On Sat, 4 Apr 2020, at 02:58, Eddie James wrote: > The XDMA engine embedded in the AST2500 and AST2600 SOCs performs PCI > DMA operations between the SOC (acting as a BMC) and a host processor > in a server. > > This commit adds a driver to control the XDMA engine and adds functions > to initialize the hardware and memory and start DMA operations. > > Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx> > Reviewed-by: Andrew Jeffery <andrew@xxxxxxxx> > --- > Changes since v6: > - Switch to use a chunk of reserved memory from the devicetree rather than > simply reading the address and size > - Add PCI-E root complex reset > - Fix buffer overrun in aspeed_xdma_start > - Switch to usleep_range with a smaller time than the old msleep(10) because > that time is for toggling the clock, which we don't do during reset and > should be done by the clock driver anyway > - Set some additional bit in the SCU necessary for XDMA to work > - Refactor probe error handling near the end > > MAINTAINERS | 2 + > drivers/soc/aspeed/Kconfig | 8 + > drivers/soc/aspeed/Makefile | 1 + > drivers/soc/aspeed/aspeed-xdma.c | 842 +++++++++++++++++++++++++++++++ > include/uapi/linux/aspeed-xdma.h | 38 ++ > 5 files changed, 891 insertions(+) > create mode 100644 drivers/soc/aspeed/aspeed-xdma.c > create mode 100644 include/uapi/linux/aspeed-xdma.h > > diff --git a/MAINTAINERS b/MAINTAINERS > index dcc0907b2aa5..e417a15f33a8 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -2776,6 +2776,8 @@ M: Eddie James <eajames@xxxxxxxxxxxxx> > L: linux-aspeed@xxxxxxxxxxxxxxxx (moderated for non-subscribers) > S: Maintained > F: Documentation/devicetree/bindings/soc/aspeed/xdma.txt > +F: drivers/soc/aspeed/aspeed-xdma.c > +F: include/uapi/linux/aspeed-xdma.h > > ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS > M: Corentin Chary <corentin.chary@xxxxxxxxx> > diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig > index 323e177aa74d..2a6c16f9e50b 100644 > --- a/drivers/soc/aspeed/Kconfig > +++ b/drivers/soc/aspeed/Kconfig > @@ -29,4 +29,12 @@ config ASPEED_P2A_CTRL > ioctl()s, the driver also provides an interface for userspace mappings to > a pre-defined region. > > +config ASPEED_XDMA > + tristate "Aspeed XDMA Engine Driver" > + depends on SOC_ASPEED && REGMAP && MFD_SYSCON && HAS_DMA > + help > + Enable support for the Aspeed XDMA Engine found on the Aspeed AST2XXX > + SOCs. The XDMA engine can perform automatic PCI DMA operations > + between the AST2XXX (acting as a BMC) and a host processor. > + > endmenu > diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile > index b64be47f2b1f..977b046dfb73 100644 > --- a/drivers/soc/aspeed/Makefile > +++ b/drivers/soc/aspeed/Makefile > @@ -2,3 +2,4 @@ > obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o > obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o > obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o > +obj-$(CONFIG_ASPEED_XDMA) += aspeed-xdma.o > diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c > new file mode 100644 > index 000000000000..7503246c14d5 > --- /dev/null > +++ b/drivers/soc/aspeed/aspeed-xdma.c > @@ -0,0 +1,842 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +// Copyright IBM Corp 2019 > + > +#include <linux/aspeed-xdma.h> > +#include <linux/bitfield.h> > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/device.h> > +#include <linux/dma-mapping.h> > +#include <linux/fs.h> > +#include <linux/genalloc.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/jiffies.h> > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/of_device.h> > +#include <linux/of_reserved_mem.h> > +#include <linux/platform_device.h> > +#include <linux/poll.h> > +#include <linux/regmap.h> > +#include <linux/reset.h> > +#include <linux/slab.h> > +#include <linux/spinlock.h> > +#include <linux/string.h> > +#include <linux/uaccess.h> > +#include <linux/wait.h> > +#include <linux/workqueue.h> > + > +#define DEVICE_NAME "aspeed-xdma" > + > +#define SCU_AST2600_MISC_CTRL 0x0c0 > +#define SCU_AST2600_MISC_CTRL_XDMA_BMC BIT(8) > + > +#define SCU_AST2500_PCIE_CONF 0x180 > +#define SCU_AST2600_PCIE_CONF 0xc20 > +#define SCU_PCIE_CONF_VGA_EN BIT(0) > +#define SCU_PCIE_CONF_VGA_EN_MMIO BIT(1) > +#define SCU_PCIE_CONF_VGA_EN_LPC BIT(2) > +#define SCU_PCIE_CONF_VGA_EN_MSI BIT(3) > +#define SCU_PCIE_CONF_VGA_EN_MCTP BIT(4) > +#define SCU_PCIE_CONF_VGA_EN_IRQ BIT(5) > +#define SCU_PCIE_CONF_VGA_EN_DMA BIT(6) > +#define SCU_PCIE_CONF_BMC_EN BIT(8) > +#define SCU_PCIE_CONF_BMC_EN_MMIO BIT(9) > +#define SCU_PCIE_CONF_BMC_EN_MSI BIT(11) > +#define SCU_PCIE_CONF_BMC_EN_MCTP BIT(12) > +#define SCU_PCIE_CONF_BMC_EN_IRQ BIT(13) > +#define SCU_PCIE_CONF_BMC_EN_DMA BIT(14) > + > +#define SCU_AST2500_BMC_CLASS_REV 0x19c > +#define SCU_AST2600_BMC_CLASS_REV 0xc68 > +#define SCU_BMC_CLASS_REV_XDMA 0xff000001 > + > +#define XDMA_CMDQ_SIZE PAGE_SIZE > +#define XDMA_NUM_CMDS \ > + (XDMA_CMDQ_SIZE / sizeof(struct aspeed_xdma_cmd)) > + > +/* Aspeed specification requires 100us after disabling the reset */ > +#define XDMA_ENGINE_SETUP_TIME_MAX_US 1000 > +#define XDMA_ENGINE_SETUP_TIME_MIN_US 100 > + > +#define XDMA_CMD_AST2500_PITCH_SHIFT 3 > +#define XDMA_CMD_AST2500_PITCH_BMC GENMASK_ULL(62, 51) > +#define XDMA_CMD_AST2500_PITCH_HOST GENMASK_ULL(46, 35) > +#define XDMA_CMD_AST2500_PITCH_UPSTREAM BIT_ULL(31) > +#define XDMA_CMD_AST2500_PITCH_ADDR GENMASK_ULL(29, 4) > +#define XDMA_CMD_AST2500_PITCH_ID BIT_ULL(0) > +#define XDMA_CMD_AST2500_CMD_IRQ_EN BIT_ULL(31) > +#define XDMA_CMD_AST2500_CMD_LINE_NO GENMASK_ULL(27, 16) > +#define XDMA_CMD_AST2500_CMD_IRQ_BMC BIT_ULL(15) > +#define XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT 4 > +#define XDMA_CMD_AST2500_CMD_LINE_SIZE \ > + GENMASK_ULL(14, XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT) > +#define XDMA_CMD_AST2500_CMD_ID BIT_ULL(1) > + > +#define XDMA_CMD_AST2600_PITCH_BMC GENMASK_ULL(62, 48) > +#define XDMA_CMD_AST2600_PITCH_HOST GENMASK_ULL(46, 32) > +#define XDMA_CMD_AST2600_PITCH_ADDR GENMASK_ULL(30, 0) > +#define XDMA_CMD_AST2600_CMD_64_EN BIT_ULL(40) > +#define XDMA_CMD_AST2600_CMD_IRQ_BMC BIT_ULL(37) > +#define XDMA_CMD_AST2600_CMD_IRQ_HOST BIT_ULL(36) > +#define XDMA_CMD_AST2600_CMD_UPSTREAM BIT_ULL(32) > +#define XDMA_CMD_AST2600_CMD_LINE_NO GENMASK_ULL(27, 16) > +#define XDMA_CMD_AST2600_CMD_LINE_SIZE GENMASK_ULL(14, 0) > +#define XDMA_CMD_AST2600_CMD_MULTILINE_SIZE GENMASK_ULL(14, 12) > + > +#define XDMA_AST2500_QUEUE_ENTRY_SIZE 4 > +#define XDMA_AST2500_HOST_CMDQ_ADDR0 0x00 > +#define XDMA_AST2500_HOST_CMDQ_ENDP 0x04 > +#define XDMA_AST2500_HOST_CMDQ_WRITEP 0x08 > +#define XDMA_AST2500_HOST_CMDQ_READP 0x0c > +#define XDMA_AST2500_BMC_CMDQ_ADDR 0x10 > +#define XDMA_AST2500_BMC_CMDQ_ENDP 0x14 > +#define XDMA_AST2500_BMC_CMDQ_WRITEP 0x18 > +#define XDMA_AST2500_BMC_CMDQ_READP 0x1c > +#define XDMA_BMC_CMDQ_READP_RESET 0xee882266 > +#define XDMA_AST2500_CTRL 0x20 > +#define XDMA_AST2500_CTRL_US_COMP BIT(4) > +#define XDMA_AST2500_CTRL_DS_COMP BIT(5) > +#define XDMA_AST2500_CTRL_DS_DIRTY BIT(6) > +#define XDMA_AST2500_CTRL_DS_SIZE_256 BIT(17) > +#define XDMA_AST2500_CTRL_DS_TIMEOUT BIT(28) > +#define XDMA_AST2500_CTRL_DS_CHECK_ID BIT(29) > +#define XDMA_AST2500_STATUS 0x24 > +#define XDMA_AST2500_STATUS_US_COMP BIT(4) > +#define XDMA_AST2500_STATUS_DS_COMP BIT(5) > +#define XDMA_AST2500_STATUS_DS_DIRTY BIT(6) > +#define XDMA_AST2500_INPRG_DS_CMD1 0x38 > +#define XDMA_AST2500_INPRG_DS_CMD2 0x3c > +#define XDMA_AST2500_INPRG_US_CMD00 0x40 > +#define XDMA_AST2500_INPRG_US_CMD01 0x44 > +#define XDMA_AST2500_INPRG_US_CMD10 0x48 > +#define XDMA_AST2500_INPRG_US_CMD11 0x4c > +#define XDMA_AST2500_INPRG_US_CMD20 0x50 > +#define XDMA_AST2500_INPRG_US_CMD21 0x54 > +#define XDMA_AST2500_HOST_CMDQ_ADDR1 0x60 > +#define XDMA_AST2500_VGA_CMDQ_ADDR0 0x64 > +#define XDMA_AST2500_VGA_CMDQ_ENDP 0x68 > +#define XDMA_AST2500_VGA_CMDQ_WRITEP 0x6c > +#define XDMA_AST2500_VGA_CMDQ_READP 0x70 > +#define XDMA_AST2500_VGA_CMD_STATUS 0x74 > +#define XDMA_AST2500_VGA_CMDQ_ADDR1 0x78 > + > +#define XDMA_AST2600_QUEUE_ENTRY_SIZE 2 > +#define XDMA_AST2600_HOST_CMDQ_ADDR0 0x00 > +#define XDMA_AST2600_HOST_CMDQ_ADDR1 0x04 > +#define XDMA_AST2600_HOST_CMDQ_ENDP 0x08 > +#define XDMA_AST2600_HOST_CMDQ_WRITEP 0x0c > +#define XDMA_AST2600_HOST_CMDQ_READP 0x10 > +#define XDMA_AST2600_BMC_CMDQ_ADDR 0x14 > +#define XDMA_AST2600_BMC_CMDQ_ENDP 0x18 > +#define XDMA_AST2600_BMC_CMDQ_WRITEP 0x1c > +#define XDMA_AST2600_BMC_CMDQ_READP 0x20 > +#define XDMA_AST2600_VGA_CMDQ_ADDR0 0x24 > +#define XDMA_AST2600_VGA_CMDQ_ADDR1 0x28 > +#define XDMA_AST2600_VGA_CMDQ_ENDP 0x2c > +#define XDMA_AST2600_VGA_CMDQ_WRITEP 0x30 > +#define XDMA_AST2600_VGA_CMDQ_READP 0x34 > +#define XDMA_AST2600_CTRL 0x38 > +#define XDMA_AST2600_CTRL_US_COMP BIT(16) > +#define XDMA_AST2600_CTRL_DS_COMP BIT(17) > +#define XDMA_AST2600_CTRL_DS_DIRTY BIT(18) > +#define XDMA_AST2600_CTRL_DS_SIZE_256 BIT(20) > +#define XDMA_AST2600_STATUS 0x3c > +#define XDMA_AST2600_STATUS_US_COMP BIT(16) > +#define XDMA_AST2600_STATUS_DS_COMP BIT(17) > +#define XDMA_AST2600_STATUS_DS_DIRTY BIT(18) > +#define XDMA_AST2600_INPRG_DS_CMD00 0x40 > +#define XDMA_AST2600_INPRG_DS_CMD01 0x44 > +#define XDMA_AST2600_INPRG_DS_CMD10 0x48 > +#define XDMA_AST2600_INPRG_DS_CMD11 0x4c > +#define XDMA_AST2600_INPRG_DS_CMD20 0x50 > +#define XDMA_AST2600_INPRG_DS_CMD21 0x54 > +#define XDMA_AST2600_INPRG_US_CMD00 0x60 > +#define XDMA_AST2600_INPRG_US_CMD01 0x64 > +#define XDMA_AST2600_INPRG_US_CMD10 0x68 > +#define XDMA_AST2600_INPRG_US_CMD11 0x6c > +#define XDMA_AST2600_INPRG_US_CMD20 0x70 > +#define XDMA_AST2600_INPRG_US_CMD21 0x74 > + > +struct aspeed_xdma_cmd { > + u64 host_addr; > + u64 pitch; > + u64 cmd; > + u64 reserved; > +}; > + > +struct aspeed_xdma_regs { > + u8 bmc_cmdq_addr; > + u8 bmc_cmdq_endp; > + u8 bmc_cmdq_writep; > + u8 bmc_cmdq_readp; > + u8 control; > + u8 status; > +}; > + > +struct aspeed_xdma_status_bits { > + u32 us_comp; > + u32 ds_comp; > + u32 ds_dirty; > +}; > + > +struct aspeed_xdma; > + > +struct aspeed_xdma_chip { > + u32 control; > + u32 scu_bmc_class; > + u32 scu_misc_ctrl; > + u32 scu_pcie_conf; > + unsigned int queue_entry_size; > + struct aspeed_xdma_regs regs; > + struct aspeed_xdma_status_bits status_bits; > + unsigned int (*set_cmd)(struct aspeed_xdma *ctx, > + struct aspeed_xdma_cmd cmds[2], > + struct aspeed_xdma_op *op, u32 bmc_addr); > +}; > + > +struct aspeed_xdma_client; > + > +struct aspeed_xdma { > + const struct aspeed_xdma_chip *chip; > + > + struct device *dev; > + void __iomem *base; > + struct clk *clock; > + struct reset_control *reset; > + struct reset_control *reset_rc; > + > + /* Protects current_client */ > + spinlock_t client_lock; > + struct aspeed_xdma_client *current_client; > + > + /* Protects engine configuration */ > + spinlock_t engine_lock; > + struct aspeed_xdma_cmd *cmdq; > + unsigned int cmd_idx; > + bool in_reset; > + bool upstream; > + > + /* Queue waiters for idle engine */ > + wait_queue_head_t wait; > + > + struct work_struct reset_work; > + > + u32 mem_phys; > + u32 mem_size; > + void __iomem *mem_virt; > + dma_addr_t cmdq_phys; > + struct gen_pool *pool; > +}; > + > +struct aspeed_xdma_client { > + struct aspeed_xdma *ctx; > + > + bool error; > + bool in_progress; > + void *virt; > + dma_addr_t phys; > + u32 size; > +}; > + > +static u32 aspeed_xdma_readl(struct aspeed_xdma *ctx, u8 reg) > +{ > + u32 v = readl(ctx->base + reg); > + > + dev_dbg(ctx->dev, "read %02x[%08x]\n", reg, v); > + return v; > +} > + > +static void aspeed_xdma_writel(struct aspeed_xdma *ctx, u8 reg, u32 val) > +{ > + writel(val, ctx->base + reg); > + dev_dbg(ctx->dev, "write %02x[%08x]\n", reg, val); > +} > + > +static void aspeed_xdma_init_eng(struct aspeed_xdma *ctx) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&ctx->engine_lock, flags); > + aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_endp, > + ctx->chip->queue_entry_size * XDMA_NUM_CMDS); > + aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_readp, > + XDMA_BMC_CMDQ_READP_RESET); > + aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, 0); > + aspeed_xdma_writel(ctx, ctx->chip->regs.control, ctx->chip->control); > + aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_addr, ctx->cmdq_phys); > + > + ctx->cmd_idx = 0; > + spin_unlock_irqrestore(&ctx->engine_lock, flags); > +} > + > +static unsigned int aspeed_xdma_ast2500_set_cmd(struct aspeed_xdma *ctx, > + struct aspeed_xdma_cmd cmds[2], > + struct aspeed_xdma_op *op, > + u32 bmc_addr) > +{ > + unsigned int rc = 1; > + unsigned int pitch = 1; > + unsigned int line_no = 1; > + unsigned int line_size = op->len >> > + XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT; > + u64 cmd = XDMA_CMD_AST2500_CMD_IRQ_EN | XDMA_CMD_AST2500_CMD_IRQ_BMC | > + XDMA_CMD_AST2500_CMD_ID; > + u64 cmd_pitch = (op->direction ? XDMA_CMD_AST2500_PITCH_UPSTREAM : 0) | > + XDMA_CMD_AST2500_PITCH_ID; > + > + dev_dbg(ctx->dev, "xdma %s ast2500: bmc[%08x] len[%08x] host[%08x]\n", > + op->direction ? "upstream" : "downstream", bmc_addr, op->len, > + (u32)op->host_addr); > + > + if (op->len > XDMA_CMD_AST2500_CMD_LINE_SIZE) { > + unsigned int rem; > + unsigned int total; > + > + line_no = op->len / XDMA_CMD_AST2500_CMD_LINE_SIZE; > + total = XDMA_CMD_AST2500_CMD_LINE_SIZE * line_no; > + rem = (op->len - total) >> > + XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT; > + line_size = XDMA_CMD_AST2500_CMD_LINE_SIZE; > + pitch = line_size >> XDMA_CMD_AST2500_PITCH_SHIFT; > + line_size >>= XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT; > + > + if (rem) { > + u32 rbmc = bmc_addr + total; > + > + cmds[1].host_addr = op->host_addr + (u64)total; > + cmds[1].pitch = cmd_pitch | > + ((u64)rbmc & XDMA_CMD_AST2500_PITCH_ADDR) | > + FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, 1) | > + FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, 1); > + cmds[1].cmd = cmd | > + FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, 1) | > + FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, > + rem); > + cmds[1].reserved = 0ULL; > + > + print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET, > + 16, 1, &cmds[1], sizeof(*cmds), > + true); > + > + cmd &= ~(XDMA_CMD_AST2500_CMD_IRQ_EN | > + XDMA_CMD_AST2500_CMD_IRQ_BMC); > + > + rc++; > + } > + } > + > + cmds[0].host_addr = op->host_addr; > + cmds[0].pitch = cmd_pitch | > + ((u64)bmc_addr & XDMA_CMD_AST2500_PITCH_ADDR) | > + FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, pitch) | > + FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, pitch); > + cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, line_no) | > + FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, line_size); > + cmds[0].reserved = 0ULL; > + > + print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds, > + sizeof(*cmds), true); > + > + return rc; > +} > + > +static unsigned int aspeed_xdma_ast2600_set_cmd(struct aspeed_xdma *ctx, > + struct aspeed_xdma_cmd cmds[2], > + struct aspeed_xdma_op *op, > + u32 bmc_addr) > +{ > + unsigned int rc = 1; > + unsigned int pitch = 1; > + unsigned int line_no = 1; > + unsigned int line_size = op->len; > + u64 cmd = XDMA_CMD_AST2600_CMD_IRQ_BMC | > + (op->direction ? XDMA_CMD_AST2600_CMD_UPSTREAM : 0); > + > + if (op->host_addr & 0xffffffff00000000ULL || > + (op->host_addr + (u64)op->len) & 0xffffffff00000000ULL) > + cmd |= XDMA_CMD_AST2600_CMD_64_EN; > + > + dev_dbg(ctx->dev, "xdma %s ast2600: bmc[%08x] len[%08x] " > + "host[%016llx]\n", op->direction ? "upstream" : "downstream", > + bmc_addr, op->len, op->host_addr); > + > + if (op->len > XDMA_CMD_AST2600_CMD_LINE_SIZE) { > + unsigned int rem; > + unsigned int total; > + > + line_no = op->len / XDMA_CMD_AST2600_CMD_MULTILINE_SIZE; > + total = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE * line_no; > + rem = op->len - total; > + line_size = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE; > + pitch = line_size; > + > + if (rem) { > + u32 rbmc = bmc_addr + total; > + > + cmds[1].host_addr = op->host_addr + (u64)total; > + cmds[1].pitch = > + ((u64)rbmc & XDMA_CMD_AST2600_PITCH_ADDR) | > + FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, 1) | > + FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, 1); > + cmds[1].cmd = cmd | > + FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, 1) | > + FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, > + rem); > + cmds[1].reserved = 0ULL; > + > + print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET, > + 16, 1, &cmds[1], sizeof(*cmds), > + true); > + > + cmd &= ~XDMA_CMD_AST2600_CMD_IRQ_BMC; > + > + rc++; > + } > + } > + > + cmds[0].host_addr = op->host_addr; > + cmds[0].pitch = ((u64)bmc_addr & XDMA_CMD_AST2600_PITCH_ADDR) | > + FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, pitch) | > + FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, pitch); > + cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, line_no) | > + FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, line_size); > + cmds[0].reserved = 0ULL; > + > + print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds, > + sizeof(*cmds), true); > + > + return rc; > +} > + > +static int aspeed_xdma_start(struct aspeed_xdma *ctx, unsigned int num_cmds, > + struct aspeed_xdma_cmd cmds[2], bool upstream, > + struct aspeed_xdma_client *client) > +{ > + unsigned int i; > + int rc = -EBUSY; > + unsigned long flags; > + > + spin_lock_irqsave(&ctx->engine_lock, flags); > + if (ctx->in_reset) > + goto unlock; > + > + spin_lock(&ctx->client_lock); > + if (ctx->current_client) { > + spin_unlock(&ctx->client_lock); > + goto unlock; > + } > + > + client->error = false; > + client->in_progress = true; > + ctx->current_client = client; > + spin_unlock(&ctx->client_lock); > + > + for (i = 0; i < num_cmds; ++i) { > + memcpy(&ctx->cmdq[ctx->cmd_idx], &cmds[i], > + sizeof(struct aspeed_xdma_cmd)); > + ctx->cmd_idx = (ctx->cmd_idx + 1) % XDMA_NUM_CMDS; > + } > + ctx->upstream = upstream; > + aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, > + ctx->cmd_idx * ctx->chip->queue_entry_size); > + rc = 0; > + > +unlock: > + spin_unlock_irqrestore(&ctx->engine_lock, flags); > + return rc; > +} > + > +static void aspeed_xdma_done(struct aspeed_xdma *ctx, bool error) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&ctx->client_lock, flags); > + if (ctx->current_client) { > + ctx->current_client->error = error; > + ctx->current_client->in_progress = false; > + ctx->current_client = NULL; > + } > + spin_unlock_irqrestore(&ctx->client_lock, flags); > + > + wake_up_interruptible_all(&ctx->wait); > +} > + > +static irqreturn_t aspeed_xdma_irq(int irq, void *arg) > +{ > + struct aspeed_xdma *ctx = arg; > + u32 status; > + > + spin_lock(&ctx->engine_lock); > + status = aspeed_xdma_readl(ctx, ctx->chip->regs.status); > + > + if (status & ctx->chip->status_bits.ds_dirty) { > + aspeed_xdma_done(ctx, true); > + } else { > + if (status & ctx->chip->status_bits.us_comp) { > + if (ctx->upstream) > + aspeed_xdma_done(ctx, false); > + } > + > + if (status & ctx->chip->status_bits.ds_comp) { > + if (!ctx->upstream) > + aspeed_xdma_done(ctx, false); > + } > + } > + > + aspeed_xdma_writel(ctx, ctx->chip->regs.status, status); > + spin_unlock(&ctx->engine_lock); > + > + return IRQ_HANDLED; > +} > + > +static void aspeed_xdma_reset(struct aspeed_xdma *ctx) > +{ > + unsigned long flags; > + > + reset_control_assert(ctx->reset); > + usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US, > + XDMA_ENGINE_SETUP_TIME_MAX_US); > + reset_control_deassert(ctx->reset); > + usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US, > + XDMA_ENGINE_SETUP_TIME_MAX_US); > + > + aspeed_xdma_init_eng(ctx); > + > + aspeed_xdma_done(ctx, true); > + > + spin_lock_irqsave(&ctx->engine_lock, flags); > + ctx->in_reset = false; > + spin_unlock_irqrestore(&ctx->engine_lock, flags); > + > + wake_up_interruptible(&ctx->wait); > +} > + > +static void aspeed_xdma_reset_work(struct work_struct *work) > +{ > + struct aspeed_xdma *ctx = container_of(work, struct aspeed_xdma, > + reset_work); > + > + aspeed_xdma_reset(ctx); > +} > + > +static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg) > +{ > + struct aspeed_xdma *ctx = arg; > + > + dev_dbg(ctx->dev, "PCI-E reset requested.\n"); > + > + spin_lock(&ctx->engine_lock); > + if (ctx->in_reset) { > + spin_unlock(&ctx->engine_lock); > + return IRQ_HANDLED; > + } > + > + ctx->in_reset = true; > + spin_unlock(&ctx->engine_lock); > + > + schedule_work(&ctx->reset_work); > + return IRQ_HANDLED; > +} > + > +static int aspeed_xdma_init_scu(struct aspeed_xdma *ctx, struct device *dev) > +{ > + struct regmap *scu = syscon_regmap_lookup_by_phandle(dev->of_node, > + "aspeed,scu"); > + > + if (!IS_ERR(scu)) { > + u32 selection; > + bool pcie_device_bmc = true; > + const u32 bmc = SCU_PCIE_CONF_BMC_EN | > + SCU_PCIE_CONF_BMC_EN_MSI | SCU_PCIE_CONF_BMC_EN_IRQ | > + SCU_PCIE_CONF_BMC_EN_DMA; > + const u32 vga = SCU_PCIE_CONF_VGA_EN | > + SCU_PCIE_CONF_VGA_EN_MSI | SCU_PCIE_CONF_VGA_EN_IRQ | > + SCU_PCIE_CONF_VGA_EN_DMA; > + const char *pcie = NULL; > + > + if (!of_property_read_string(dev->of_node, "pcie-device", > + &pcie)) { > + if (!strcmp(pcie, "vga")) { > + pcie_device_bmc = false; > + } else if (strcmp(pcie, "bmc")) { > + dev_err(dev, > + "Invalid pcie-device property %s.\n", > + pcie); > + return -EINVAL; > + } > + } > + > + if (pcie_device_bmc) { > + selection = bmc; > + regmap_write(scu, ctx->chip->scu_bmc_class, > + SCU_BMC_CLASS_REV_XDMA); > + } else { > + selection = vga; > + } > + > + regmap_update_bits(scu, ctx->chip->scu_pcie_conf, bmc | vga, > + selection); > + > + if (ctx->chip->scu_misc_ctrl) > + regmap_update_bits(scu, ctx->chip->scu_misc_ctrl, > + SCU_AST2600_MISC_CTRL_XDMA_BMC, > + SCU_AST2600_MISC_CTRL_XDMA_BMC); > + } else { > + dev_warn(dev, "Unable to configure PCIe: %ld; continuing.\n", > + PTR_ERR(scu)); > + } > + > + return 0; > +} > + > +static int aspeed_xdma_probe(struct platform_device *pdev) > +{ > + int rc; > + int irq; > + int pcie_irq; > + struct aspeed_xdma *ctx; > + struct reserved_mem *mem; > + struct device *dev = &pdev->dev; > + struct device_node *memory_region; > + const void *md = of_device_get_match_data(dev); > + > + if (!md) > + return -ENODEV; > + > + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); > + if (!ctx) > + return -ENOMEM; > + > + ctx->chip = md; > + ctx->dev = dev; > + platform_set_drvdata(pdev, ctx); > + spin_lock_init(&ctx->client_lock); > + spin_lock_init(&ctx->engine_lock); > + INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work); > + init_waitqueue_head(&ctx->wait); > + > + ctx->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(ctx->base)) { > + dev_err(dev, "Failed to map registers.\n"); > + return PTR_ERR(ctx->base); > + } > + > + irq = platform_get_irq(pdev, 0); > + if (irq < 0) { > + dev_err(dev, "Failed to find IRQ.\n"); > + return irq; > + } > + > + rc = devm_request_irq(dev, irq, aspeed_xdma_irq, 0, DEVICE_NAME, ctx); > + if (rc < 0) { > + dev_err(dev, "Failed to request IRQ %d.\n", irq); > + return rc; > + } > + > + ctx->clock = devm_clk_get(dev, NULL); > + if (IS_ERR(ctx->clock)) { > + dev_err(dev, "Failed to request clock.\n"); > + return PTR_ERR(ctx->clock); > + } > + > + ctx->reset = devm_reset_control_get_exclusive(dev, NULL); > + if (IS_ERR(ctx->reset)) { > + dev_err(dev, "Failed to request reset control.\n"); > + return PTR_ERR(ctx->reset); > + } > + > + ctx->reset_rc = devm_reset_control_get_exclusive(dev, "rc"); > + if (IS_ERR(ctx->reset_rc)) { > + dev_dbg(dev, "Failed to request reset RC control.\n"); > + ctx->reset_rc = NULL; > + } > + > + ctx->pool = devm_gen_pool_create(dev, ilog2(PAGE_SIZE), -1, NULL); > + if (!ctx->pool) { > + dev_err(dev, "Failed to setup genalloc pool.\n"); > + return -ENOMEM; > + } > + > + memory_region = of_parse_phandle(dev->of_node, "memory-region", 0); > + if (!memory_region) { > + dev_err(dev, "Failed to find memory-region.\n"); > + return -ENOMEM; > + } > + > + mem = of_reserved_mem_lookup(memory_region); > + of_node_put(memory_region); > + if (!mem) { > + dev_err(dev, "Failed to find reserved memory.\n"); > + return -ENOMEM; > + } > + > + ctx->mem_phys = mem->base; > + ctx->mem_size = mem->size; > + > + ctx->mem_virt = devm_ioremap(dev, ctx->mem_phys, ctx->mem_size); This isn't _really_ the right thing to do and there were complaints that it was causing issues under qemu wrt MT_DEVICE. I'll do some experiments with the DMA API. Andrew