This patch implements the APM X-Gene SoC DMA 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 gathering offload. 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 | 1506 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1515 insertions(+) create mode 100644 drivers/dma/xgene-dma.c diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index f2b2c4e..251ce60 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -416,6 +416,14 @@ config NBPFAXI_DMA help Support for "Type-AXI" NBPF DMA IPs from Renesas +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 2022b54..0567e69 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -50,3 +50,4 @@ obj-y += xilinx/ 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_XGENE_DMA) += xgene-dma.o diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c new file mode 100644 index 0000000..e00c062 --- /dev/null +++ b/drivers/dma/xgene-dma.c @@ -0,0 +1,1506 @@ +/* Applied Micro X-Gene SoC DMA engine Driver + * + * Copyright (c) 2014, 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/>. + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/highmem.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/pm_runtime.h> + +#include "dmaengine.h" + +/* DMA ring csr registers and bit definations */ +#define RING_ID 0x0008 +#define RING_ID_BUF 0x000c +#define RING_CONFIG 0x006c +#define RING_WR_BASE 0x0070 +#define RING_NE_INT_MODE 0x017c +#define RING_NUM_CONFIG 5 +#define RING_DST_RING_ID(v) ((1 << 10) | (v)) +#define RING_CMD_OFFSET(v) (((v) << 6) + 0x2C) +#define RING_SELTHRSH_SET(m) (((u32 *)(m))[4] |= BIT(3)) +#define RING_ACCEPTLERR_SET(m) (((u32 *)(m))[3] |= BIT(19)) +#define RING_QCOHERENT_SET(m) (((u32 *)(m))[2] |= BIT(4)) +#define RING_RECOMBBUF_SET(m) (((u32 *)(m))[3] |= BIT(27)) +#define RING_ID_SETUP(v) ((v) | BIT(31)) +#define RING_ID_BUF_SETUP(v) (((v) << 9) | BIT(21)) +#define RING_ID_GET(owner, num) (((owner) << 6) | (num)) +#define RING_ADDRL_SET(m, v) (((u32 *)(m))[2] |= (((v) >> 8) << 5)) +#define RING_ADDRH_SET(m, v) (((u32 *)(m))[3] |= ((v) >> 35)) +#define RING_SIZE_SET(m, v) (((u32 *)(m))[3] |= ((v) << 23)) +#define RING_TYPE_SET(m, v) (((u32 *)(m))[4] |= ((v) << 19)) +#define RING_RECOMTIMEOUTL_SET(m) \ + (((u32 *)(m))[3] |= (0x7 << 28)) +#define RINNG_RECOMTIMEOUTH_SET(m) \ + (((u32 *)(m))[4] |= 0x3) +#define RING_NE_INT_MODE_SET(m, v) \ + ((m) = ((m) & ~BIT(31 - (v))) | BIT(31 - (v))) +#define RING_NE_INT_MODE_RESET(m, v) \ + ((m) &= (~BIT(31 - (v)))) + +/* DMA device csr registers and bit definitions */ +#define DMA_MEM_RAM_SHUTDOWN 0xD070 +#define DMA_BLK_MEM_RDY 0xD074 +#define DMA_BLK_MEM_RDY_DEFAULT 0xFFFFFFFF +#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_WQ_ASSOC_RING_MNGR1 0xFFFFFFFF +#define DMA_CFG_RING_HOLD 0x90F8 +#define DMA_RING_MNGR1_HOLD_EN BIT(1) +#define DMA_IPBRR 0x0 +#define DMA_BUS_ID_RD(v) (((v) >> 12) & 3) +#define DMA_REV_NO_RD(v) (((v) >> 14) & 3) +#define DMA_DEVICE_ID_RD(v) ((v) & 0x00000FFF) +#define DMA_INT 0x70 +#define DMA_INT_MASK 0x74 +#define DMA_INT_ALL_UNMASK 0x0 +#define DMA_INT_MASK_SHIFT 0x14 +#define DMA_GCR 0x10 +#define DMA_CH_SETUP(m) ((m) = ((m) & ~0x000FFFFF) | 0x000AAFFF) +#define DMA_ENABLE(m) ((m) = ((m) & ~BIT(31)) | BIT(31)) + +/* Descriptor ring format */ +#define RING_DESC_UINFO_RD(m) (u32)((m) & 0xFFFFFFFF) +#define RING_DESC_UINFO_SET(m, v) (((u64 *)(m))[0] |= (v)) +#define RING_DESC_LERR_RD(m) (((m) >> 60) & 0x7) +#define RING_DESC_RTYPE_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 56)) +#define RING_DESC_NV_SET(m) (((u64 *)(m))[0] |= BIT_ULL(50)) +#define RING_DESC_ELERR_RD(m) (((m) >> 46) & 0x3) +#define RING_DESC_STATUS(x, y) (((x) << 4) | (y)) +#define RING_DESC_C_SET(m) (((u64 *)(m))[1] |= BIT_ULL(63)) +#define RING_DESC_DR_SET(m) (((u64 *)(m))[2] |= BIT_ULL(61)) +#define RING_DESC_DST_ADDR_SET(m, v) (((u64 *)(m))[3] |= (v)) +#define RING_DESC_H0ENQ_NUM_SET(m, v) (((u64 *)(m))[3] |= ((u64)(v) << 48)) +#define RING_DESC_BUFADDR_SET(m, v) (((u64 *)(m))[0] |= (v)) +#define RING_DESC_BUFLEN_SET(m, v) (((u64 *)(m))[0] |= ((u64)(v) << 48)) + +/* Descriptor ring empty s/w signature */ +#define RING_DESC_EMPTY_INDEX 0 +#define RING_DESC_EMPTY_SIGNATURE ~0ULL +#define RING_DESC_IS_EMPTY(m) \ + (((u64 *)(m))[RING_DESC_EMPTY_INDEX] == RING_DESC_EMPTY_SIGNATURE) +#define RING_DESC_SET_EMPTY(m) \ + (((u64 *)(m))[RING_DESC_EMPTY_INDEX] = RING_DESC_EMPTY_SIGNATURE) + +/* DMA ring descriptor hex dump */ +#define RING_DESC_ERR_DUMP(desc) \ + print_hex_dump(KERN_ERR, "X-Gene DMA: Rx ERR DESC ", \ + DUMP_PREFIX_ADDRESS, 16, 8, (desc), 32, 0) + +/* DMA channel configurations */ +#define DMA_MAX_CHANNEL 4 +#define DMA_SLOT_PER_CHANNEL 64 +#define DMA_CHANNEL_BUDGET 1024 +#define DMA_MAX_RING_DESC_CNT_PER_SLOT 32 +#define DMA_MAX_BYTE_CNT 0x4000 /* 16 KB */ +#define DMA_MAX_64B_DESC_BYTE_CNT 0x14000 /* 80KB */ +#define DMA_MAX_MEMCPY_BYTE_CNT 0x140000 /* 1280KB */ +#define DMA_MAX_SG_BYTE_CNT 0x80000 /* 512KB */ +#define DMA_16K_BUFFER_LEN_CODE 0x0 +#define DMA_INVALID_LEN_CODE 0x7800 + +/* DMA ring Configurations */ +#define START_DMA_RING_NUM 512 +#define START_DMA_BUFNUM 0x00 +#define START_CPU_BUFNUM 0x18 +#define RING_OWNER_DMA 0x03 +#define RING_OWNER_CPU 0x0F +#define RING_TYPE_REGULAR 0x01 + +/* DMA channel slot flags */ +#define FLAG_SG_ACTIVE BIT(1) +#define FLAG_SLOT_IN_USE BIT(2) + +/* DMA ring 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 0x10 +#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 + +/* DMA ring descriptor */ +struct xgene_dma_ring_desc { + u64 m0; + u64 m1; + u64 m2; + u64 m3; +}; + +/* DMA ring configurable size */ +enum xgene_dma_ring_cfgsize { + RING_CFG_SIZE_512B, + RING_CFG_SIZE_2KB, + RING_CFG_SIZE_16KB, + RING_CFG_SIZE_64KB, + RING_CFG_SIZE_512KB, + RING_CFG_SIZE_INVALID +}; + +/* DMA ring descriptor */ +struct xgene_dma_ring_info { + struct xgene_dma *pdma; + u8 buf_num; + u16 id; + u16 num; + u16 head; + u16 owner; + u16 slots; + u32 size; + void __iomem *cmd; + dma_addr_t desc_paddr; + u32 state[RING_NUM_CONFIG]; + enum xgene_dma_ring_cfgsize cfgsize; + union { + void *desc_vaddr; + struct xgene_dma_ring_desc *desc; + }; +}; + +/* DMA slot descriptor */ +struct xgene_dma_slot { + u32 index; + u32 flags; + u32 status; + u32 desc_cnt; + struct dma_async_tx_descriptor async_tx; + + /* Shadow copy to use in submit */ + dma_addr_t dst; + dma_addr_t src; + size_t len; + + /* Scatter/Gather shadow copy to use in submit */ + struct scatterlist *srcdst_list; + u32 src_nents; +}; + +/* DMA channel descriptor */ +struct xgene_dma_chan { + struct dma_chan dma_chan; + struct xgene_dma *pdma; + int index; + int rx_irq; + int tx_cmd; + char name[16]; + spinlock_t lock; /* DMA Channel lock */ + struct xgene_dma_ring_info tx_ring; + struct xgene_dma_ring_info rx_ring; + struct tasklet_struct rx_tasklet; + struct xgene_dma_slot *slots; + struct xgene_dma_slot *last_used; +}; + +/* DMA device */ +struct xgene_dma { + struct device *dev; + struct clk *dma_clk; + int irq; /* Error IRQ */ + int ring_num; + void __iomem *csr_dma; + void __iomem *csr_ring; + void __iomem *csr_ring_cmd; + struct dma_device dma_dev; + struct xgene_dma_chan channels[DMA_MAX_CHANNEL]; +}; + +static const char * const xgene_dma_ring_desc_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 the descriptor", + [ERR_READ_DATA_AXI] = "AXI error when reading data", + [ERR_WRITE_DATA_AXI] = "AXI error when writing data", + [ERR_FBP_TIMEOUT] = "Timeout on free pool buffer fetch", + [ERR_ECC] = "ECC double bit error", + [ERR_DIFF_SIZE] = + "Free pool buffer too small to hold all the DIF result", + [ERR_SCT_GAT_LEN] = + "Gather and scatter don't have the same data length", + [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 destination link address error", + [ERR_DESC_SRC_INT] = "HFB reading source link address error", +}; + +#define to_xgene_dma_chan(chan) \ + container_of(chan, struct xgene_dma_chan, dma_chan) +#define tx_to_xgene_dma_slot(tx) \ + container_of(tx, struct xgene_dma_slot, async_tx) + +static void xgene_dma_cpu_to_le64(u64 *desc) +{ + int i; + + for (i = 0; i < 4; 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_encode_uinfo(struct xgene_dma_slot *slot) +{ + return slot->index; +} + +static void *xgene_dma_decode_uinfo(struct xgene_dma_chan *chan, + u32 uinfo) +{ + return ((uinfo < DMA_SLOT_PER_CHANNEL) ? + &chan->slots[uinfo] : NULL); +} + +static void xgene_dma_process_desc(struct xgene_dma_chan *chan, + struct xgene_dma_ring_desc *desc) +{ + struct xgene_dma_slot *slot; + + /* Get the DMA channel slot */ + slot = xgene_dma_decode_uinfo(chan, + RING_DESC_UINFO_RD( + le64_to_cpu(desc->m0))); + if (unlikely(!slot)) { + dev_err(chan->pdma->dev, + "Channel %d invalid uinfo %d\n", + chan->index, RING_DESC_UINFO_RD(le64_to_cpu(desc->m0))); + return; + } + + /* Check the descriptor if any error */ + slot->status = RING_DESC_STATUS( + RING_DESC_ELERR_RD(le64_to_cpu(desc->m0)), + RING_DESC_LERR_RD(le64_to_cpu(desc->m0))); + if (slot->status) { + dev_err(chan->pdma->dev, + "channel %d slot %d %s (tag=%p)\n", chan->index, + slot->index, xgene_dma_ring_desc_err[slot->status], + slot->async_tx.callback_param); + RING_DESC_ERR_DUMP(desc); + } + + /* Check whether we have completed all descriptor */ + if (--slot->desc_cnt == 0) { + dma_cookie_complete(&slot->async_tx); + + /* call the client callback function */ + if (slot->async_tx.callback) + slot->async_tx.callback( + slot->async_tx.callback_param); + + dma_descriptor_unmap(&slot->async_tx); + + if (slot->flags & FLAG_SG_ACTIVE) { + devm_kfree(chan->pdma->dev, slot->srcdst_list); + slot->srcdst_list = NULL; + } + + slot->flags = 0; + + /* run dependent operations */ + dma_run_dependencies(&slot->async_tx); + } +} + +static void xgene_dma_tasklet_cb(unsigned long data) +{ + struct xgene_dma_chan *chan = (struct xgene_dma_chan *)data; + struct xgene_dma_ring_info *ring = &chan->rx_ring; + struct xgene_dma_ring_desc *desc; + u32 budget = DMA_CHANNEL_BUDGET; + u32 rx_cmd = 0; + + do { + /* Get completed descriptor */ + desc = &ring->desc[ring->head]; + + /* Check for completed descriptor */ + if (unlikely(RING_DESC_IS_EMPTY(desc))) + break; + + ring->head = (ring->head + 1) % ring->slots; + --rx_cmd; + + /* Process completed DMA channel slots */ + xgene_dma_process_desc(chan, desc); + + /* Mark descriptor as empty */ + RING_DESC_SET_EMPTY(desc); + } while (--budget); + + dev_dbg(chan->pdma->dev, + "Channel %d processed %d 32B desc Tx ring id 0x%X Rx ring id 0x%X\n", + chan->index, rx_cmd, chan->tx_ring.id, ring->id); + + if (likely(rx_cmd)) + iowrite32(rx_cmd, ring->cmd); + + /* Re-enable DMA channel IRQ */ + enable_irq(chan->rx_irq); +} + +static irqreturn_t xgene_dma_ring_isr(int irq, void *id) +{ + struct xgene_dma_chan *chan = (struct xgene_dma_chan *)id; + + BUG_ON(!chan); + + /* Disable DMA channel IRQ */ + disable_irq_nosync(chan->rx_irq); + + /* Schedule tasklet */ + tasklet_schedule(&chan->rx_tasklet); + + return IRQ_HANDLED; +} + +static void xgene_dma_write_ring_state(struct xgene_dma_ring_info *ring) +{ + int i; + + iowrite32(ring->num, ring->pdma->csr_ring + RING_CONFIG); + + for (i = 0; i < RING_NUM_CONFIG; i++) + iowrite32(ring->state[i], ring->pdma->csr_ring + + RING_WR_BASE + (i * 4)); +} + +static void xgene_dma_clr_ring_state(struct xgene_dma_ring_info *ring) +{ + memset(ring->state, 0, sizeof(u32) * RING_NUM_CONFIG); + xgene_dma_write_ring_state(ring); +} + +static void xgene_dma_setup_ring(struct xgene_dma_ring_info *ring) +{ + void *ring_cfg = ring->state; + u64 addr = ring->desc_paddr; + void *desc; + u32 i, val; + + /* Clear DMA ring state */ + xgene_dma_clr_ring_state(ring); + + /* Set DMA ring type */ + RING_TYPE_SET(ring_cfg, RING_TYPE_REGULAR); + + /* Set recombination buffer and timeout value */ + if (ring->owner == RING_OWNER_DMA) { + RING_RECOMBBUF_SET(ring_cfg); + RING_RECOMTIMEOUTL_SET(ring_cfg); + RINNG_RECOMTIMEOUTH_SET(ring_cfg); + } + + /* Initialize DMA ring state */ + RING_SELTHRSH_SET(ring_cfg); + RING_ACCEPTLERR_SET(ring_cfg); + RING_QCOHERENT_SET(ring_cfg); + RING_ADDRL_SET(ring_cfg, addr); + RING_ADDRH_SET(ring_cfg, addr); + RING_SIZE_SET(ring_cfg, ring->cfgsize); + + /* Write DMA ring configurations */ + xgene_dma_write_ring_state(ring); + + /* Set DMA ring id */ + iowrite32(RING_ID_SETUP(ring->id), + ring->pdma->csr_ring + RING_ID); + iowrite32(RING_ID_BUF_SETUP(ring->num), + ring->pdma->csr_ring + RING_ID_BUF); + + ring->slots = ring->size / 32; + + if (ring->owner != RING_OWNER_CPU) + return; + + /* Set empty signature to DMA Rx ring descriptors */ + for (i = 0; i < ring->slots; i++) { + desc = &ring->desc[i]; + RING_DESC_SET_EMPTY(desc); + } + + /* Enable DMA Rx ring interrupt */ + val = ioread32(ring->pdma->csr_ring + RING_NE_INT_MODE); + RING_NE_INT_MODE_SET(val, ring->buf_num); + iowrite32(val, ring->pdma->csr_ring + RING_NE_INT_MODE); +} + +static void xgene_dma_clear_ring(struct xgene_dma_ring_info *ring) +{ + u32 val; + + if (ring->owner == RING_OWNER_CPU) { + /* Disable DMA Rx ring interrupt */ + val = ioread32(ring->pdma->csr_ring + RING_NE_INT_MODE); + RING_NE_INT_MODE_RESET(val, ring->buf_num); + iowrite32(val, ring->pdma->csr_ring + RING_NE_INT_MODE); + } + + /* Clear DMA ring state */ + iowrite32(RING_ID_SETUP(ring->id), ring->pdma->csr_ring + RING_ID); + iowrite32(0, ring->pdma->csr_ring + RING_ID_BUF); + xgene_dma_clr_ring_state(ring); +} + +/* Setup DMA ring cmd base address */ +static void xgene_dma_set_ring_cmd(struct xgene_dma_ring_info *ring) +{ + ring->cmd = ring->pdma->csr_ring_cmd + + RING_CMD_OFFSET((ring->num - START_DMA_RING_NUM)); +} + +static int xgene_dma_get_ring_size(struct xgene_dma_chan *chan, + enum xgene_dma_ring_cfgsize cfgsize) +{ + int size; + + switch (cfgsize) { + case RING_CFG_SIZE_512B: + size = 0x200; + break; + case RING_CFG_SIZE_2KB: + size = 0x800; + break; + case RING_CFG_SIZE_16KB: + size = 0x4000; + break; + case RING_CFG_SIZE_64KB: + size = 0x10000; + break; + case RING_CFG_SIZE_512KB: + size = 0x80000; + break; + default: + dev_err(chan->pdma->dev, + "Channel %d Unsupported cfg ring size %d\n", + chan->index, cfgsize); + return -EINVAL; + } + + return size; +} + +static void xgene_dma_delete_ring_one(struct xgene_dma_ring_info *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_info *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 = 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->pdma->dev, ring->size, + &ring->desc_paddr, GFP_KERNEL); + if (!ring->desc_vaddr) { + dev_err(chan->pdma->dev, + "Channel %d failed to allocate ring desc\n", + chan->index); + 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_info *rx_ring = &chan->rx_ring; + struct xgene_dma_ring_info *tx_ring = &chan->tx_ring; + int ret; + + /* Create DMA Rx ring descriptor */ + rx_ring->owner = RING_OWNER_CPU; + rx_ring->buf_num = START_CPU_BUFNUM + chan->index; + + ret = xgene_dma_create_ring_one(chan, rx_ring, RING_CFG_SIZE_64KB); + if (ret) + return ret; + + dev_dbg(chan->pdma->dev, + "Channel %d Rx ring id 0x%X num %d desc 0x%p\n", + chan->index, rx_ring->id, rx_ring->num, rx_ring->desc_vaddr); + + /* Create DMA Tx ring descriptor */ + tx_ring->owner = RING_OWNER_DMA; + tx_ring->buf_num = START_DMA_BUFNUM + chan->index; + + ret = xgene_dma_create_ring_one(chan, tx_ring, RING_CFG_SIZE_64KB); + if (ret) + goto err; + + dev_dbg(chan->pdma->dev, + "Channel %d Tx ring id 0x%X num %d desc 0x%p\n", + chan->index, tx_ring->id, tx_ring->num, tx_ring->desc_vaddr); + + return ret; + +err: + /* Delete DMA Rx ring descriptor created for this DMA channel */ + xgene_dma_delete_ring_one(rx_ring); + 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->channels[i]); + if (ret) + goto err; + } + + return ret; + +err: + /* Delete DMA rings created for other channels */ + for (j = 0; j < i; j++) + xgene_dma_delete_chan_rings(&pdma->channels[j]); + + return ret; +} + +static void xgene_dma_init_hw(struct xgene_dma *pdma) +{ + u32 val; + + /* + * 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); + + /* Associate DMA ring to corresponding ring HW */ + iowrite32(DMA_WQ_ASSOC_RING_MNGR1, + pdma->csr_dma + DMA_CFG_RING_WQ_ASSOC); + iowrite32(DMA_RING_MNGR1_HOLD_EN, + pdma->csr_dma + DMA_CFG_RING_HOLD); + + /* Configure and enable DMA channels */ + val = ioread32(pdma->csr_dma + DMA_GCR); + DMA_CH_SETUP(val); + DMA_ENABLE(val); + iowrite32(val, pdma->csr_dma + DMA_GCR); + + /* Unmask DMA error interrupts */ + iowrite32(DMA_INT_ALL_UNMASK, pdma->csr_dma + DMA_INT_MASK); + + /* 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_DEVICE_ID_RD(val), DMA_MAX_CHANNEL); +} + +static int xgene_dma_init_mem(struct xgene_dma *pdma) +{ + int timeout = 1000; + + writel(0x0, pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN); + + /* Force a barrier */ + readl(pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN); + + do { + if (readl(pdma->csr_dma + DMA_BLK_MEM_RDY) + == DMA_BLK_MEM_RDY_DEFAULT) + break; + udelay(1); + } while (--timeout); + + if (timeout <= 0) { + dev_err(pdma->dev, + "Failed to release memory from shutdown\n"); + return -ENODEV; + } + return 0; +} + +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); + + /* 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, + "%s Interrupt 0x%08X\n", xgene_dma_err[i], val); + + return IRQ_HANDLED; +} + +static int xgene_dma_alloc_chan_resources(struct dma_chan *channel) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(channel); + int i; + + /* Check if we have already allcated resources */ + if (chan->slots) + return DMA_SLOT_PER_CHANNEL; + + spin_lock_bh(&chan->lock); + + chan->slots = devm_kzalloc(chan->pdma->dev, + sizeof(struct xgene_dma_slot) * + DMA_SLOT_PER_CHANNEL, GFP_ATOMIC); + if (!chan->slots) { + spin_unlock_bh(&chan->lock); + dev_err(chan->pdma->dev, + "Channel %d failed to allocate memory for resources\n", + chan->index); + return -ENOMEM; + } + + /* Setup DMA channel resources */ + for (i = 0; i < DMA_SLOT_PER_CHANNEL; i++) { + chan->slots[i].index = i; + chan->slots[i].flags = 0; + chan->slots[i].async_tx.cookie = 0; + dma_async_tx_descriptor_init(&chan->slots[i].async_tx, channel); + } + + chan->last_used = &chan->slots[0]; + dma_cookie_init(&chan->dma_chan); + + dev_dbg(chan->pdma->dev, + "Channel %d allocated %d slot descriptors (size %d) @0x%p\n", + chan->index, DMA_SLOT_PER_CHANNEL, + (int)sizeof(struct xgene_dma_slot), &chan->slots[0]); + + spin_unlock_bh(&chan->lock); + + return DMA_SLOT_PER_CHANNEL; +} + +static void xgene_dma_free_chan_resources(struct dma_chan *channel) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(channel); + + spin_lock_bh(&chan->lock); + + /* Check if we have already free resources */ + if (chan->slots) + devm_kfree(chan->pdma->dev, chan->slots); + + /* Mark channel resources free */ + chan->slots = NULL; + chan->last_used = NULL; + + dev_dbg(chan->pdma->dev, + "Channel %d free %d slot descriptors\n", + chan->index, DMA_SLOT_PER_CHANNEL); + + spin_unlock_bh(&chan->lock); +} + +static enum dma_status xgene_dma_tx_status(struct dma_chan *channel, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + return dma_cookie_status(channel, cookie, txstate); +} + +static void xgene_dma_issue_pending(struct dma_chan *channel) +{ + /* Nothing to do */ +} + +static struct xgene_dma_slot *xgene_dma_get_channel_slot( + struct xgene_dma_chan *chan) +{ + struct xgene_dma_slot *slot; + + slot = (chan->last_used == + (&chan->slots[DMA_SLOT_PER_CHANNEL - 1]) ? + &chan->slots[0] : (chan->last_used + 1)); + + /* Check if slot is already in use */ + if (slot->flags & FLAG_SLOT_IN_USE) { + dev_dbg(chan->pdma->dev, + "Channel %d: No Slot\n", chan->index); + return NULL; + } + + chan->last_used = slot; + slot->async_tx.cookie = -EBUSY; + + return slot; +} + +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); + + RING_DESC_BUFADDR_SET(ext8, *paddr); + RING_DESC_BUFLEN_SET(ext8, xgene_dma_encode_len(*len)); + *len -= nbytes; + *paddr += nbytes; +} + +static void xgene_dma_invalidate_buffer(void *ext8) +{ + RING_DESC_BUFLEN_SET(ext8, DMA_INVALID_LEN_CODE); +} + +static void *xgene_dma_lookup_ext8(void *desc, int idx) +{ + return ((idx % 2) ? ((u64 *)desc + (idx - 1)) : + ((u64 *)desc + (idx + 1))); +} + +static void xgene_dma_init_ring_desc(struct xgene_dma_chan *chan, + struct xgene_dma_slot *slot, + void *desc) +{ + RING_DESC_C_SET(desc); /* Coherent IO */ + RING_DESC_DR_SET(desc); + RING_DESC_RTYPE_SET(desc, RING_OWNER_DMA); + RING_DESC_UINFO_SET(desc, xgene_dma_encode_uinfo(slot)); + RING_DESC_H0ENQ_NUM_SET(desc, + RING_DST_RING_ID(chan->rx_ring.num)); +} + +static void xgene_dma_prep_desc(struct xgene_dma_chan *chan, + struct xgene_dma_slot *slot, + dma_addr_t dst, dma_addr_t src, + size_t len) +{ + struct xgene_dma_ring_info *ring = &chan->tx_ring; + void *dst_virt, *src_virt; + u32 dst_off, src_off; + void *desc1, *desc2; + int i; + + /* + * Size of the DMA ring descriptor is limited to 32 * 32B + * per DMA channel slot. So software memcpy is used for copy + * operations of rest of the buffer beyond this limit. + */ + if (chan->tx_cmd >= + ((len > DMA_MAX_BYTE_CNT) ? + (DMA_MAX_RING_DESC_CNT_PER_SLOT - 1) : + DMA_MAX_RING_DESC_CNT_PER_SLOT)) + goto sw_memcpy; + + /* Get DMA ring descriptor */ + desc1 = &ring->desc[ring->head]; + ring->head = (ring->head + 1) % ring->slots; + memset(desc1, 0, 32); + + /* Initialize DMA ring descriptor */ + xgene_dma_init_ring_desc(chan, slot, desc1); + + /* Set destination address */ + RING_DESC_DST_ADDR_SET(desc1, dst); + + /* Set 1st source address */ + xgene_dma_set_src_buffer(desc1 + 8, &len, &src); + + if (len <= 0) { + desc2 = NULL; + chan->tx_cmd++; + goto skip_additional_src; + } + + /* Get next DMA ring descriptor */ + desc2 = &ring->desc[ring->head]; + ring->head = (ring->head + 1) % ring->slots; + memset(desc2, 0, 32); + + RING_DESC_NV_SET(desc1); + chan->tx_cmd += 2; + + /* 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)); + +skip_additional_src: + slot->desc_cnt++; + + /* Hardware stores descriptor in little endian format */ + xgene_dma_cpu_to_le64(desc1); + if (desc2) + xgene_dma_cpu_to_le64(desc2); + + return; + +sw_memcpy: + dev_dbg(chan->pdma->dev, + "Out of ring descriptor, so using sw memcpy\n"); + dev_dbg(chan->pdma->dev, + "dst 0x%llX src 0x%llX len 0x%zX\n", dst, src, len); + + dst_virt = kmap_atomic(phys_to_page(dst)); + src_virt = kmap_atomic(phys_to_page(src)); + + dst_off = dst & ~PAGE_MASK; + src_off = src & ~PAGE_MASK; + + memcpy(dst_virt + dst_off, src_virt + src_off, len); + + kunmap_atomic(dst_virt); + kunmap_atomic(src_virt); +} + +static dma_cookie_t xgene_dma_tx_memcpy_submit( + struct dma_async_tx_descriptor *tx) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(tx->chan); + struct xgene_dma_slot *slot = tx_to_xgene_dma_slot(tx); + dma_addr_t dst = slot->dst; + dma_addr_t src = slot->src; + size_t len = slot->len; + size_t copy; + dma_cookie_t cookie; + + spin_lock_bh(&chan->lock); + + chan->tx_cmd = 0; + slot->desc_cnt = 0; + + /* Run until we are out of length */ + do { + /* Create the largest transaction possible */ + copy = min_t(size_t, len, DMA_MAX_64B_DESC_BYTE_CNT); + + /* Prepare DMA descriptor */ + xgene_dma_prep_desc(chan, slot, dst, src, copy); + + /* Update metadata */ + dst += copy; + src += copy; + len -= copy; + } while (len); + + cookie = dma_cookie_assign(tx); + + dev_dbg(chan->pdma->dev, + "Channel %d issuing op cmd %d Tx ring id 0x%X Rx ring id 0x%X\n", + chan->index, chan->tx_cmd, chan->tx_ring.id, chan->rx_ring.id); + + iowrite32(chan->tx_cmd, chan->tx_ring.cmd); + + spin_unlock_bh(&chan->lock); + + return cookie; +} + +static struct dma_async_tx_descriptor *xgene_dma_prep_memcpy( + struct dma_chan *channel, dma_addr_t dst, dma_addr_t src, + size_t len, unsigned long flags) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(channel); + struct xgene_dma_slot *slot; + + /* Sanity check */ + BUG_ON(len > DMA_MAX_MEMCPY_BYTE_CNT); + + spin_lock_bh(&chan->lock); + + slot = xgene_dma_get_channel_slot(chan); + if (!slot) { + spin_unlock_bh(&chan->lock); + return NULL; + } + + dev_dbg(chan->pdma->dev, + "Channel %d slot %d len 0x%zX dst 0x%llX src 0x%llX\n", + chan->index, slot->index, len, dst, src); + + /* Setup slot variables */ + slot->flags = FLAG_SLOT_IN_USE; + slot->async_tx.flags = flags; + slot->async_tx.tx_submit = xgene_dma_tx_memcpy_submit; + + /* + * Due to the race in tx_submit call from the client, + * need to serialize the submission of H/W DMA descriptors. + * So make shadow copy to prepare DMA descriptor during + * tx_submit call. + */ + slot->dst = dst; + slot->src = src; + slot->len = len; + + spin_unlock_bh(&chan->lock); + + return &slot->async_tx; +} + +static dma_cookie_t xgene_dma_tx_sgcpy_submit( + struct dma_async_tx_descriptor *tx) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(tx->chan); + struct xgene_dma_slot *slot = tx_to_xgene_dma_slot(tx); + struct scatterlist *dst_sg, *src_sg; + size_t dst_avail, src_avail; + dma_addr_t dst, src; + size_t len; + dma_cookie_t cookie; + size_t nbytes = slot->len; + + spin_lock_bh(&chan->lock); + + dst_sg = slot->srcdst_list + slot->src_nents; + src_sg = slot->srcdst_list; + + chan->tx_cmd = 0; + slot->desc_cnt = 0; + + /* Get prepared for the loop */ + dst_avail = sg_dma_len(dst_sg); + src_avail = sg_dma_len(src_sg); + + /* Run until we are out of length */ + do { + /* 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; + + /* Prepare DMA descriptor */ + xgene_dma_prep_desc(chan, slot, dst, src, len); + + /* Update metadata */ + dst_avail -= len; + src_avail -= len; + nbytes -= len; + +fetch: + /* Fetch the next dst scatterlist entry */ + if (dst_avail == 0 && nbytes > 0) { + dst_sg = sg_next(dst_sg); + BUG_ON(!dst_sg); + dst_avail = sg_dma_len(dst_sg); + } + + /* Fetch the next src scatterlist entry */ + if (src_avail == 0 && nbytes > 0) { + src_sg = sg_next(src_sg); + BUG_ON(!src_sg); + src_avail = sg_dma_len(src_sg); + } + } while (nbytes > 0); + + cookie = dma_cookie_assign(tx); + + dev_dbg(chan->pdma->dev, + "Channel %d issuing op cmd %d Tx ring id 0x%X Rx ring id 0x%X\n", + chan->index, chan->tx_cmd, chan->tx_ring.id, chan->rx_ring.id); + + iowrite32(chan->tx_cmd, chan->tx_ring.cmd); + + spin_unlock_bh(&chan->lock); + + return cookie; +} + +static struct dma_async_tx_descriptor *xgene_dma_prep_sg( + struct dma_chan *channel, struct scatterlist *dst_sg, + u32 dst_nents, struct scatterlist *src_sg, u32 src_nents, + unsigned long flags) +{ + struct xgene_dma_chan *chan = to_xgene_dma_chan(channel); + struct xgene_dma_slot *slot; + struct scatterlist *srcdst_list, *sg; + u32 dst_len = 0; + u32 src_len = 0; + int i; + + /* Sanity checks */ + BUG_ON(dst_nents == 0 || src_nents == 0); + BUG_ON(!dst_sg || !src_sg); + + for_each_sg(dst_sg, sg, dst_nents, i) + dst_len += sg_dma_len(sg); + + for_each_sg(src_sg, sg, src_nents, i) + src_len += sg_dma_len(sg); + + BUG_ON(dst_len != src_len); + BUG_ON(dst_len > DMA_MAX_SG_BYTE_CNT); + + srcdst_list = devm_kzalloc(chan->pdma->dev, + sizeof(struct scatterlist) * + (dst_nents + src_nents), + GFP_KERNEL); + if (!srcdst_list) { + dev_err(chan->pdma->dev, + "Channel %d failed to allocate memory for srcdst_list\n", + chan->index); + return NULL; + } + + spin_lock_bh(&chan->lock); + + slot = xgene_dma_get_channel_slot(chan); + if (!slot) { + spin_unlock_bh(&chan->lock); + devm_kfree(chan->pdma->dev, srcdst_list); + return NULL; + } + + dev_dbg(chan->pdma->dev, + "Channel %d slot %d dst_nents %d src_nents %d len 0x%X\n", + chan->index, slot->index, dst_nents, src_nents, dst_len); + + /* Setup slot variables */ + slot->flags = FLAG_SLOT_IN_USE | FLAG_SG_ACTIVE; + slot->async_tx.flags = flags; + slot->async_tx.tx_submit = xgene_dma_tx_sgcpy_submit; + + /* + * Due to the race in tx_submit call from the client, + * need to serialize the submission of H/W DMA descriptors. + * So make shadow copy to prepare DMA descriptor during + * tx_submit call. + */ + memcpy(srcdst_list, src_sg, + src_nents * sizeof(struct scatterlist)); + memcpy(srcdst_list + src_nents, dst_sg, + dst_nents * sizeof(struct scatterlist)); + slot->srcdst_list = srcdst_list; + slot->src_nents = src_nents; + slot->len = dst_len; + + spin_unlock_bh(&chan->lock); + + return &slot->async_tx; +} + +static void xgene_dma_channels_init(struct xgene_dma *pdma) +{ + struct xgene_dma_chan *chan; + int i; + + pdma->ring_num = START_DMA_RING_NUM; + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->channels[i]; + chan->pdma = pdma; + chan->index = i; + chan->slots = NULL; + spin_lock_init(&chan->lock); + tasklet_init(&chan->rx_tasklet, xgene_dma_tasklet_cb, + (unsigned long)chan); + } +} + +static int xgene_dma_async_init(struct xgene_dma *pdma) +{ + struct dma_device *dma_dev = &pdma->dma_dev; + struct xgene_dma_chan *chan; + int i, ret; + + /* Initialize DMA device list head */ + INIT_LIST_HEAD(&dma_dev->channels); + + /* 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); + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->channels[i]; + chan->dma_chan.device = dma_dev; + list_add_tail(&chan->dma_chan.device_node, &dma_dev->channels); + sprintf(chan->name, "DMA%d", chan->index); + + ret = devm_request_irq(chan->pdma->dev, chan->rx_irq, + xgene_dma_ring_isr, 0, chan->name, chan); + if (ret) { + dev_err(chan->pdma->dev, + "Channel %d failed to register Rx IRQ %d\n", + chan->index, chan->rx_irq); + return ret; + } + } + + /* Set base and prep routines */ + dma_dev->dev = chan->pdma->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; + + if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) + dma_dev->device_prep_dma_memcpy = xgene_dma_prep_memcpy; + + if (dma_has_cap(DMA_SG, dma_dev->cap_mask)) + dma_dev->device_prep_dma_sg = xgene_dma_prep_sg; + + /* Register with Linux async DMA framework*/ + ret = dma_async_device_register(dma_dev); + if (ret) { + dev_err(pdma->dev, + "Failed to register async DMA %d", ret); + return ret; + } + + /* DMA capability info */ + dev_info(pdma->dev, "CAPABILITY (%s, %s)\n", + dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? + "MEMCPY" : "", dma_has_cap(DMA_SG, dma_dev->cap_mask) ? + "Scatter/Gather" : ""); + + return 0; +} + +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 DMA 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 DMA 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 DMA 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 DMA 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"); + if (!res) { + dev_err(&pdev->dev, "Failed to get DMA 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 DMA 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 DMA Error IRQ\n"); + return -ENXIO; + } + pdma->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, + "Channel %d Failed to get DMA Rx IRQ\n", + (i - 1)); + return -ENXIO; + } + pdma->channels[i - 1].rx_irq = irq; + } + + return 0; +} + +static int xgene_dma_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xgene_dma *pdma = platform_get_drvdata(pdev); + + clk_disable_unprepare(pdma->dma_clk); + + return 0; +} + +static int xgene_dma_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xgene_dma *pdma = platform_get_drvdata(pdev); + int ret; + + ret = clk_prepare_enable(pdma->dma_clk); + if (ret) { + dev_err(dev, "Failed to enable clk %d\n", ret); + return ret; + } + + return 0; +} + +static int xgene_dma_probe(struct platform_device *pdev) +{ + struct xgene_dma *pdma; + int ret; + + /* Allocate memory to DMA device */ + pdma = devm_kzalloc(&pdev->dev, sizeof(*pdma), GFP_KERNEL); + if (!pdma) + return -ENOMEM; + + pdma->dev = &pdev->dev; + platform_set_drvdata(pdev, pdma); + + /* Get all DMA device resources */ + ret = xgene_dma_get_resources(pdev, pdma); + if (ret) + return ret; + + /* Get DMA clk */ + pdma->dma_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pdma->dma_clk)) { + dev_err(&pdev->dev, "Failed to get DMA clk\n"); + return PTR_ERR(pdma->dma_clk); + } + + /* Setup runtime resume and suspend */ + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = xgene_dma_runtime_resume(&pdev->dev); + if (ret) { + dev_err(&pdev->dev, + "Failed to resume at runtime %d\n", ret); + goto err_rt_resume; + } + } + + /* Enable clk before accessing registers */ + ret = clk_prepare_enable(pdma->dma_clk); + if (ret) { + dev_err(&pdev->dev, "Failed to enable clk %d\n", ret); + goto err_pm_enable; + } + + /* Remove DMA RAM out of shutdown */ + ret = xgene_dma_init_mem(pdma); + if (ret) + goto err_pm_enable; + + /* Register IRQ for DMA error */ + ret = devm_request_irq(&pdev->dev, pdma->irq, xgene_dma_err_isr, + 0, "DMA", pdma); + if (ret) { + dev_err(&pdev->dev, + "Failed to register DMA error IRQ %d\n", pdma->irq); + goto err_pm_enable; + } + + /* Set DMA mask and coherent mask */ + ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (ret) { + dev_err(&pdev->dev, "Failed to set DMA mask\n"); + goto err_pm_enable; + } + + /* Initialize DMA channels software state */ + xgene_dma_channels_init(pdma); + + /* Configue DMA ring descriptors */ + ret = xgene_dma_init_rings(pdma); + if (ret) + goto err_pm_enable; + + /* Register DMA device with linux async framework */ + ret = xgene_dma_async_init(pdma); + if (ret) + goto err_pm_enable; + + /* Configure and enable DMA engine */ + xgene_dma_init_hw(pdma); + + return 0; + +err_pm_enable: + if (!pm_runtime_status_suspended(&pdev->dev)) + xgene_dma_runtime_suspend(&pdev->dev); + +err_rt_resume: + pm_runtime_disable(&pdev->dev); + + 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; + + for (i = 0; i < DMA_MAX_CHANNEL; i++) { + chan = &pdma->channels[i]; + + /* Delete DMA ring descriptors */ + xgene_dma_delete_chan_rings(chan); + + /* Kill the DMA channel tasklet */ + tasklet_kill(&chan->rx_tasklet); + } + + /* Unregister DMA device */ + dma_async_device_unregister(&pdma->dma_dev); + + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + xgene_dma_runtime_suspend(&pdev->dev); + + 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 const struct dev_pm_ops xgene_dma_pm_ops = { +#ifdef CONFIG_PM_RUNTIME + .runtime_suspend = xgene_dma_runtime_suspend, + .runtime_resume = xgene_dma_runtime_resume, +#endif +}; + +static struct platform_driver xgene_dma_driver = { + .probe = xgene_dma_probe, + .remove = xgene_dma_remove, + .driver = { + .name = "X-Gene-DMA", + .owner = THIS_MODULE, + .pm = &xgene_dma_pm_ops, + .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 devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
