[PATCH v6 1/3] dmaengine: Add support for APM X-Gene SoC DMA engine driver
Rameshwar Sahu
rsahu at apm.com
Thu Feb 26 04:31:30 PST 2015
Hi Vinod,
On Tue, Feb 24, 2015 at 6:23 PM, Rameshwar Prasad Sahu <rsahu at apm.com> wrote:
> 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 at apm.com>
> Signed-off-by: Loc Ho <lho at apm.com>
> ---
> 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 at apm.com>
> + * Loc Ho <lho at apm.com>
> + *
> + * 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 at apm.com>");
> +MODULE_AUTHOR("Loc Ho <lho at apm.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION("1.0");
> --
> 1.8.2.1
>
any comments on above patch.
Thanks,
with regards,
Ram
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