This patch implements the APM X-Gene SoC DMA engine driver. The APM X-Gene SoC DMA engine consists of 4 DMA channels for performing DMA operations. These DMA operations include memory copy and scatter-gather memory copy offloading. Signed-off-by: Rameshwar Prasad Sahu <rsahu@xxxxxxx> Signed-off-by: Loc Ho <lho@xxxxxxx> --- drivers/dma/Kconfig | 8 + drivers/dma/Makefile | 1 + drivers/dma/xgene-dma.c | 1738 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1747 insertions(+) create mode 100755 drivers/dma/xgene-dma.c diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index a874b6e..0e05831 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -425,6 +425,14 @@ config IMG_MDC_DMA help Enable support for the IMG multi-threaded DMA controller (MDC). +config XGENE_DMA + tristate "APM X-Gene DMA support" + depends on ARCH_XGENE + select DMA_ENGINE + select ASYNC_TX_ENABLE_CHANNEL_SWITCH + help + Enable support for the APM X-Gene SoC DMA engine. + config DMA_ENGINE bool diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index f915f61..06c1576 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -51,3 +51,4 @@ obj-$(CONFIG_INTEL_MIC_X100_DMA) += mic_x100_dma.o obj-$(CONFIG_NBPFAXI_DMA) += nbpfaxi.o obj-$(CONFIG_DMA_SUN6I) += sun6i-dma.o obj-$(CONFIG_IMG_MDC_DMA) += img-mdc-dma.o +obj-$(CONFIG_XGENE_DMA) += xgene-dma.o diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c new file mode 100755 index 0000000..e736c2e --- /dev/null +++ b/drivers/dma/xgene-dma.c @@ -0,0 +1,1738 @@ +/* + * Applied Micro X-Gene SoC DMA engine Driver + * + * Copyright (c) 2015, Applied Micro Circuits Corporation + * Authors: Rameshwar Prasad Sahu <rsahu@xxxxxxx> + * Loc Ho <lho@xxxxxxx> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * NOTE: PM support is currently not available. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/dmapool.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> + +#include "dmaengine.h" + +/* DMA ring csr registers and bit definations */ +#define DMA_RING_CONFIG 0x04 +#define DMA_RING_ENABLE BIT(31) +#define DMA_RING_ID 0x08 +#define DMA_RING_ID_SETUP(v) ((v) | BIT(31)) +#define DMA_RING_ID_BUF 0x0C +#define DMA_RING_ID_BUF_SETUP(v) (((v) << 9) | BIT(21)) +#define DMA_RING_THRESLD0_SET1 0x30 +#define DMA_RING_THRESLD0_SET1_VAL 0X64 +#define DMA_RING_THRESLD1_SET1 0x34 +#define DMA_RING_THRESLD1_SET1_VAL 0xC8 +#define DMA_RING_HYSTERESIS 0x68 +#define DMA_RING_HYSTERESIS_VAL 0xFFFFFFFF +#define DMA_RING_STATE 0x6C +#define DMA_RING_STATE_WR_BASE 0x70 +#define DMA_RING_NE_INT_MODE 0x017C +#define DMA_RING_NE_INT_MODE_SET(m, v) \ + ((m) = ((m) & ~BIT(31 - (v))) | BIT(31 - (v))) +#define DMA_RING_NE_INT_MODE_RESET(m, v) \ + ((m) &= (~BIT(31 - (v)))) +#define DMA_RING_CLKEN 0xC208 +#define DMA_RING_SRST 0xC200 +#define DMA_RING_MEM_RAM_SHUTDOWN 0xD070 +#define DMA_RING_BLK_MEM_RDY 0xD074 +#define DMA_RING_BLK_MEM_RDY_VAL 0xFFFFFFFF +#define DMA_RING_DESC_CNT(v) (((v) & 0x0001FFFE) >> 1) +#define DMA_RING_ID_GET(owner, num) (((owner) << 6) | (num)) +#define DMA_RING_DST_ID(v) ((1 << 10) | (v)) +#define DMA_RING_CMD_OFFSET 0x2C +#define DMA_RING_CMD_BASE_OFFSET(v) ((v) << 6) +#define DMA_RING_COHERENT_SET(m) (((u32 *)(m))[2] |= BIT(4)) +#define DMA_RING_ADDRL_SET(m, v) (((u32 *)(m))[2] |= (((v) >> 8) << 5)) +#define DMA_RING_ADDRH_SET(m, v) (((u32 *)(m))[3] |= ((v) >> 35)) +#define DMA_RING_ACCEPTLERR_SET(m) (((u32 *)(m))[3] |= BIT(19)) +#define DMA_RING_SIZE_SET(m, v) (((u32 *)(m))[3] |= ((v) << 23)) +#define DMA_RING_RECOMBBUF_SET(m) (((u32 *)(m))[3] |= BIT(27)) +#define DMA_RING_RECOMTIMEOUTL_SET(m) (((u32 *)(m))[3] |= (0x7 << 28)) +#define DMA_RING_RECOMTIMEOUTH_SET(m) (((u32 *)(m))[4] |= 0x3) +#define DMA_RING_SELTHRSH_SET(m) (((u32 *)(m))[4] |= BIT(3)) +#define DMA_RING_TYPE_SET(m, v) (((u32 *)(m))[4] |= ((v) << 19)) + +/* DMA device csr registers and bit definitions */ +#define DMA_IPBRR 0x0 +#define DMA_DEV_ID_RD(v) ((v) & 0x00000FFF) +#define DMA_BUS_ID_RD(v) (((v) >> 12) & 3) +#define DMA_REV_NO_RD(v) (((v) >> 14) & 3) +#define DMA_GCR 0x10 +#define DMA_CH_SETUP(v) ((v) = ((v) & ~0x000FFFFF) | 0x000AAFFF) +#define DMA_ENABLE(v) ((v) |= BIT(31)) +#define DMA_DISABLE(v) ((v) &= ~BIT(31)) +#define DMA_INT 0x70 +#define DMA_INT_MASK 0x74 +#define DMA_INT_ALL_MASK 0xFFFFFFFF +#define DMA_INT_ALL_UNMASK 0x0 +#define DMA_INT_MASK_SHIFT 0x14 +#define DMA_RING_INT0_MASK 0x90A0 +#define DMA_RING_INT1_MASK 0x90A8 +#define DMA_RING_INT2_MASK 0x90B0 +#define DMA_RING_INT3_MASK 0x90B8 +#define DMA_RING_INT4_MASK 0x90C0 +#define DMA_CFG_RING_WQ_ASSOC 0x90E0 +#define DMA_ASSOC_RING_MNGR1 0xFFFFFFFF +#define DMA_MEM_RAM_SHUTDOWN 0xD070 +#define DMA_BLK_MEM_RDY 0xD074 +#define DMA_BLK_MEM_RDY_VAL 0xFFFFFFFF + +/* DMA Descriptor format */ +#define DMA_DESC_ELERR_RD(m) (((m) >> 46) & 0x3) +#define DMA_DESC_NV_SET(m) (((u64 *)(m))[0] |= BIT_ULL(50)) +#define DMA_DESC_IN_SET(m) (((u64 *)(m))[0] |= BIT_ULL(55)) +#define DMA_DESC_RTYPE_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 56)) +#define DMA_DESC_LERR_RD(m) (((m) >> 60) & 0x7) +#define DMA_DESC_BUFADDR_SET(m, v) (((u64 *)(m))[0] |= (v)) +#define DMA_DESC_BUFLEN_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 48)) +#define DMA_DESC_C_SET(m) (((u64 *)(m))[1] |= BIT_ULL(63)) +#define DMA_DESC_DR_SET(m) (((u64 *)(m))[2] |= BIT_ULL(61)) +#define DMA_DESC_DST_ADDR_SET(m, v) (((u64 *)(m))[3] |= (v)) +#define DMA_DESC_H0ENQ_NUM_SET(m, v) (((u64 *)(m))[3] |= ((u64)(v) << 48)) +#define DMA_DESC_STATUS(x, y) (((x) << 4) | (y)) + +/* DMA descriptor empty s/w signature */ +#define DMA_DESC_EMPTY_INDEX 0 +#define DMA_DESC_EMPTY_SIGNATURE ~0ULL +#define DMA_DESC_SET_EMPTY(m) \ + (((u64 *)(m))[DMA_DESC_EMPTY_INDEX] = DMA_DESC_EMPTY_SIGNATURE) +#define DMA_DESC_IS_EMPTY(m) \ + (((u64 *)(m))[DMA_DESC_EMPTY_INDEX] == DMA_DESC_EMPTY_SIGNATURE) + +/* DMA configurable parameters defines */ +#define DMA_RING_NUM 512 +#define DMA_BUFNUM 0x0 +#define DMA_CPU_BUFNUM 0x18 +#define DMA_RING_OWNER_DMA 0x03 +#define DMA_RING_OWNER_CPU 0x0F +#define DMA_RING_TYPE_REGULAR 0x01 +#define DMA_RING_WQ_DESC_SIZE 32 +#define DMA_RING_NUM_CONFIG 5 +#define DMA_MAX_CHANNEL 4 +#define DMA_MAX_BYTE_CNT 0x4000 /* 16 KB */ +#define DMA_MAX_64B_DESC_BYTE_CNT 0x14000 /* 80 KB */ +#define DMA_16K_BUFFER_LEN_CODE 0x0 +#define DMA_INVALID_LEN_CODE 0x7800 + +/* DMA descriptor error codes */ +#define ERR_DESC_AXI 0x01 +#define ERR_BAD_DESC 0x02 +#define ERR_READ_DATA_AXI 0x03 +#define ERR_WRITE_DATA_AXI 0x04 +#define ERR_FBP_TIMEOUT 0x05 +#define ERR_ECC 0x06 +#define ERR_DIFF_SIZE 0x08 +#define ERR_SCT_GAT_LEN 0x09 +#define ERR_CRC_ERR 0x11 +#define ERR_CHKSUM 0x12 +#define ERR_DIF 0x13 + +/* DMA error interrupt codes */ +#define ERR_DIF_SIZE_INT 0x0 +#define ERR_GS_ERR_INT 0x1 +#define ERR_FPB_TIMEO_INT 0x2 +#define ERR_WFIFO_OVF_INT 0x3 +#define ERR_RFIFO_OVF_INT 0x4 +#define ERR_WR_TIMEO_INT 0x5 +#define ERR_RD_TIMEO_INT 0x6 +#define ERR_WR_ERR_INT 0x7 +#define ERR_RD_ERR_INT 0x8 +#define ERR_BAD_DESC_INT 0x9 +#define ERR_DESC_DST_INT 0xA +#define ERR_DESC_SRC_INT 0xB + +/* Define to dump DMA descriptor */ +#define DMA_DESC_ERR_DUMP(desc) \ + print_hex_dump(KERN_ERR, "X-Gene DMA: Rx ERR DESC ", \ + DUMP_PREFIX_ADDRESS, 16, 8, (desc), 32, 0) + +#define to_dma_desc_sw(tx) \ + container_of(tx, struct xgene_dma_desc_sw, tx) +#define to_dma_chan(dchan) \ + container_of(dchan, struct xgene_dma_chan, dma_chan) + +#define chan_dbg(chan, fmt, arg...) \ + dev_dbg(chan->dev, "%s: " fmt, chan->name, ##arg) +#define chan_err(chan, fmt, arg...) \ + dev_err(chan->dev, "%s: " fmt, chan->name, ##arg) + +struct xgene_dma_desc_hw { + u64 m0; + u64 m1; + u64 m2; + u64 m3; +}; + +enum xgene_dma_ring_cfgsize { + DMA_RING_CFG_SIZE_512B, + DMA_RING_CFG_SIZE_2KB, + DMA_RING_CFG_SIZE_16KB, + DMA_RING_CFG_SIZE_64KB, + DMA_RING_CFG_SIZE_512KB, + DMA_RING_CFG_SIZE_INVALID +}; + +struct xgene_dma_ring { + struct xgene_dma *pdma; + u8 buf_num; + u16 id; + u16 num; + u16 head; + u16 owner; + u16 slots; + u16 dst_ring_num; + u32 size; + void __iomem *cmd; + void __iomem *cmd_base; + dma_addr_t desc_paddr; + u32 state[DMA_RING_NUM_CONFIG]; + enum xgene_dma_ring_cfgsize cfgsize; + union { + void *desc_vaddr; + struct xgene_dma_desc_hw *desc_hw; + }; +}; + +struct xgene_dma_desc_sw { + struct xgene_dma_desc_hw desc1; + struct xgene_dma_desc_hw desc2; + u8 desc_cnt; + struct list_head node; + struct list_head tx_list; + struct dma_async_tx_descriptor tx; +}; + +/** + * struct xgene_dma_chan - internal representation of an DMA channel + * @dma_chan: dmaengine channel object member + * @pdma: DMA device structure reference + * @dev: struct device reference for dma mapping api + * @id: raw id of this channel + * @rx_irq: channel IRQ + * @name: name of DMA channel + * @lock: serializes enqueue/dequeue operations to the descriptor pool + * @pending: number of transaction request pushed to DMA controller for + * execution, but still waiting for completion, + * @ld_pending: descriptors which are queued to run, but have not yet been + * submitted to the hardware for execution + * @ld_running: descriptors which are currently being executing by the hardware + * @ld_completed: descriptors which have finished execution by the hardware. + * These descriptors have already had their cleanup actions run. They + * are waiting for the ACK bit to be set by the async tx API. + * @desc_pool: descriptor pool for DMA operations + * @tasklet: bottom half where all completed descriptors cleans + * @tx_ring: transmit ring descriptor that we use to prepare actual + * descriptors for further executions + * @rx_ring: receive ring descriptor that we use to get completed DMA + * descriptors during cleanup time + */ +struct xgene_dma_chan { + struct dma_chan dma_chan; + struct xgene_dma *pdma; + struct device *dev; + int id; + int rx_irq; + char name[8]; + spinlock_t lock; + int pending; + struct list_head ld_pending; + struct list_head ld_running; + struct list_head ld_completed; + struct dma_pool *desc_pool; + struct tasklet_struct tasklet; + struct xgene_dma_ring tx_ring; + struct xgene_dma_ring rx_ring; +}; + +/** + * struct xgene_dma - internal representation of an DMA device + * @err_irq: DMA error irq number + * @ring_num: start id number for DMA ring + * @csr_dma: base for DMA register access + * @csr_ring: base for DMA ring register access + * @csr_ring_cmd: base for DMA ring command register access + * @dma_dev: embedded struct dma_device + * @chan: reference to DMA channels + */ +struct xgene_dma { + struct device *dev; + struct clk *clk; + int err_irq; + int ring_num; + void __iomem *csr_dma; + void __iomem *csr_ring; + void __iomem *csr_ring_cmd; + struct dma_device dma_dev[DMA_MAX_CHANNEL]; + struct xgene_dma_chan chan[DMA_MAX_CHANNEL]; +}; + +static const char * const xgene_dma_desc_hw_err[] = { + [ERR_DESC_AXI] = "AXI error when reading src/dst link list", + [ERR_BAD_DESC] = "ERR or El_ERR fields not set to zero in desc", + [ERR_READ_DATA_AXI] = "AXI error when reading data", + [ERR_WRITE_DATA_AXI] = "AXI error when writing data", + [ERR_FBP_TIMEOUT] = "Timeout on bufpool fetch", + [ERR_ECC] = "ECC double bit error", + [ERR_DIFF_SIZE] = "Bufpool too small to hold all the DIF result", + [ERR_SCT_GAT_LEN] = "Gather and scatter data length not same", + [ERR_CRC_ERR] = "CRC error", + [ERR_CHKSUM] = "Checksum error", + [ERR_DIF] = "DIF error", +}; + +static const char * const xgene_dma_err[] = { + [ERR_DIF_SIZE_INT] = "DIF size error", + [ERR_GS_ERR_INT] = "Gather scatter not same size error", + [ERR_FPB_TIMEO_INT] = "Free pool time out error", + [ERR_WFIFO_OVF_INT] = "Write FIFO over flow error", + [ERR_RFIFO_OVF_INT] = "Read FIFO over flow error", + [ERR_WR_TIMEO_INT] = "Write time out error", + [ERR_RD_TIMEO_INT] = "Read time out error", + [ERR_WR_ERR_INT] = "HBF bus write error", + [ERR_RD_ERR_INT] = "HBF bus read error", + [ERR_BAD_DESC_INT] = "Ring descriptor HE0 not set error", + [ERR_DESC_DST_INT] = "HFB reading dst link address error", + [ERR_DESC_SRC_INT] = "HFB reading src link address error", +}; + +static void xgene_dma_cpu_to_le64(u64 *desc, int count) +{ + int i; + + for (i = 0; i < count; i++) + desc[i] = cpu_to_le64(desc[i]); +} + +static u16 xgene_dma_encode_len(u32 len) +{ + return (len < DMA_MAX_BYTE_CNT) ? + len : DMA_16K_BUFFER_LEN_CODE; +} + +static u32 xgene_dma_ring_desc_cnt(struct xgene_dma_ring *ring) +{ + u32 __iomem *cmd_base = ring->cmd_base; + u32 ring_state = ioread32(&cmd_base[1]); + + return DMA_RING_DESC_CNT(ring_state); +} + +static void xgene_dma_set_src_buffer(void *ext8, size_t *len, + dma_addr_t *paddr) +{ + size_t nbytes = (*len < DMA_MAX_BYTE_CNT) ? + *len : DMA_MAX_BYTE_CNT; + + DMA_DESC_BUFADDR_SET(ext8, *paddr); + DMA_DESC_BUFLEN_SET(ext8, xgene_dma_encode_len(*len)); + *len -= nbytes; + *paddr += nbytes; +} + +static void xgene_dma_invalidate_buffer(void *ext8) +{ + DMA_DESC_BUFLEN_SET(ext8, DMA_INVALID_LEN_CODE); +} + +static void *xgene_dma_lookup_ext8(u64 *desc, int idx) +{ + return (idx % 2) ? (desc + idx - 1) : (desc + idx + 1); +} + +static void xgene_dma_init_desc(void *desc, u16 dst_ring_num) +{ + DMA_DESC_C_SET(desc); /* Coherent IO */ + DMA_DESC_IN_SET(desc); + DMA_DESC_DR_SET(desc); + DMA_DESC_RTYPE_SET(desc, DMA_RING_OWNER_DMA); + DMA_DESC_H0ENQ_NUM_SET(desc, dst_ring_num); +} + +static void xgene_dma_prep_cpy_desc(struct xgene_dma_chan *chan, + struct xgene_dma_desc_sw *desc_sw, + dma_addr_t dst, dma_addr_t src, + size_t len) +{ + struct xgene_dma_ring *ring = &chan->tx_ring; + void *desc1, *desc2; + int i; + + /* Get 1st descriptor */ + desc1 = &desc_sw->desc1; + xgene_dma_init_desc(desc1, ring->dst_ring_num); + DMA_DESC_DST_ADDR_SET(desc1, dst); + + /* Set 1st source address */ + xgene_dma_set_src_buffer(desc1 + 8, &len, &src); + + if (len <= 0) { + desc2 = NULL; + desc_sw->desc_cnt = 1; + goto skip_additional_src; + } + + /* + * We need to split this source buffer, + * and need to use 2nd descriptor + */ + desc2 = &desc_sw->desc2; + DMA_DESC_NV_SET(desc1); + + /* Set 2nd to 5th source address */ + for (i = 0; i < 4 && len; i++) + xgene_dma_set_src_buffer(xgene_dma_lookup_ext8(desc2, i), + &len, &src); + + /* Invalidate unused source address field */ + for (; i < 4; i++) + xgene_dma_invalidate_buffer(xgene_dma_lookup_ext8(desc2, i)); + + desc_sw->desc_cnt = 2; + +skip_additional_src: + /* Hardware stores descriptor in little endian format */ + xgene_dma_cpu_to_le64(desc1, 4); + if (desc2) + xgene_dma_cpu_to_le64(desc2, 4); +} + +static dma_cookie_t xgene_dma_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct xgene_dma_desc_sw *desc; + struct xgene_dma_chan *chan; + dma_cookie_t cookie; + + if (unlikely(!tx)) + return -EINVAL; + + chan = to_dma_chan(tx->chan); + desc = to_dma_desc_sw(tx); + + spin_lock_bh(&chan->lock); + + cookie = dma_cookie_assign(tx); + + /* Add this transaction list onto the tail of the pending queue */ + list_splice_tail_init(&desc->tx_list, &chan->ld_pending); + + spin_unlock_bh(&chan->lock); + + return cookie; +} + +static void xgene_dma_free_descriptor(struct xgene_dma_chan *chan, + struct xgene_dma_desc_sw *desc) +{ + list_del(&desc->node); + chan_dbg(chan, "LD %p free\n", desc); + dma_pool_free(chan->desc_pool, desc, desc->tx.phys); +} + +static struct xgene_dma_desc_sw *xgene_dma_alloc_descriptor( + struct xgene_dma_chan *chan) +{ + struct xgene_dma_desc_sw *desc; + dma_addr_t phys; + + desc = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, &phys); + if (!desc) { + chan_dbg(chan, "Failed to allocate LDs\n"); + return NULL; + } + + memset(desc, 0, sizeof(*desc)); + + INIT_LIST_HEAD(&desc->tx_list); + desc->tx.phys = phys; + desc->tx.tx_submit = xgene_dma_tx_submit; + dma_async_tx_descriptor_init(&desc->tx, &chan->dma_chan); + + chan_dbg(chan, "LD %p allocated\n", desc); + + return desc; +} + +/** + * xgene_dma_clean_completed_descriptor - free all descriptors which + * has been completed and acked + * @chan: DMA channel + * + * This function is used on all completed and acked descriptors. + * All descriptors should only be freed in this function. + */ +static void xgene_dma_clean_completed_descriptor(struct xgene_dma_chan *chan) +{ + struct xgene_dma_desc_sw *desc, *_desc; + + /* Run the callback for each descriptor, in order */ + list_for_each_entry_safe(desc, _desc, &chan->ld_completed, node) { + if (async_tx_test_ack(&desc->tx)) + xgene_dma_free_descriptor(chan, desc); + } +} + +/** + * xgene_dma_run_tx_complete_actions - cleanup a single link descriptor + * @chan: DMA channel + * @desc: descriptor to cleanup and free + * + * This function is used on a descriptor which has been executed by the DMA + * controller. It will run any callbacks, submit any dependencies. + */ +static void xgene_dma_run_tx_complete_actions(struct xgene_dma_chan *chan, + struct xgene_dma_desc_sw *desc) +{ + struct dma_async_tx_descriptor *tx = &desc->tx; + + if (tx->cookie == 0) + return; + + dma_cookie_complete(tx); + + /* Run the link descriptor callback function */ + if (tx->callback) + tx->callback(tx->callback_param); + + dma_descriptor_unmap(tx); + + /* Run any dependencies */ + dma_run_dependencies(tx); +} + +/** + * xgene_dma_clean_running_descriptor - move the completed descriptor from + * ld_running to ld_completed + * @chan: DMA channel + * @desc: the descriptor which is completed + * + * Free the descriptor directly if acked by async_tx api, or move it to + * queue ld_completed. + */ +static void xgene_dma_clean_running_descriptor(struct xgene_dma_chan *chan, + struct xgene_dma_desc_sw *desc) +{ + /* Remove from the list of transactions */ + list_del(&desc->node); + + /* + * the client is allowed to attach dependent operations + * until 'ack' is set + */ + if (!async_tx_test_ack(&desc->tx)) { + /* + * Move this descriptor to the list of descriptors which is + * completed, but still awaiting the 'ack' bit to be set. + */ + list_add_tail(&desc->node, &chan->ld_completed); + return; + } + + chan_dbg(chan, "LD %p free\n", desc); + dma_pool_free(chan->desc_pool, desc, desc->tx.phys); +} + +/** + * xgene_chan_xfer_ld_pending - push any pending transactions to hw + * @chan : DMA channel + * + * LOCKING: must hold chan->desc_lock + */ +static void xgene_chan_xfer_ld_pending(struct xgene_dma_chan *chan) +{ + struct xgene_dma_ring *ring = &chan->tx_ring; + struct xgene_dma_desc_sw *desc_sw, *_desc_sw; + struct xgene_dma_desc_hw *desc_hw; + + /* + * If the list of pending descriptors is empty, then we + * don't need to do any work at all + */ + if (list_empty(&chan->ld_pending)) { + chan_dbg(chan, "No pending LDs\n"); + return; + } + + /* + * Move elements from the queue of pending transactions onto the list + * of running transactions and push it to hw for further executions + */ + + list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_pending, node) { + /* + * Check if have pushed max number of transactions to hw + * as capable, so let's stop here and will push remaining + * elements from pening ld queue after completing some + * descriptors that we have already pushed + */ + if ((chan->pending >= ring->slots) || + (xgene_dma_ring_desc_cnt(ring) > (ring->slots - 2))) + break; + + /* Get hw descriptor from DMA tx ring */ + desc_hw = &ring->desc_hw[ring->head]; + + /* + * Increment the head count to point next + * descriptor for next time + */ + if (++ring->head == ring->slots) + ring->head = 0; + + /* Copy prepared sw descriptor data to hw descriptor */ + memcpy(desc_hw, &desc_sw->desc1, sizeof(*desc_hw)); + + /* + * Check if we have prepared 64B descriptor, + * in this case we need one more hw descriptor + */ + if (desc_sw->desc_cnt == 2) { + desc_hw = &ring->desc_hw[ring->head]; + + if (++ring->head == ring->slots) + ring->head = 0; + + memcpy(desc_hw, &desc_sw->desc2, sizeof(*desc_hw)); + } + + /* + * Delete this element from ld pending queue and append it to + * ld running queue + */ + list_move_tail(&desc_sw->node, &chan->ld_running); + + /* Increment the pending transaction count */ + chan->pending++; + + /* Notify the hw that we have descriptor ready for execution */ + iowrite32(desc_sw->desc_cnt, ring->cmd); + } +} + +/** + * xgene_dma_cleanup_descriptors - cleanup link descriptors which are completed + * and move them to ld_completed to free until flag 'ack' is set + * @chan: DMA channel + * + * This function is used on descriptors which have been executed by the DMA + * controller. It will run any callbacks, submit any dependencies, then + * free these descriptors if flag 'ack' is set. + */ +static void xgene_dma_cleanup_descriptors(struct xgene_dma_chan *chan) +{ + struct xgene_dma_ring *ring = &chan->rx_ring; + struct xgene_dma_desc_sw *desc_sw, *_desc_sw; + struct xgene_dma_desc_hw *desc_hw; + u8 status; + + /* Clean already completed and acked descriptors */ + xgene_dma_clean_completed_descriptor(chan); + + /* Run the callback for each descriptor, in order */ + list_for_each_entry_safe(desc_sw, _desc_sw, &chan->ld_running, node) { + /* Get subsequent hw descriptor from DMA rx ring */ + desc_hw = &ring->desc_hw[ring->head]; + + /* Check if this descriptor has been completed */ + if (unlikely(DMA_DESC_IS_EMPTY(desc_hw))) + break; + + if (++ring->head == ring->slots) + ring->head = 0; + + /* Check if we have any error with DMA transactions */ + status = DMA_DESC_STATUS( + DMA_DESC_ELERR_RD(le64_to_cpu(desc_hw->m0)), + DMA_DESC_LERR_RD(le64_to_cpu(desc_hw->m0))); + if (status) { + chan_err(chan, "%s\n", xgene_dma_desc_hw_err[status]); + DMA_DESC_ERR_DUMP(desc_hw); + } + + /* Notify the hw about this completed descriptor */ + iowrite32(-1, ring->cmd); + + /* Mark this hw descriptor as processed */ + DMA_DESC_SET_EMPTY(desc_hw); + + xgene_dma_run_tx_complete_actions(chan, desc_sw); + + xgene_dma_clean_running_descriptor(chan, desc_sw); + + /* + * Decrement the pending transaction count + * as we have processed one + */ + chan->pending--; + } + + /* + * Start any pending transactions automatically + * + * In the ideal case, we keep the DMA controller busy while we go + * ahead and free the descriptors below. + */ + xgene_chan_xfer_ld_pending(chan); +} + +static int xgene_dma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct xgene_dma_chan *chan = to_dma_chan(dchan); + + /* Has this channel already been allocated? */ + if (chan->desc_pool) + return 1; + + chan->desc_pool = dma_pool_create(chan->name, chan->dev, + sizeof(struct xgene_dma_desc_sw), + 0, 0); + if (!chan->desc_pool) { + chan_err(chan, "Failed to allocate descriptor pool\n"); + return -ENOMEM; + } + + chan_dbg(chan, "Allocate descripto pool\n"); + + return 1; +} + +/** + * xgene_dma_free_desc_list - Free all descriptors in a queue + * @chan: DMA channel + * @list: the list to free + * + * LOCKING: must hold chan->desc_lock + */ +static void xgene_dma_free_desc_list(struct xgene_dma_chan *chan, + struct list_head *list) +{ + struct xgene_dma_desc_sw *desc, *_desc; + + list_for_each_entry_safe(desc, _desc, list, node) + xgene_dma_free_descriptor(chan, desc); +} + +static void xgene_dma_free_desc_list_reverse(struct xgene_dma_chan *chan, + struct list_head *list) +{ + struct xgene_dma_desc_sw *desc, *_desc; + + list_for_each_entry_safe_reverse(desc, _desc, list, node) + xgene_dma_free_descriptor(chan, desc); +} + +static void xgene_dma_free_chan_resources(struct dma_chan *dchan) +{ + struct xgene_dma_chan *chan = to_dma_chan(dchan); + + chan_dbg(chan, "Free all resources\n"); + + if (!chan->desc_pool) + return; + + spin_lock_bh(&chan->lock); + + /* Process all running descriptor */ + xgene_dma_cleanup_descriptors(chan); + + /* Clean all link descriptor queues */ + xgene_dma_free_desc_list(chan, &chan->ld_pending); + xgene_dma_free_desc_list(chan, &chan->ld_running); + xgene_dma_free_desc_list(chan, &chan->ld_completed); + + /* Delete this channel DMA pool */ + dma_pool_destroy(chan->desc_pool); + chan->desc_pool = NULL; + + spin_unlock_bh(&chan->lock); +} + +static struct dma_async_tx_descriptor *xgene_dma_prep_memcpy( + struct dma_chan *dchan, dma_addr_t dst, dma_addr_t src, + size_t len, unsigned long flags) +{ + struct xgene_dma_desc_sw *first = NULL, *new; + struct xgene_dma_chan *chan; + size_t copy; + + if (unlikely(!dchan || (len == 0))) + return NULL; + + chan = to_dma_chan(dchan); + + do { + /* Allocate the link descriptor from DMA pool */ + new = xgene_dma_alloc_descriptor(chan); + if (!new) + goto fail; + + /* Create the largest transaction possible */ + copy = min_t(size_t, len, DMA_MAX_64B_DESC_BYTE_CNT); + + /* Prepare DMA descriptor */ + xgene_dma_prep_cpy_desc(chan, new, dst, src, copy); + + if (!first) + first = new; + + new->tx.cookie = 0; + async_tx_ack(&new->tx); + + /* Update metadata */ + len -= copy; + dst += copy; + src += copy; + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + } while (len); + + new->tx.flags = flags; /* client is in control of this ack */ + new->tx.cookie = -EBUSY; + list_splice(&first->tx_list, &new->tx_list); + + return &new->tx; + +fail: + if (!first) + return NULL; + + xgene_dma_free_desc_list_reverse(chan, &first->tx_list); + return NULL; +} + +static struct dma_async_tx_descriptor *xgene_dma_prep_sg( + struct dma_chan *dchan, struct scatterlist *dst_sg, + unsigned int dst_nents, struct scatterlist *src_sg, + unsigned int src_nents, unsigned long flags) +{ + struct xgene_dma_desc_sw *first = NULL, *new = NULL; + struct xgene_dma_chan *chan; + size_t dst_avail, src_avail; + dma_addr_t dst, src; + size_t len; + + if (unlikely(!dchan)) + return NULL; + + if (unlikely(dst_nents == 0 || src_nents == 0)) + return NULL; + + if (unlikely(!dst_sg || !src_sg)) + return NULL; + + chan = to_dma_chan(dchan); + + /* Get prepared for the loop */ + dst_avail = sg_dma_len(dst_sg); + src_avail = sg_dma_len(src_sg); + dst_nents--; + src_nents--; + + /* Run until we are out of scatterlist entries */ + while (true) { + /* Create the largest transaction possible */ + len = min_t(size_t, src_avail, dst_avail); + len = min_t(size_t, len, DMA_MAX_64B_DESC_BYTE_CNT); + if (len == 0) + goto fetch; + + dst = sg_dma_address(dst_sg) + sg_dma_len(dst_sg) - dst_avail; + src = sg_dma_address(src_sg) + sg_dma_len(src_sg) - src_avail; + + /* Allocate the link descriptor from DMA pool */ + new = xgene_dma_alloc_descriptor(chan); + if (!new) + goto fail; + + /* Prepare DMA descriptor */ + xgene_dma_prep_cpy_desc(chan, new, dst, src, len); + + if (!first) + first = new; + + new->tx.cookie = 0; + async_tx_ack(&new->tx); + + /* update metadata */ + dst_avail -= len; + src_avail -= len; + + /* Insert the link descriptor to the LD ring */ + list_add_tail(&new->node, &first->tx_list); + +fetch: + /* fetch the next dst scatterlist entry */ + if (dst_avail == 0) { + /* no more entries: we're done */ + if (dst_nents == 0) + break; + + /* fetch the next entry: if there are no more: done */ + dst_sg = sg_next(dst_sg); + if (!dst_sg) + break; + + dst_nents--; + dst_avail = sg_dma_len(dst_sg); + } + + /* fetch the next src scatterlist entry */ + if (src_avail == 0) { + /* no more entries: we're done */ + if (src_nents == 0) + break; + + /* fetch the next entry: if there are no more: done */ + src_sg = sg_next(src_sg); + if (!src_sg) + break; + + src_nents--; + src_avail = sg_dma_len(src_sg); + } + } + + if (!new) + return NULL; + + new->tx.flags = flags; /* client is in control of this ack */ + new->tx.cookie = -EBUSY; + list_splice(&first->tx_list, &new->tx_list); + + return &new->tx; + +fail: + if (!first) + return NULL; + + xgene_dma_free_desc_list_reverse(chan, &first->tx_list); + return NULL; +} + +static void xgene_dma_issue_pending(struct dma_chan *dchan) +{ + struct xgene_dma_chan *chan = to_dma_chan(dchan); + + spin_lock_bh(&chan->lock); + xgene_chan_xfer_ld_pending(chan); + spin_unlock_bh(&chan->lock); +} + +static enum dma_status xgene_dma_tx_status(struct dma_chan *dchan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct xgene_dma_chan *chan = to_dma_chan(dchan); + enum dma_status status; + + status = dma_cookie_status(dchan, cookie, txstate); + if (status == DMA_COMPLETE) + return status; + + /* Cleanup any running and executed descriptors */ + spin_lock_bh(&chan->lock); + xgene_dma_cleanup_descriptors(chan); + spin_unlock_bh(&chan->lock); + + return dma_cookie_status(dchan, cookie, txstate); +} + +static void xgene_dma_tasklet_cb(unsigned long data) +{ + struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data; + + spin_lock_bh(&chan->lock); + + /* Run all cleanup for descriptors which have been completed */ + xgene_dma_cleanup_descriptors(chan); + + /* Re-enable DMA channel IRQ */ + enable_irq(chan->rx_irq); + + spin_unlock_bh(&chan->lock); +} + +static irqreturn_t xgene_dma_chan_ring_isr(int irq, void *id) +{ + struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id; + + BUG_ON(!chan); + + /* + * Disable DMA channel IRQ until we process completed + * descriptors + */ + disable_irq_nosync(chan->rx_irq); + + /* + * Schedule the tasklet to handle all cleanup of the current + * transaction. It will start a new transaction if there is + * one pending. + */ + tasklet_schedule(&chan->tasklet); + + return IRQ_HANDLED; +} + +static irqreturn_t xgene_dma_err_isr(int irq, void *id) +{ + struct xgene_dma *pdma = (struct xgene_dma *)id; + unsigned long int_mask; + u32 val, i; + + val = ioread32(pdma->csr_dma + DMA_INT); + + /* Clear DMA interrupts */ + iowrite32(val, pdma->csr_dma + DMA_INT); + + /* Print DMA error info */ + int_mask = val >> DMA_INT_MASK_SHIFT; + for_each_set_bit(i, &int_mask, ARRAY_SIZE(xgene_dma_err)) + dev_err(pdma->dev, + "Interrupt status 0x%08X %s\n", val, xgene_dma_err[i]); + + return IRQ_HANDLED; +} + +static void xgene_dma_wr_ring_state(struct xgene_dma_ring *ring) +{ + int i; + + iowrite32(ring->num, ring->pdma->csr_ring + DMA_RING_STATE); + + for (i = 0; i < DMA_RING_NUM_CONFIG; i++) + iowrite32(ring->state[i], ring->pdma->csr_ring + + DMA_RING_STATE_WR_BASE + (i * 4)); +} + +static void xgene_dma_clr_ring_state(struct xgene_dma_ring *ring) +{ + memset(ring->state, 0, sizeof(u32) * DMA_RING_NUM_CONFIG); + xgene_dma_wr_ring_state(ring); +} + +static void xgene_dma_setup_ring(struct xgene_dma_ring *ring) +{ + void *ring_cfg = ring->state; + u64 addr = ring->desc_paddr; + void *desc; + u32 i, val; + + ring->slots = ring->size / DMA_RING_WQ_DESC_SIZE; + + /* Clear DMA ring state */ + xgene_dma_clr_ring_state(ring); + + /* Set DMA ring type */ + DMA_RING_TYPE_SET(ring_cfg, DMA_RING_TYPE_REGULAR); + + if (ring->owner == DMA_RING_OWNER_DMA) { + /* Set recombination buffer and timeout */ + DMA_RING_RECOMBBUF_SET(ring_cfg); + DMA_RING_RECOMTIMEOUTL_SET(ring_cfg); + DMA_RING_RECOMTIMEOUTH_SET(ring_cfg); + } + + /* Initialize DMA ring state */ + DMA_RING_SELTHRSH_SET(ring_cfg); + DMA_RING_ACCEPTLERR_SET(ring_cfg); + DMA_RING_COHERENT_SET(ring_cfg); + DMA_RING_ADDRL_SET(ring_cfg, addr); + DMA_RING_ADDRH_SET(ring_cfg, addr); + DMA_RING_SIZE_SET(ring_cfg, ring->cfgsize); + + /* Write DMA ring configurations */ + xgene_dma_wr_ring_state(ring); + + /* Set DMA ring id */ + iowrite32(DMA_RING_ID_SETUP(ring->id), + ring->pdma->csr_ring + DMA_RING_ID); + + /* Set DMA ring buffer */ + iowrite32(DMA_RING_ID_BUF_SETUP(ring->num), + ring->pdma->csr_ring + DMA_RING_ID_BUF); + + if (ring->owner != DMA_RING_OWNER_CPU) + return; + + /* Set empty signature to DMA Rx ring descriptors */ + for (i = 0; i < ring->slots; i++) { + desc = &ring->desc_hw[i]; + DMA_DESC_SET_EMPTY(desc); + } + + /* Enable DMA Rx ring interrupt */ + val = ioread32(ring->pdma->csr_ring + DMA_RING_NE_INT_MODE); + DMA_RING_NE_INT_MODE_SET(val, ring->buf_num); + iowrite32(val, ring->pdma->csr_ring + DMA_RING_NE_INT_MODE); +} + +static void xgene_dma_clear_ring(struct xgene_dma_ring *ring) +{ + u32 ring_id, val; + + if (ring->owner == DMA_RING_OWNER_CPU) { + /* Disable DMA Rx ring interrupt */ + val = ioread32(ring->pdma->csr_ring + DMA_RING_NE_INT_MODE); + DMA_RING_NE_INT_MODE_RESET(val, ring->buf_num); + iowrite32(val, ring->pdma->csr_ring + DMA_RING_NE_INT_MODE); + } + + /* Clear DMA ring state */ + ring_id = DMA_RING_ID_SETUP(ring->id); + iowrite32(ring_id, ring->pdma->csr_ring + DMA_RING_ID); + + iowrite32(0, ring->pdma->csr_ring + DMA_RING_ID_BUF); + xgene_dma_clr_ring_state(ring); +} + +static void xgene_dma_set_ring_cmd(struct xgene_dma_ring *ring) +{ + ring->cmd_base = ring->pdma->csr_ring_cmd + + DMA_RING_CMD_BASE_OFFSET((ring->num - DMA_RING_NUM)); + ring->cmd = ring->cmd_base + DMA_RING_CMD_OFFSET; +} + +static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan, + enum xgene_dma_ring_cfgsize cfgsize) +{ + int size; + + switch (cfgsize) { + case DMA_RING_CFG_SIZE_512B: + size = 0x200; + break; + case DMA_RING_CFG_SIZE_2KB: + size = 0x800; + break; + case DMA_RING_CFG_SIZE_16KB: + size = 0x4000; + break; + case DMA_RING_CFG_SIZE_64KB: + size = 0x10000; + break; + case DMA_RING_CFG_SIZE_512KB: + size = 0x80000; + break; + default: + chan_err(chan, "Unsupported cfg ring size %d\n", cfgsize); + return -EINVAL; + } + + return size; +} + +static void xgene_dma_delete_ring_one(struct xgene_dma_ring *ring) +{ + /* Clear DMA ring configurations */ + xgene_dma_clear_ring(ring); + + /* De-allocate DMA ring descriptor */ + if (ring->desc_vaddr) { + dma_free_coherent(ring->pdma->dev, ring->size, + ring->desc_vaddr, ring->desc_paddr); + ring->desc_vaddr = NULL; + } +} + +static void xgene_dma_delete_chan_rings(struct xgene_dma_chan *chan) +{ + xgene_dma_delete_ring_one(&chan->rx_ring); + xgene_dma_delete_ring_one(&chan->tx_ring); +} + +static int xgene_dma_create_ring_one(struct xgene_dma_chan *chan, + struct xgene_dma_ring *ring, + enum xgene_dma_ring_cfgsize cfgsize) +{ + /* Setup DMA ring descriptor variables */ + ring->pdma = chan->pdma; + ring->cfgsize = cfgsize; + ring->num = chan->pdma->ring_num++; + ring->id = DMA_RING_ID_GET(ring->owner, ring->buf_num); + + ring->size = xgene_dma_get_ring_size(chan, cfgsize); + if (ring->size <= 0) + return ring->size; + + /* Allocate memory for DMA ring descriptor */ + ring->desc_vaddr = dma_zalloc_coherent(chan->dev, ring->size, + &ring->desc_paddr, GFP_KERNEL); + if (!ring->desc_vaddr) { + chan_err(chan, "Failed to allocate ring desc\n"); + return -ENOMEM; + } + + /* Configure and enable DMA ring */ + xgene_dma_set_ring_cmd(ring); + xgene_dma_setup_ring(ring); + + return 0; +} + +static int xgene_dma_create_chan_rings(struct xgene_dma_chan *chan) +{ + struct xgene_dma_ring *rx_ring = &chan->rx_ring; + struct xgene_dma_ring *tx_ring = &chan->tx_ring; + int ret; + + /* Create DMA Rx ring descriptor */ + rx_ring->owner = DMA_RING_OWNER_CPU; + rx_ring->buf_num = DMA_CPU_BUFNUM + chan->id; + + ret = xgene_dma_create_ring_one(chan, rx_ring, DMA_RING_CFG_SIZE_64KB); + if (ret) + return ret; + + chan_dbg(chan, "Rx ring id 0x%X num %d desc 0x%p\n", + rx_ring->id, rx_ring->num, rx_ring->desc_vaddr); + + /* Create DMA Tx ring descriptor */ + tx_ring->owner = DMA_RING_OWNER_DMA; + tx_ring->buf_num = DMA_BUFNUM + chan->id; + + ret = xgene_dma_create_ring_one(chan, tx_ring, DMA_RING_CFG_SIZE_64KB); + if (ret) { + xgene_dma_delete_ring_one(rx_ring); + return ret; + } + + tx_ring->dst_ring_num = DMA_RING_DST_ID(rx_ring->num); + + chan_dbg(chan, + "Tx ring id 0x%X num %d desc 0x%p\n", + tx_ring->id, tx_ring->num, tx_ring->desc_vaddr); + + return ret; +} + +static int xgene_dma_init_rings(struct xgene_dma *pdma) +{ + int ret, i, j; + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + ret = xgene_dma_create_chan_rings(&pdma->chan[i]); + if (ret) { + for (j = 0; j < i; j++) + xgene_dma_delete_chan_rings(&pdma->chan[j]); + return ret; + } + } + + return ret; +} + +static void xgene_dma_enable(struct xgene_dma *pdma) +{ + u32 val; + + /* Configure and enable DMA engine */ + val = ioread32(pdma->csr_dma + DMA_GCR); + DMA_CH_SETUP(val); + DMA_ENABLE(val); + iowrite32(val, pdma->csr_dma + DMA_GCR); +} + +static void xgene_dma_disable(struct xgene_dma *pdma) +{ + u32 val; + + val = ioread32(pdma->csr_dma + DMA_GCR); + DMA_DISABLE(val); + iowrite32(val, pdma->csr_dma + DMA_GCR); +} + +static void xgene_dma_mask_interrupts(struct xgene_dma *pdma) +{ + /* + * Mask DMA ring overflow, underflow and + * AXI write/read error interrupts + */ + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT0_MASK); + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT1_MASK); + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT2_MASK); + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT3_MASK); + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_RING_INT4_MASK); + + /* Mask DMA error interrupts */ + iowrite32(DMA_INT_ALL_MASK, pdma->csr_dma + DMA_INT_MASK); +} + +static void xgene_dma_unmask_interrupts(struct xgene_dma *pdma) +{ + /* + * Unmask DMA ring overflow, underflow and + * AXI write/read error interrupts + */ + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT0_MASK); + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT1_MASK); + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT2_MASK); + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT3_MASK); + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_RING_INT4_MASK); + + /* Unmask DMA error interrupts */ + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_INT_MASK); +} + +static void xgene_dma_init_hw(struct xgene_dma *pdma) +{ + u32 val; + + /* Associate DMA ring to corresponding ring HW */ + iowrite32(DMA_ASSOC_RING_MNGR1, + pdma->csr_dma + DMA_CFG_RING_WQ_ASSOC); + + xgene_dma_enable(pdma); + xgene_dma_unmask_interrupts(pdma); + + /* Get DMA id and version info */ + val = ioread32(pdma->csr_dma + DMA_IPBRR); + + /* DMA device info */ + dev_info(pdma->dev, + "X-Gene DMA v%d.%02d.%02d driver registered %d channels", + DMA_REV_NO_RD(val), DMA_BUS_ID_RD(val), + DMA_DEV_ID_RD(val), DMA_MAX_CHANNEL); +} + +int xgene_dma_init_ring_mngr(struct xgene_dma *pdma) +{ + if (ioread32(pdma->csr_ring + DMA_RING_CLKEN) && + (!ioread32(pdma->csr_ring + DMA_RING_SRST))) + return 0; + + iowrite32(0x3, pdma->csr_ring + DMA_RING_CLKEN); + iowrite32(0x0, pdma->csr_ring + DMA_RING_SRST); + + /* Bring up memory */ + iowrite32(0x0, pdma->csr_ring + DMA_RING_MEM_RAM_SHUTDOWN); + + /* Force a barrier */ + ioread32(pdma->csr_ring + DMA_RING_MEM_RAM_SHUTDOWN); + + /* reset may take up to 1ms */ + usleep_range(1000, 1100); + + if (ioread32(pdma->csr_ring + DMA_RING_BLK_MEM_RDY) + != DMA_RING_BLK_MEM_RDY_VAL) { + dev_err(pdma->dev, + "Failed to release ring mngr memory from shutdown\n"); + return -ENODEV; + } + + /* program threshold set 1 and all hysteresis */ + iowrite32(DMA_RING_THRESLD0_SET1_VAL, + pdma->csr_ring + DMA_RING_THRESLD0_SET1); + iowrite32(DMA_RING_THRESLD1_SET1_VAL, + pdma->csr_ring + DMA_RING_THRESLD1_SET1); + iowrite32(DMA_RING_HYSTERESIS_VAL, + pdma->csr_ring + DMA_RING_HYSTERESIS); + + /* Enable QPcore and assign error queue */ + iowrite32(DMA_RING_ENABLE, pdma->csr_ring + DMA_RING_CONFIG); + + return 0; +} + +static int xgene_dma_init_mem(struct xgene_dma *pdma) +{ + int ret; + + ret = xgene_dma_init_ring_mngr(pdma); + if (ret) + return ret; + + /* Bring up memory */ + iowrite32(0x0, pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN); + + /* Force a barrier */ + ioread32(pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN); + + /* reset may take up to 1ms */ + usleep_range(1000, 1100); + + if (ioread32(pdma->csr_dma + DMA_BLK_MEM_RDY) + != DMA_BLK_MEM_RDY_VAL) { + dev_err(pdma->dev, + "Failed to release DMA memory from shutdown\n"); + return -ENODEV; + } + + return 0; +} + +static int xgene_dma_request_irqs(struct xgene_dma *pdma) +{ + struct xgene_dma_chan *chan; + int ret, i, j; + + /* Register DMA error irq */ + ret = devm_request_irq(pdma->dev, pdma->err_irq, xgene_dma_err_isr, + 0, "dma_error", pdma); + if (ret) { + dev_err(pdma->dev, + "Failed to register error IRQ %d\n", pdma->err_irq); + return ret; + } + + /* Register DMA channel rx irq */ + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->chan[i]; + ret = devm_request_irq(chan->dev, chan->rx_irq, + xgene_dma_chan_ring_isr, + 0, chan->name, chan); + if (ret) { + chan_err(chan, "Failed to register Rx IRQ %d\n", + chan->rx_irq); + devm_free_irq(pdma->dev, pdma->err_irq, pdma); + + for (j = 0; j < i; j++) { + chan = &pdma->chan[i]; + devm_free_irq(chan->dev, chan->rx_irq, chan); + } + + return ret; + } + } + + return 0; +} + +static void xgene_dma_free_irqs(struct xgene_dma *pdma) +{ + struct xgene_dma_chan *chan; + int i; + + /* Free DMA device error irq */ + devm_free_irq(pdma->dev, pdma->err_irq, pdma); + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->chan[i]; + devm_free_irq(chan->dev, chan->rx_irq, chan); + } +} + +static void xgene_dma_set_caps(struct xgene_dma_chan *chan, + struct dma_device *dma_dev) +{ + /* Initialize DMA device capability mask */ + dma_cap_zero(dma_dev->cap_mask); + + /* Set DMA device capability */ + dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); + dma_cap_set(DMA_SG, dma_dev->cap_mask); + + /* Set base and prep routines */ + dma_dev->dev = chan->dev; + dma_dev->device_alloc_chan_resources = xgene_dma_alloc_chan_resources; + dma_dev->device_free_chan_resources = xgene_dma_free_chan_resources; + dma_dev->device_issue_pending = xgene_dma_issue_pending; + dma_dev->device_tx_status = xgene_dma_tx_status; + dma_dev->device_prep_dma_memcpy = xgene_dma_prep_memcpy; + dma_dev->device_prep_dma_sg = xgene_dma_prep_sg; +} + +static int xgene_dma_async_register(struct xgene_dma *pdma, int id) +{ + struct xgene_dma_chan *chan = &pdma->chan[id]; + struct dma_device *dma_dev = &pdma->dma_dev[id]; + int ret; + + chan->dma_chan.device = dma_dev; + + spin_lock_init(&chan->lock); + INIT_LIST_HEAD(&chan->ld_pending); + INIT_LIST_HEAD(&chan->ld_running); + INIT_LIST_HEAD(&chan->ld_completed); + tasklet_init(&chan->tasklet, xgene_dma_tasklet_cb, + (unsigned long)chan); + + chan->pending = 0; + chan->desc_pool = NULL; + dma_cookie_init(&chan->dma_chan); + + /* Setup dma device capabilities and prep routines */ + xgene_dma_set_caps(chan, dma_dev); + + /* Initialize DMA device list head */ + INIT_LIST_HEAD(&dma_dev->channels); + list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels); + + /* Register with Linux async DMA framework*/ + ret = dma_async_device_register(dma_dev); + if (ret) { + chan_err(chan, "Failed to register async device %d", ret); + tasklet_kill(&chan->tasklet); + + return ret; + } + + /* DMA capability info */ + dev_info(pdma->dev, + "%s: CAPABILITY ( %s%s)\n", dma_chan_name(&chan->dma_chan), + dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "MEMCPY " : "", + dma_has_cap(DMA_SG, dma_dev->cap_mask) ? "SGCPY " : ""); + + return 0; +} + +static int xgene_dma_init_async(struct xgene_dma *pdma) +{ + int ret, i, j; + + for (i = 0; i < DMA_MAX_CHANNEL ; i++) { + ret = xgene_dma_async_register(pdma, i); + if (ret) { + for (j = 0; j < i; j++) { + dma_async_device_unregister(&pdma->dma_dev[j]); + tasklet_kill(&pdma->chan[j].tasklet); + } + + return ret; + } + } + + return ret; +} + +static void xgene_dma_async_unregister(struct xgene_dma *pdma) +{ + int i; + + for (i = 0; i < DMA_MAX_CHANNEL; i++) + dma_async_device_unregister(&pdma->dma_dev[i]); +} + +static void xgene_dma_init_channels(struct xgene_dma *pdma) +{ + struct xgene_dma_chan *chan; + int i; + + pdma->ring_num = DMA_RING_NUM; + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->chan[i]; + chan->dev = pdma->dev; + chan->pdma = pdma; + chan->id = i; + sprintf(chan->name, "chan%d", chan->id); + } +} + +static int xgene_dma_get_resources(struct platform_device *pdev, + struct xgene_dma *pdma) +{ + struct resource *res; + int irq, i; + + /* Get DMA csr region */ + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma_csr"); + if (!res) { + dev_err(&pdev->dev, "Failed to get csr region\n"); + return -ENXIO; + } + + pdma->csr_dma = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (IS_ERR(pdma->csr_dma)) { + dev_err(&pdev->dev, "Failed to ioremap csr region"); + return PTR_ERR(pdma->csr_dma); + } + + /* Get DMA ring csr region */ + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ring_csr"); + if (!res) { + dev_err(&pdev->dev, "Failed to get ring csr region\n"); + return -ENXIO; + } + + pdma->csr_ring = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (IS_ERR(pdma->csr_ring)) { + dev_err(&pdev->dev, "Failed to ioremap ring csr region"); + return PTR_ERR(pdma->csr_ring); + } + + /* Get DMA ring cmd csr region */ + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, + "ring_cmd_csr"); + if (!res) { + dev_err(&pdev->dev, "Failed to get ring cmd csr region\n"); + return -ENXIO; + } + + pdma->csr_ring_cmd = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (IS_ERR(pdma->csr_ring_cmd)) { + dev_err(&pdev->dev, "Failed to ioremap ring cmd csr region"); + return PTR_ERR(pdma->csr_ring_cmd); + } + + /* Get DMA error interrupt */ + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + dev_err(&pdev->dev, "Failed to get Error IRQ\n"); + return -ENXIO; + } + + pdma->err_irq = irq; + + /* Get DMA Rx ring descriptor interrupts for all DMA channels */ + for (i = 1; i <= DMA_MAX_CHANNEL; i++) { + irq = platform_get_irq(pdev, i); + if (irq <= 0) { + dev_err(&pdev->dev, "Failed to get Rx IRQ\n"); + return -ENXIO; + } + + pdma->chan[i - 1].rx_irq = irq; + } + + return 0; +} + +static int xgene_dma_probe(struct platform_device *pdev) +{ + struct xgene_dma *pdma; + int ret, i; + + pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL); + if (!pdma) + return -ENOMEM; + + pdma->dev = &pdev->dev; + platform_set_drvdata(pdev, pdma); + + ret = xgene_dma_get_resources(pdev, pdma); + if (ret) + return ret; + + pdma->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pdma->clk)) { + dev_err(&pdev->dev, "Failed to get clk\n"); + return PTR_ERR(pdma->clk); + } + + /* Enable clk before accessing registers */ + ret = clk_prepare_enable(pdma->clk); + if (ret) { + dev_err(&pdev->dev, "Failed to enable clk %d\n", ret); + return ret; + } + + /* Remove DMA RAM out of shutdown */ + ret = xgene_dma_init_mem(pdma); + if (ret) + goto err_clk_enable; + + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(42)); + if (ret) { + dev_err(&pdev->dev, "No usable DMA configuration\n"); + goto err_dma_mask; + } + + /* Initialize DMA channels software state */ + xgene_dma_init_channels(pdma); + + /* Configue DMA rings */ + ret = xgene_dma_init_rings(pdma); + if (ret) + goto err_clk_enable; + + ret = xgene_dma_request_irqs(pdma); + if (ret) + goto err_request_irq; + + /* Configure and enable DMA engine */ + xgene_dma_init_hw(pdma); + + /* Register DMA device with linux async framework */ + ret = xgene_dma_init_async(pdma); + if (ret) + goto err_async_init; + + return 0; + +err_async_init: + xgene_dma_free_irqs(pdma); + +err_request_irq: + for (i = 0; i < DMA_MAX_CHANNEL; i++) + xgene_dma_delete_chan_rings(&pdma->chan[i]); + +err_dma_mask: +err_clk_enable: + clk_disable_unprepare(pdma->clk); + + return ret; +} + +static int xgene_dma_remove(struct platform_device *pdev) +{ + struct xgene_dma *pdma = platform_get_drvdata(pdev); + struct xgene_dma_chan *chan; + int i; + + xgene_dma_async_unregister(pdma); + + /* Mask interrupts and disable DMA engine */ + xgene_dma_mask_interrupts(pdma); + xgene_dma_disable(pdma); + xgene_dma_free_irqs(pdma); + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->chan[i]; + tasklet_kill(&chan->tasklet); + xgene_dma_delete_chan_rings(chan); + } + + clk_disable_unprepare(pdma->clk); + + return 0; +} + +static const struct of_device_id xgene_dma_of_match_ptr[] = { + {.compatible = "apm,xgene-dma",}, + {}, +}; +MODULE_DEVICE_TABLE(of, xgene_dma_of_match_ptr); + +static struct platform_driver xgene_dma_driver = { + .probe = xgene_dma_probe, + .remove = xgene_dma_remove, + .driver = { + .name = "X-Gene-DMA", + .owner = THIS_MODULE, + .of_match_table = xgene_dma_of_match_ptr, + }, +}; + +module_platform_driver(xgene_dma_driver); + +MODULE_DESCRIPTION("APM X-Gene SoC DMA driver"); +MODULE_AUTHOR("Rameshwar Prasad Sahu <rsahu@xxxxxxx>"); +MODULE_AUTHOR("Loc Ho <lho@xxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1.0"); -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
