void)ast_serial_in(up, UART_RX); > + > + ast_uart_rx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_PAUSE); > + ast_uart_tx_sdma_ctrl(priv->dma_ch, AST_UART_DMAOP_PAUSE); > +#ifdef SDDMA_RX_FIX > +#else > + del_timer_sync(&up->rx_timer); > +#endif > + > + // Tx buffer will free by serial_core.c > + free_irq(up->port.irq, ast_uart_irq); > +} > + > +static unsigned int ast25xx_uart_get_divisor(struct uart_port *port, > + unsigned int baud) > +{ > + unsigned int quot; > + > + quot = uart_get_divisor(port, baud); > + > + return quot; > +} > + > +static void ast25xx_uart_set_termios(struct uart_port *port, > + struct ktermios *termios, > + struct ktermios *old) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + unsigned char cval, fcr = 0; > + unsigned long flags; > + unsigned int baud, quot; > + > + switch (termios->c_cflag & CSIZE) { > + case CS5: > + cval = UART_LCR_WLEN5; > + break; > + case CS6: > + cval = UART_LCR_WLEN6; > + break; > + case CS7: > + cval = UART_LCR_WLEN7; > + break; > + default: > + case CS8: > + cval = UART_LCR_WLEN8; > + break; > + } > + > + if (termios->c_cflag & CSTOPB) > + cval |= UART_LCR_STOP; > + if (termios->c_cflag & PARENB) > + cval |= UART_LCR_PARITY; > + if (!(termios->c_cflag & PARODD)) > + cval |= UART_LCR_EPAR; > +#ifdef CMSPAR > + if (termios->c_cflag & CMSPAR) > + cval |= UART_LCR_SPAR; > +#endif > + > + /* > + * Ask the core to calculate the divisor for us. > + */ > + baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); > + quot = ast25xx_uart_get_divisor(port, baud); > + > + if (up->capabilities & UART_CAP_FIFO && up->port.fifosize > 1) { > + if (baud < 2400) > + fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1; > + else > + fcr = uart_config[up->port.type].fcr; > + } > + > + /* > + * Ok, we're now changing the port state. Do it with > + * interrupts disabled. > + */ > + spin_lock_irqsave(&up->port.lock, flags); > + > + /* > + * Update the per-port timeout. > + */ > + uart_update_timeout(port, termios->c_cflag, baud); > + > + up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; > + if (termios->c_iflag & INPCK) > + up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE; > + if (termios->c_iflag & (BRKINT | PARMRK)) > + up->port.read_status_mask |= UART_LSR_BI; > + > + /* > + * Characteres to ignore > + */ > + up->port.ignore_status_mask = 0; > + if (termios->c_iflag & IGNPAR) > + up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; > + if (termios->c_iflag & IGNBRK) { > + up->port.ignore_status_mask |= UART_LSR_BI; > + /* > + * If we're ignoring parity and break indicators, > + * ignore overruns too (for real raw support). > + */ > + if (termios->c_iflag & IGNPAR) > + up->port.ignore_status_mask |= UART_LSR_OE; > + } > + > + /* > + * ignore all characters if CREAD is not set > + */ > + if ((termios->c_cflag & CREAD) == 0) > + up->port.ignore_status_mask |= UART_LSR_DR; > + > + /* > + * CTS flow control flag and modem status interrupts > + */ > + up->ier &= ~UART_IER_MSI; > + if (UART_ENABLE_MS(&up->port, termios->c_cflag)) > + up->ier |= UART_IER_MSI; > + > + ast_serial_out(up, UART_IER, up->ier); > + > + serial_outp(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */ > + > + serial_dl_write(up, quot); > + > + /* > + * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR > + * is written without DLAB set, this mode will be disabled. > + */ > + > + serial_outp(up, UART_LCR, cval); /* reset DLAB */ > + up->lcr = cval; /* Save LCR */ > + if (fcr & UART_FCR_ENABLE_FIFO) { > + /* emulated UARTs (Lucent Venus 167x) need two steps */ > + serial_outp(up, UART_FCR, UART_FCR_ENABLE_FIFO); > + } > + serial_outp(up, UART_FCR, fcr); /* set fcr */ > + ast25xx_uart_set_mctrl(&up->port, up->port.mctrl); > + spin_unlock_irqrestore(&up->port.lock, flags); > + /* Don't rewrite B0 */ > + if (tty_termios_baud_rate(termios)) > + tty_termios_encode_baud_rate(termios, baud, baud); > +} > + > +/* > + * Resource handling. > + */ > +static int ast25xx_uart_request_std_resource(struct uart_8250_port *up) > +{ > + unsigned int size = 8 << up->port.regshift; > + int ret = 0; > + > + if (!up->port.mapbase) > + return ret; > + > + if (!request_mem_region(up->port.mapbase, size, "ast-uart-dma")) { > + ret = -EBUSY; > + return ret; > + } > + > + if (up->port.flags & UPF_IOREMAP) { > + up->port.membase = ioremap_nocache(up->port.mapbase, size); > + if (!up->port.membase) { > + release_mem_region(up->port.mapbase, size); > + ret = -ENOMEM; > + return ret; > + } > + } > + return ret; > +} > + > +static void ast25xx_uart_release_std_resource(struct uart_8250_port *up) > +{ > + unsigned int size = 8 << up->port.regshift; > + > + if (!up->port.mapbase) > + return; > + > + if (up->port.flags & UPF_IOREMAP) { > + iounmap(up->port.membase); > + up->port.membase = NULL; > + } > + > + release_mem_region(up->port.mapbase, size); > +} > + > +static void ast25xx_uart_release_port(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + > + ast25xx_uart_release_std_resource(up); > +} > + > +static int ast25xx_uart_request_port(struct uart_port *port) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + int ret; > + > + ret = ast25xx_uart_request_std_resource(up); > + if (ret == 0) > + ast25xx_uart_release_std_resource(up); > + > + return ret; > +} > + > +static void ast25xx_uart_config_port(struct uart_port *port, int flags) > +{ > + struct uart_8250_port *up = to_uart_8250_port(port); > + int ret; > + > + /* > + * Find the region that we can probe for. This in turn > + * tells us whether we can probe for the type of port. > + */ > + ret = ast25xx_uart_request_std_resource(up); > + if (ret < 0) > + return; > + > + if (flags & UART_CONFIG_TYPE) > + autoconfig(up); > + > + if (up->port.type == PORT_UNKNOWN) > + ast25xx_uart_release_std_resource(up); > +} > + > +static int ast25xx_uart_verify_port(struct uart_port *port, > + struct serial_struct *ser) > +{ > + return 0; > +} > + > +static const char *ast25xx_uart_type(struct uart_port *port) > +{ > + int type = port->type; > + > + if (type >= ARRAY_SIZE(uart_config)) > + type = 0; > + return uart_config[type].name; > +} > + > + > + > +static unsigned int ast25xx_uart_serial_in(struct uart_port *port, int offset) > +{ > + offset = offset << port->regshift; > + return readb(port->membase + offset); > + > +} > + > + > +static void ast25xx_uart_serial_out(struct uart_port *port, > + int offset, int value) > +{ > + offset = offset << port->regshift; > + writeb(value, port->membase + offset); > +} > + > +static const struct uart_ops ast25xx_uart_pops = { > + .tx_empty = ast25xx_uart_tx_empty, > + .set_mctrl = ast25xx_uart_set_mctrl, > + .get_mctrl = ast25xx_uart_get_mctrl, > + .stop_tx = ast25xx_uart_stop_tx, > + .start_tx = ast25xx_uart_start_tx, > + .stop_rx = ast25xx_uart_stop_rx, > + .enable_ms = ast25xx_uart_enable_ms, > + .break_ctl = ast25xx_uart_break_ctl, > + .startup = ast25xx_uart_startup, > + .shutdown = ast25xx_uart_shutdown, > + .set_termios = ast25xx_uart_set_termios, > + .type = ast25xx_uart_type, > + .release_port = ast25xx_uart_release_port, > + .request_port = ast25xx_uart_request_port, > + .config_port = ast25xx_uart_config_port, > + .verify_port = ast25xx_uart_verify_port, > +}; > + > + > + > +/* > + * Register a set of serial devices attached to a platform device. The > + * list is terminated with a zero flags entry, which means we expect > + * all entries to have at least UPF_BOOT_AUTOCONF set. > + */ > +struct clk *clk; static? > + > +static int ast25xx_uart_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct ast_uart_priv_data *priv; > + struct uart_8250_port port_8250; > + struct uart_8250_port *up; > + int ret; > + u32 read, dma_channel = 0; > + struct resource *res; > + > + if (UART_XMIT_SIZE > DMA_BUFF_SIZE) > + pr_debug("UART_XMIT_SIZE > DMA_BUFF_SIZE : Please Check\n"); > + > + priv = (struct ast_uart_priv_data *)devm_kzalloc(&pdev->dev, > + sizeof(struct ast_uart_priv_data), GFP_KERNEL); > + if (priv == NULL) > + return -ENOMEM; > + > + up = &port_8250; > + memset(up, 0, sizeof(struct uart_8250_port)); > + up->port.flags = UPF_IOREMAP; > + > + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); > + if (res == NULL) { > + dev_err(&pdev->dev, "IRQ resource not found"); > + return -ENODEV; > + } > + up->port.irq = res->start; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) { > + dev_err(&pdev->dev, "Register base not found"); > + return -ENODEV; > + } > + up->port.mapbase = res->start; > + > + ret = ast25xx_uart_request_std_resource(up); > + if (ret) { > + dev_err(&pdev->dev, "ioremap_nocache Failed"); > + return ret; > + } > + > + clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(clk)) > + dev_err(&pdev->dev, "missing controller clock"); > + > + ret = clk_prepare_enable(clk); > + if (ret) > + dev_err(&pdev->dev, "failed to enable DMA UART Clk"); > + > + up->port.uartclk = clk_get_rate(clk); > + > + if (of_property_read_u32(np, "reg-shift", &read) == 0) > + up->port.regshift = read; > + if (of_property_read_u32(np, "dma-channel", &read) == 0) { > + dma_channel = read; > + priv->dma_ch = dma_channel; > + } > + up->port.iotype = UPIO_MEM; > + up->port.flags |= UPF_BOOT_AUTOCONF | UPF_SKIP_TEST; > + up->port.dev = &pdev->dev; > + if (share_irqs) > + up->port.flags |= UPF_SHARE_IRQ; > + up->port.fifosize = uart_config[up->port.type].fifo_size; > + up->port.type = PORT_16550; > + up->port.iotype = UPIO_MEM; > + up->port.flags = UPF_FIXED_TYPE; > + up->port.startup = ast25xx_uart_startup; > + up->port.shutdown = ast25xx_uart_shutdown; > + up->port.set_termios = ast25xx_uart_set_termios; > + up->port.set_mctrl = ast25xx_uart_set_mctrl; > + up->port.serial_in = ast25xx_uart_serial_in; > + up->port.serial_out = ast25xx_uart_serial_out; > + up->capabilities = uart_config[up->port.type].flags; > + up->tx_loadsz = uart_config[up->port.type].tx_loadsz; > + up->capabilities |= UART_CAP_FIFO; > + > + up->port.private_data = priv; > + > + ret = serial8250_register_8250_port(up); > + if (ret < 0) { > + dev_err(&pdev->dev, > + "unable to registr port (IO%lx MEM%llx IRQ%d):%d\n", > + up->port.iobase, (unsigned long long)up->port.mapbase, > + up->port.irq, ret); > + return ret; > + } > + priv->line = ret; > + > + tasklet_init(&priv->tx_tasklet, ast_uart_tx_sdma_tasklet_func, > + (unsigned long)priv); > +#ifdef SDDMA_RX_FIX > + tasklet_init(&priv->rx_tasklet, ast_uart_rx_sdma_tasklet_func, > + (unsigned long)priv); > +#else > + uart->rx_timer.data = (unsigned long)port; > + uart->rx_timer.expires = jiffies + (HZ); > + uart->rx_timer.function = ast_uart_rx_timer_func; > + init_timer(&priv->rx_timer); > +#endif > + > +//DMA request > +#ifdef SDDMA_RX_FIX > + priv->rx_dma_buf.buf = > + ast_uart_rx_sdma_request(priv->dma_ch, ast_uart_rx_buffdone, > + priv); > + if (priv->rx_dma_buf.buf < 0) { > + pr_debug("Error : failed to get rx dma channel[%d]\n", > + priv->dma_ch); > + return -EBUSY; > +} > +#else > + priv->rx_dma_buf.buf = ast_uart_rx_sdma_request( > + priv->dma_ch, priv); > + if (priv->rx_dma_buf.buf < 0) { > + pr_debug("Error : failed to get rx dma channel[%d]\n", > + priv->dma_ch); > + return -EBUSY; > + } > +#endif > + if (ast_uart_tx_sdma_request( > + priv->dma_ch, ast_uart_tx_buffdone, priv) < 0) { > + pr_debug("Error : failed to get tx dma channel[%d]\n", > + priv->dma_ch); > + return -EBUSY; > + } > + > + platform_set_drvdata(pdev, priv); > + return 0; > +} > + > +/* > + * Remove serial ports registered against a platform device. > + */ > +static int ast25xx_uart_remove(struct platform_device *pdev) > +{ > + struct ast_uart_priv_data *priv; > + > + priv = platform_get_drvdata(pdev); > + serial8250_unregister_port(priv->line); > + return 0; > +} > + > +static int ast25xx_uart_suspend(struct platform_device *pdev, > + pm_message_t state) > +{ > + struct ast_uart_priv_data *priv; > + > + priv = platform_get_drvdata(pdev); > + serial8250_suspend_port(priv->line); > + return 0; > +} > + > +static int ast25xx_uart_resume(struct platform_device *pdev) > +{ > + struct ast_uart_priv_data *priv; > + > + priv = platform_get_drvdata(pdev); > + serial8250_resume_port(priv->line); > + return 0; > +} > + > +static const struct of_device_id ast_serial_dt_ids[] = { > + { .compatible = "aspeed,ast-sdma-uart", }, > + { /* sentinel */ } > +}; > + > +static struct platform_driver ast25xx_uart_driver = { > + .probe = ast25xx_uart_probe, > + .remove = ast25xx_uart_remove, > + .suspend = ast25xx_uart_suspend, > + .resume = ast25xx_uart_resume, > + .driver = { > + .name = "ast-uart-dma", > + .of_match_table = of_match_ptr(ast_serial_dt_ids), Indent properly. This whole file looks like it can be made smaller, please remove the unneeded and unused code for your next submission. thanks, greg k-h