[PATCH v2 1/3] dmaengine: Add support for APM X-Gene SoC DMA engine driver

Rameshwar Prasad Sahu
2015-01-07T11:09:39Z

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 gathering offload.

Signed-off-by: Rameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: Loc Ho <lho@apm.com>
---
drivers/dma/Kconfig | 8 +
drivers/dma/Makefile | 1 +
drivers/dma/xgene-dma.c | 1500 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1509 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..ba8001a
--- /dev/null
+++ b/drivers/dma/xgene-dma.c
@@ -0,0 +1,1500 @@
+/* Applied Micro X-Gene SoC DMA engine Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Authors: Rameshwar Prasad Sahu <rsahu@apm.com>
+ * Loc Ho <lho@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/>.
+ */
+
+#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)
+{
+ dev_dbg(pdma->dev, "Release memory from shutdown\n");
+ writel(0x0, pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN);
+
+ /* Force a barrier */
+ readl(pdma->csr_dma + DMA_MEM_RAM_SHUTDOWN);
+
+ /* reset may take up to 1ms */
+ usleep_range(500, 1000);
+
+ if (readl(pdma->csr_dma + DMA_BLK_MEM_RDY)
+ != DMA_BLK_MEM_RDY_DEFAULT) {
+ 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;
+ }
+
+ dma_set_mask_and_coherent(&pdev->dev,
+ (sizeof(dma_addr_t) == sizeof(u64)) ?
+ DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
+
+ /* 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@apm.com>");
+MODULE_AUTHOR("Loc Ho <lho@apm.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0");
--
1.8.2.1