Add ZTE ZX296702 dma controller support. Only
device tree probe is support currently.
Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
Reviewed-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/dma/Kconfig | 7 +
drivers/dma/Makefile | 1 +
drivers/dma/zx296702_dma.c | 870 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 878 insertions(+)
create mode 100644 drivers/dma/zx296702_dma.c
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index fd7ac13..d8fab64 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -442,6 +442,13 @@ config XGENE_DMA
select ASYNC_TX_ENABLE_CHANNEL_SWITCH
help
Enable support for the APM X-Gene SoC DMA engine.
+config ZX_DMA
+ tristate "ZTE ZX296702 DMA support"
+ depends on ARCH_ZX
+ select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
+ help
+ Support the DMA engine for ZTE ZX296702 platform devices.
config DMA_ENGINE
bool
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 69f77d5..b2580e8 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -54,3 +54,4 @@ 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
+obj-$(CONFIG_ZX_DMA) += zx296702_dma.o
diff --git a/drivers/dma/zx296702_dma.c b/drivers/dma/zx296702_dma.c
new file mode 100644
index 0000000..c99f0d1
--- /dev/null
+++ b/drivers/dma/zx296702_dma.c
@@ -0,0 +1,870 @@
+/*
+ * Copyright 2015 Linaro.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/sched.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+#include <linux/of_dma.h>
+
+#include "virt-dma.h"
+
+#define DRIVER_NAME "zx-dma"
+#define DMA_ALIGN 4
+#define DMA_MAX_SIZE (0x10000 - PAGE_SIZE)
+#define LLI_BLOCK_SIZE (4 * PAGE_SIZE)
+
+#define REG_ZX_SRC_ADDR 0x00
+#define REG_ZX_DST_ADDR 0x04
+#define REG_ZX_TX_X_COUNT 0x08
+#define REG_ZX_TX_ZY_COUNT 0x0c
+#define REG_ZX_SRC_ZY_STEP 0x10
+#define REG_ZX_DST_ZY_STEP 0x14
+#define REG_ZX_LLI_ADDR 0x1c
+#define REG_ZX_CTRL 0x20
+#define REG_ZX_TC_IRQ 0x800
+#define REG_ZX_SRC_ERR_IRQ 0x804
+#define REG_ZX_DST_ERR_IRQ 0x808
+#define REG_ZX_CFG_ERR_IRQ 0x80c
+#define REG_ZX_TC_IRQ_RAW 0x810
+#define REG_ZX_SRC_ERR_IRQ_RAW 0x814
+#define REG_ZX_DST_ERR_IRQ_RAW 0x818
+#define REG_ZX_CFG_ERR_IRQ_RAW 0x81c
+#define REG_ZX_STATUS 0x820
+#define REG_ZX_DMA_GRP_PRIO 0x824
+#define REG_ZX_DMA_ARB 0x828
+
+#define ZX_FORCE_CLOSE BIT(31)
+#define ZX_DST_BURST_WIDTH(x) (((x) & 0x7) << 13)
+#define ZX_MAX_BURST_LEN 16
+#define ZX_SRC_BURST_LEN(x) (((x) & 0xf) << 9)
+#define ZX_SRC_BURST_WIDTH(x) (((x) & 0x7) << 6)
+#define ZX_IRQ_ENABLE_ALL (3 << 4)
+#define ZX_DST_FIFO_MODE BIT(3)
+#define ZX_SRC_FIFO_MODE BIT(2)
+#define ZX_SOFT_REQ BIT(1)
+#define ZX_CH_ENABLE BIT(0)
+
+#define ZX_DMA_BUSWIDTHS \
+ (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
+ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
+
+enum zx_dma_burst_width {
+ ZX_DMA_WIDTH_8BIT = 0,
+ ZX_DMA_WIDTH_16BIT = 1,
+ ZX_DMA_WIDTH_32BIT = 2,
+ ZX_DMA_WIDTH_64BIT = 3,
+};
+
+struct zx_desc_hw {
+ u32 saddr;
+ u32 daddr;
+ u32 src_x;
+ u32 src_zy;
+ u32 src_zy_step;
+ u32 dst_zy_step;
+ u32 reserved1;
+ u32 lli;
+ u32 ctr;
+ u32 reserved[7]; /* pack as hardware registers region size */
+} __aligned(32);
+
+struct zx_dma_desc_sw {
+ struct virt_dma_desc vd;
+ dma_addr_t desc_hw_lli;
+ size_t desc_num;
+ size_t size;
+ struct zx_desc_hw *desc_hw;
+};
+
+struct zx_dma_phy;
+
+struct zx_dma_chan {
+ struct dma_slave_config slave_cfg;
+ int id; /* Request phy chan id */
+ u32 ccfg;
+ struct virt_dma_chan vc;
+ struct zx_dma_phy *phy;
+ struct list_head node;
+ dma_addr_t dev_addr;
+ enum dma_status status;
+};
+
+struct zx_dma_phy {
+ u32 idx;
+ void __iomem *base;
+ struct zx_dma_chan *vchan;
+ struct zx_dma_desc_sw *ds_run;
+ struct zx_dma_desc_sw *ds_done;
+};
+
+struct zx_dma_dev {
+ struct dma_device slave;
+ void __iomem *base;
+ spinlock_t lock; /* lock for ch and phy */
+ struct list_head chan_pending;
+ struct zx_dma_phy *phy;
+ struct zx_dma_chan *chans;
+ struct clk *clk;
+ struct dma_pool *pool;
+ u32 dma_channels;
+ u32 dma_requests;
+};
+
+#define to_zx_dma(dmadev) container_of(dmadev, struct zx_dma_dev, slave)
+
+static struct zx_dma_chan *to_zx_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct zx_dma_chan, vc.chan);
+}
+
+static void zx_dma_terminate_chan(struct zx_dma_phy *phy, struct zx_dma_dev *d)
+{
+ u32 val = 0;
+
+ val = readl_relaxed(phy->base + REG_ZX_CTRL);
+ val &= ~ZX_CH_ENABLE;
+ writel_relaxed(val, phy->base + REG_ZX_CTRL);
+
+ val = 0x1 << phy->idx;
+ writel_relaxed(val, d->base + REG_ZX_TC_IRQ_RAW);
+ writel_relaxed(val, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
+ writel_relaxed(val, d->base + REG_ZX_DST_ERR_IRQ_RAW);
+ writel_relaxed(val, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
+}
+
+static void zx_dma_set_desc(struct zx_dma_phy *phy, struct zx_desc_hw *hw)
+{
+ writel_relaxed(hw->saddr, phy->base + REG_ZX_SRC_ADDR);
+ writel_relaxed(hw->daddr, phy->base + REG_ZX_DST_ADDR);
+ writel_relaxed(hw->src_x, phy->base + REG_ZX_TX_X_COUNT);
+ writel_relaxed(0, phy->base + REG_ZX_TX_ZY_COUNT);
+ writel_relaxed(0, phy->base + REG_ZX_SRC_ZY_STEP);
+ writel_relaxed(0, phy->base + REG_ZX_DST_ZY_STEP);
+ writel_relaxed(hw->lli, phy->base + REG_ZX_LLI_ADDR);
+ writel_relaxed(hw->ctr, phy->base + REG_ZX_CTRL);
+}
+
+static u32 zx_dma_get_curr_lli(struct zx_dma_phy *phy)
+{
+ return readl_relaxed(phy->base + REG_ZX_LLI_ADDR);
+}
+
+static u32 zx_dma_get_chan_stat(struct zx_dma_dev *d)
+{
+ return readl_relaxed(d->base + REG_ZX_STATUS);
+}
+
+static void zx_dma_init_state(struct zx_dma_dev *d)
+{
+ /* set same priority */
+ writel_relaxed(0x0, d->base + REG_ZX_DMA_ARB);
+ /* clear all irq */
+ writel_relaxed(0xffffffff, d->base + REG_ZX_TC_IRQ_RAW);
+ writel_relaxed(0xffffffff, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
+ writel_relaxed(0xffffffff, d->base + REG_ZX_DST_ERR_IRQ_RAW);
+ writel_relaxed(0xffffffff, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
+}
+
+static int zx_dma_start_txd(struct zx_dma_chan *c)
+{
+ struct zx_dma_dev *d = to_zx_dma(c->vc.chan.device);
+ struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
+
+ if (!c->phy)
+ return -EAGAIN;
+
+ if (BIT(c->phy->idx) & zx_dma_get_chan_stat(d))
+ return -EAGAIN;
+
+ if (vd) {
+ struct zx_dma_desc_sw *ds =
+ container_of(vd, struct zx_dma_desc_sw, vd);
+ /*
+ * fetch and remove request from vc->desc_issued
+ * so vc->desc_issued only contains desc pending
+ */
+ list_del(&ds->vd.node);
+ c->phy->ds_run = ds;
+ c->phy->ds_done = NULL;
+ /* start dma */
+ zx_dma_set_desc(c->phy, ds->desc_hw);
+ return 0;
+ }
+ c->phy->ds_done = NULL;
+ c->phy->ds_run = NULL;
+ return -EAGAIN;
+}
+
+static void zx_dma_task(struct zx_dma_dev *d)
+{
+ struct zx_dma_phy *p;
+ struct zx_dma_chan *c, *cn;
+ unsigned pch, pch_alloc = 0;
+ unsigned long flags;
+
+ /* check new dma request of running channel in vc->desc_issued */
+ list_for_each_entry_safe(c, cn, &d->slave.channels,
+ vc.chan.device_node) {
+ spin_lock_irqsave(&c->vc.lock, flags);
+ p = c->phy;
+ if (p && p->ds_done && zx_dma_start_txd(c)) {
+ /* No current txd associated with this channel */
+ dev_dbg(d->slave.dev, "pchan %u: free\n", p->idx);
+ /* Mark this channel free */
+ c->phy = NULL;
+ p->vchan = NULL;
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+ }
+
+ /* check new channel request in d->chan_pending */
+ spin_lock_irqsave(&d->lock, flags);
+ while (!list_empty(&d->chan_pending)) {
+ c = list_first_entry(&d->chan_pending,
+ struct zx_dma_chan, node);
+ p = &d->phy[c->id];
+ if (!p->vchan) {
+ /* remove from d->chan_pending */
+ list_del_init(&c->node);
+ pch_alloc |= 1 << c->id;
+ /* Mark this channel allocated */
+ p->vchan = c;
+ c->phy = p;
+ } else {
+ dev_dbg(d->slave.dev, "pchan %u: busy!\n", c->id);
+ }
+ }
+ spin_unlock_irqrestore(&d->lock, flags);
+
+ for (pch = 0; pch < d->dma_channels; pch++) {
+ if (pch_alloc & (1 << pch)) {
+ p = &d->phy[pch];
+ c = p->vchan;
+ if (c) {
+ spin_lock_irqsave(&c->vc.lock, flags);
+ zx_dma_start_txd(c);
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+ }
+ }
+ }
+}
+
+static irqreturn_t zx_dma_int_handler(int irq, void *dev_id)
+{
+ struct zx_dma_dev *d = (struct zx_dma_dev *)dev_id;
+ struct zx_dma_phy *p;
+ struct zx_dma_chan *c;
+ u32 tc = readl_relaxed(d->base + REG_ZX_TC_IRQ);
+ u32 serr = readl_relaxed(d->base + REG_ZX_SRC_ERR_IRQ);
+ u32 derr = readl_relaxed(d->base + REG_ZX_DST_ERR_IRQ);
+ u32 cfg = readl_relaxed(d->base + REG_ZX_CFG_ERR_IRQ);
+ u32 i, irq_chan = 0;
+
+ while (tc) {
+ i = __ffs(tc);
+ tc &= ~BIT(i);
+ p = &d->phy[i];
+ c = p->vchan;
+ if (c) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+ vchan_cookie_complete(&p->ds_run->vd);
+ p->ds_done = p->ds_run;
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+ }
+ irq_chan |= BIT(i);
+ }
+
+ if (serr || derr || cfg)
+ dev_warn(d->slave.dev, "DMA ERR src 0x%x, dst 0x%x, cfg 0x%x\n",
+ serr, derr, cfg);
+
+ writel_relaxed(irq_chan, d->base + REG_ZX_TC_IRQ_RAW);
+ writel_relaxed(serr, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
+ writel_relaxed(derr, d->base + REG_ZX_DST_ERR_IRQ_RAW);
+ writel_relaxed(cfg, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
+
+ if (irq_chan) {
+ zx_dma_task(d);
+ return IRQ_HANDLED;
+ } else {
+ return IRQ_NONE;
+ }
+}
+
+static void zx_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_dev *d = to_zx_dma(chan->device);
+ unsigned long flags;
+
+ spin_lock_irqsave(&d->lock, flags);
+ list_del_init(&c->node);
+ spin_unlock_irqrestore(&d->lock, flags);
+
+ vchan_free_chan_resources(&c->vc);
+ c->ccfg = 0;
+}
+
+static enum dma_status zx_dma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *state)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_phy *p;
+ struct virt_dma_desc *vd;
+ unsigned long flags;
+ enum dma_status ret;
+ size_t bytes = 0;
+
+ ret = dma_cookie_status(&c->vc.chan, cookie, state);
+ if (ret == DMA_COMPLETE || !state)
+ return ret;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+ p = c->phy;
+ ret = c->status;
+
+ /*
+ * If the cookie is on our issue queue, then the residue is
+ * its total size.
+ */
+ vd = vchan_find_desc(&c->vc, cookie);
+ if (vd) {
+ bytes = container_of(vd, struct zx_dma_desc_sw, vd)->size;
+ } else if ((!p) || (!p->ds_run)) {
+ bytes = 0;
+ } else {
+ struct zx_dma_desc_sw *ds = p->ds_run;
+ u32 clli = 0, index = 0;
+
+ bytes = 0;
+ clli = zx_dma_get_curr_lli(p);
+ index = (clli - ds->desc_hw_lli) / sizeof(struct zx_desc_hw);
+ for (; index < ds->desc_num; index++) {
+ bytes += ds->desc_hw[index].src_x;
+ /* end of lli */
+ if (!ds->desc_hw[index].lli)
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+ dma_set_residue(state, bytes);
+ return ret;
+}
+
+static void zx_dma_issue_pending(struct dma_chan *chan)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_dev *d = to_zx_dma(chan->device);
+ unsigned long flags;
+ int issue = 0;
+
+ spin_lock_irqsave(&c->vc.lock, flags);
+ /* add request to vc->desc_issued */
+ if (vchan_issue_pending(&c->vc)) {
+ spin_lock(&d->lock);
+ if (!c->phy && list_empty(&c->node)) {
+ /* if new channel, add chan_pending */
+ list_add_tail(&c->node, &d->chan_pending);
+ issue = 1;
+ dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc);
+ }
+ spin_unlock(&d->lock);
+ } else {
+ dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc);
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+
+ if (issue)
+ zx_dma_task(d);
+}
+
+static void zx_dma_fill_desc(struct zx_dma_desc_sw *ds, dma_addr_t dst,
+ dma_addr_t src, size_t len, u32 num, u32 ccfg)
+{
+ if ((num + 1) < ds->desc_num)
+ ds->desc_hw[num].lli = ds->desc_hw_lli + (num + 1) *
+ sizeof(struct zx_desc_hw);
+ ds->desc_hw[num].saddr = src;
+ ds->desc_hw[num].daddr = dst;
+ ds->desc_hw[num].src_x = len;
+ ds->desc_hw[num].ctr = ccfg;
+}
+
+static struct zx_dma_desc_sw *zx_alloc_desc_resource(int num,
+ struct dma_chan *chan)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_desc_sw *ds;
+ struct zx_dma_dev *d = to_zx_dma(chan->device);
+ int lli_limit = LLI_BLOCK_SIZE / sizeof(struct zx_desc_hw);
+
+ if (num > lli_limit) {
+ dev_dbg(chan->device->dev, "vch %p: sg num %d exceed max %d\n",
+ &c->vc, num, lli_limit);
+ return NULL;
+ }
+
+ ds = kzalloc(sizeof(*ds), GFP_ATOMIC);
+ if (!ds)
+ return NULL;
+
+ ds->desc_hw = dma_pool_alloc(d->pool, GFP_NOWAIT, &ds->desc_hw_lli);
+ if (!ds->desc_hw) {
+ dev_dbg(chan->device->dev, "vch %p: dma alloc fail\n", &c->vc);
+ kfree(ds);
+ return NULL;
+ }
+ memset(ds->desc_hw, sizeof(struct zx_desc_hw) * num, 0);
+ ds->desc_num = num;
+ return ds;
+}
+
+static enum zx_dma_burst_width zx_dma_burst_width(enum dma_slave_buswidth width)
+{
+ switch (width) {
+ case DMA_SLAVE_BUSWIDTH_1_BYTE:
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ return ffs(width) - 1;
+ default:
+ return ZX_DMA_WIDTH_32BIT;
+ }
+}
+
+static int zx_pre_config(struct zx_dma_chan *c, enum dma_transfer_direction dir)
+{
+ struct dma_slave_config *cfg = &c->slave_cfg;
+ enum zx_dma_burst_width src_width;
+ enum zx_dma_burst_width dst_width;
+ u32 maxburst = 0;
+
+ switch (dir) {
+ case DMA_MEM_TO_MEM:
+ c->ccfg = ZX_CH_ENABLE | ZX_SOFT_REQ
+ | ZX_SRC_BURST_LEN(ZX_MAX_BURST_LEN - 1)
+ | ZX_SRC_BURST_WIDTH(ZX_DMA_WIDTH_32BIT)
+ | ZX_DST_BURST_WIDTH(ZX_DMA_WIDTH_32BIT);
+ break;
+ case DMA_MEM_TO_DEV:
+ c->dev_addr = cfg->dst_addr;
+ /* dst len is calculated from src width, len and dst width.
+ * We need make sure dst len not exceed MAX LEN.
+ */
+ dst_width = zx_dma_burst_width(cfg->dst_addr_width);
+ maxburst = cfg->dst_maxburst * cfg->dst_addr_width
+ / DMA_SLAVE_BUSWIDTH_8_BYTES;
+ maxburst = maxburst < ZX_MAX_BURST_LEN ?
+ maxburst : ZX_MAX_BURST_LEN;
+ c->ccfg = ZX_DST_FIFO_MODE | ZX_CH_ENABLE
+ | ZX_SRC_BURST_LEN(maxburst - 1)
+ | ZX_SRC_BURST_WIDTH(ZX_DMA_WIDTH_64BIT)
+ | ZX_DST_BURST_WIDTH(dst_width);
+ break;
+ case DMA_DEV_TO_MEM:
+ c->dev_addr = cfg->src_addr;
+ src_width = zx_dma_burst_width(cfg->src_addr_width);
+ maxburst = cfg->src_maxburst;
+ maxburst = maxburst < ZX_MAX_BURST_LEN ?
+ maxburst : ZX_MAX_BURST_LEN;
+ c->ccfg = ZX_SRC_FIFO_MODE | ZX_CH_ENABLE
+ | ZX_SRC_BURST_LEN(maxburst - 1)
+ | ZX_SRC_BURST_WIDTH(src_width)
+ | ZX_DST_BURST_WIDTH(ZX_DMA_WIDTH_64BIT);
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct dma_async_tx_descriptor *zx_dma_prep_memcpy(
+ struct dma_chan *chan, dma_addr_t dst, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_desc_sw *ds;
+ size_t copy = 0;
+ int num = 0;
+
+ if (!len)
+ return NULL;
+
+ if (zx_pre_config(c, DMA_MEM_TO_MEM))
+ return NULL;
+
+ num = DIV_ROUND_UP(len, DMA_MAX_SIZE);
+
+ ds = zx_alloc_desc_resource(num, chan);
+ if (!ds)
+ return NULL;
+
+ ds->size = len;
+ num = 0;
+
+ do {
+ copy = min_t(size_t, len, DMA_MAX_SIZE);
+ zx_dma_fill_desc(ds, dst, src, copy, num++, c->ccfg);
+
+ src += copy;
+ dst += copy;
+ len -= copy;
+ } while (len);
+
+ ds->desc_hw[num - 1].lli = 0; /* end of link */
+ ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL;
+ return vchan_tx_prep(&c->vc, &ds->vd, flags);
+}
+
+static struct dma_async_tx_descriptor *zx_dma_prep_slave_sg(
+ struct dma_chan *chan, struct scatterlist *sgl, unsigned int sglen,
+ enum dma_transfer_direction dir, unsigned long flags, void *context)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_desc_sw *ds;
+ size_t len, avail, total = 0;
+ struct scatterlist *sg;
+ dma_addr_t addr, src = 0, dst = 0;
+ int num = sglen, i;
+
+ if (!sgl)
+ return NULL;
+
+ if (zx_pre_config(c, dir))
+ return NULL;
+
+ for_each_sg(sgl, sg, sglen, i) {
+ avail = sg_dma_len(sg);
+ if (avail > DMA_MAX_SIZE)
+ num += DIV_ROUND_UP(avail, DMA_MAX_SIZE) - 1;
+ }
+
+ ds = zx_alloc_desc_resource(num, chan);
+ if (!ds)
+ return NULL;
+
+ num = 0;
+ for_each_sg(sgl, sg, sglen, i) {
+ addr = sg_dma_address(sg);
+ avail = sg_dma_len(sg);
+ total += avail;
+
+ do {
+ len = min_t(size_t, avail, DMA_MAX_SIZE);
+
+ if (dir == DMA_MEM_TO_DEV) {
+ src = addr;
+ dst = c->dev_addr;
+ } else if (dir == DMA_DEV_TO_MEM) {
+ src = c->dev_addr;
+ dst = addr;
+ }
+
+ zx_dma_fill_desc(ds, dst, src, len, num++, c->ccfg);
+
+ addr += len;
+ avail -= len;
+ } while (avail);
+ }
+
+ ds->desc_hw[num - 1].lli = 0; /* end of link */
+ ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL;
+ ds->size = total;
+ return vchan_tx_prep(&c->vc, &ds->vd, flags);
+}
+
+static int zx_dma_config(struct dma_chan *chan,
+ struct dma_slave_config *cfg)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+
+ if (!cfg)
+ return -EINVAL;
+
+ memcpy(&c->slave_cfg, cfg, sizeof(*cfg));
+
+ return 0;
+}
+
+static int zx_dma_terminate_all(struct dma_chan *chan)
+{
+ struct zx_dma_chan *c = to_zx_chan(chan);
+ struct zx_dma_dev *d = to_zx_dma(chan->device);
+ struct zx_dma_phy *p = c->phy;
+ unsigned long flags;
+ LIST_HEAD(head);
+
+ dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc);
+
+ /* Prevent this channel being scheduled */
+ spin_lock(&d->lock);
+ list_del_init(&c->node);
+ spin_unlock(&d->lock);
+
+ /* Clear the tx descriptor lists */
+ spin_lock_irqsave(&c->vc.lock, flags);
+ vchan_get_all_descriptors(&c->vc, &head);
+ if (p) {
+ /* vchan is assigned to a pchan - stop the channel */
+ zx_dma_terminate_chan(p, d);
+ c->phy = NULL;
+ p->vchan = NULL;
+ p->ds_run = NULL;
+ p->ds_done = NULL;
+ }
+ spin_unlock_irqrestore(&c->vc.lock, flags);
+ vchan_dma_desc_free_list(&c->vc, &head);
+
+ return 0;
+}
+
+static void zx_dma_free_desc(struct virt_dma_desc *vd)
+{
+ struct zx_dma_desc_sw *ds =
+ container_of(vd, struct zx_dma_desc_sw, vd);
+ struct zx_dma_dev *d = to_zx_dma(vd->tx.chan->device);
+
+ dma_pool_free(d->pool, ds->desc_hw, ds->desc_hw_lli);
+ kfree(ds);
+}
+
+static const struct of_device_id zx6702_dma_dt_ids[] = {
+ { .compatible = "zte,zx296702-dma", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, zx6702_dma_dt_ids);
+
+static struct dma_chan *zx_of_dma_simple_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct zx_dma_dev *d = ofdma->of_dma_data;
+ unsigned int request = dma_spec->args[0];
+ struct dma_chan *chan;
+ struct zx_dma_chan *c;
+
+ if (request > d->dma_requests)
+ return NULL;
+
+ chan = dma_get_any_slave_channel(&d->slave);
+ if (!chan) {
+ dev_err(d->slave.dev, "get channel fail in %s.\n", __func__);
+ return NULL;
+ }
+ c = to_zx_chan(chan);
+ c->id = request;
+ dev_info(d->slave.dev, "zx_dma: pchan %u: alloc vchan %p\n",
+ c->id, &c->vc);
+ return chan;
+}
+
+static int zx_dma_probe(struct platform_device *op)
+{
+ struct zx_dma_dev *d;
+ struct resource *iores;
+ int i, ret = 0, irq = 0;
+
+ iores = platform_get_resource(op, IORESOURCE_MEM, 0);
+ if (!iores)
+ return -EINVAL;
+
+ d = devm_kzalloc(&op->dev, sizeof(*d), GFP_KERNEL);
+ if (!d)
+ return -ENOMEM;
+
+ d->base = devm_ioremap_resource(&op->dev, iores);
+ if (IS_ERR(d->base))
+ return PTR_ERR(d->base);
+
+ of_property_read_u32((&op->dev)->of_node,
+ "dma-channels", &d->dma_channels);
+ of_property_read_u32((&op->dev)->of_node,
+ "dma-requests", &d->dma_requests);
+ if (!d->dma_requests || !d->dma_channels)
+ return -EINVAL;
+
+ d->clk = devm_clk_get(&op->dev, NULL);
+ if (IS_ERR(d->clk)) {
+ dev_err(&op->dev, "no dma clk\n");
+ return PTR_ERR(d->clk);
+ }
+
+ irq = platform_get_irq(op, 0);
+ ret = devm_request_irq(&op->dev, irq, zx_dma_int_handler,
+ 0, DRIVER_NAME, d);
+ if (ret)
+ return ret;
+
+ /* A DMA memory pool for LLIs, align on 32-byte boundary */
+ d->pool = dmam_pool_create(DRIVER_NAME, &op->dev,
+ LLI_BLOCK_SIZE, 32, 0);
+ if (!d->pool)
+ return -ENOMEM;
+
+ /* init phy channel */
+ d->phy = devm_kzalloc(&op->dev,
+ d->dma_channels * sizeof(struct zx_dma_phy), GFP_KERNEL);
+ if (!d->phy)
+ return -ENOMEM;
+
+ for (i = 0; i < d->dma_channels; i++) {
+ struct zx_dma_phy *p = &d->phy[i];
+
+ p->idx = i;
+ p->base = d->base + i * 0x40;
+ }
+
+ INIT_LIST_HEAD(&d->slave.channels);
+ dma_cap_set(DMA_SLAVE, d->slave.cap_mask);
+ dma_cap_set(DMA_MEMCPY, d->slave.cap_mask);
+ dma_cap_set(DMA_PRIVATE, d->slave.cap_mask);
+ d->slave.dev = &op->dev;
+ d->slave.device_free_chan_resources = zx_dma_free_chan_resources;
+ d->slave.device_tx_status = zx_dma_tx_status;
+ d->slave.device_prep_dma_memcpy = zx_dma_prep_memcpy;
+ d->slave.device_prep_slave_sg = zx_dma_prep_slave_sg;
+ d->slave.device_issue_pending = zx_dma_issue_pending;
+ d->slave.device_config = zx_dma_config;
+ d->slave.device_terminate_all = zx_dma_terminate_all;
+ d->slave.copy_align = DMA_ALIGN;
+ d->slave.src_addr_widths = ZX_DMA_BUSWIDTHS;
+ d->slave.dst_addr_widths = ZX_DMA_BUSWIDTHS;
+ d->slave.directions = BIT(DMA_MEM_TO_MEM) | BIT(DMA_MEM_TO_DEV)
+ | BIT(DMA_DEV_TO_MEM);
+ d->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
+
+ /* init virtual channel */
+ d->chans = devm_kzalloc(&op->dev,
+ d->dma_requests * sizeof(struct zx_dma_chan), GFP_KERNEL);
+ if (!d->chans)
+ return -ENOMEM;
+
+ for (i = 0; i < d->dma_requests; i++) {
+ struct zx_dma_chan *c = &d->chans[i];
+
+ c->status = DMA_IN_PROGRESS;
+ INIT_LIST_HEAD(&c->node);
+ c->vc.desc_free = zx_dma_free_desc;
+ vchan_init(&c->vc, &d->slave);
+ }
+
+ /* Enable clock before accessing registers */
+ ret = clk_prepare_enable(d->clk);
+ if (ret < 0) {
+ dev_err(&op->dev, "clk_prepare_enable failed: %d\n", ret);
+ goto zx_dma_out;
+ }
+
+ zx_dma_init_state(d);
+
+ spin_lock_init(&d->lock);
+ INIT_LIST_HEAD(&d->chan_pending);
+ platform_set_drvdata(op, d);
+
+ ret = dma_async_device_register(&d->slave);
+ if (ret)
+ goto clk_dis;
+
+ ret = of_dma_controller_register((&op->dev)->of_node,
+ zx_of_dma_simple_xlate, d);
+ if (ret)
+ goto of_dma_register_fail;
+
+ dev_info(&op->dev, "initialized\n");
+ return 0;
+
+of_dma_register_fail:
+ dma_async_device_unregister(&d->slave);
+clk_dis:
+ clk_disable_unprepare(d->clk);
+zx_dma_out:
+ return ret;
+}
+
+static int zx_dma_remove(struct platform_device *op)
+{
+ struct zx_dma_chan *c, *cn;
+ struct zx_dma_dev *d = platform_get_drvdata(op);
+
+ dma_async_device_unregister(&d->slave);
+ of_dma_controller_free((&op->dev)->of_node);
+
+ list_for_each_entry_safe(c, cn, &d->slave.channels,
+ vc.chan.device_node) {
+ list_del(&c->vc.chan.device_node);
+ }
+ clk_disable_unprepare(d->clk);
+ dmam_pool_destroy(d->pool);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int zx_dma_suspend_dev(struct device *dev)
+{
+ struct zx_dma_dev *d = dev_get_drvdata(dev);
+ u32 stat = 0;
+
+ stat = zx_dma_get_chan_stat(d);
+ if (stat) {
+ dev_warn(d->slave.dev,
+ "chan %d is running fail to suspend\n", stat);
+ return -1;
+ }
+ clk_disable_unprepare(d->clk);
+ return 0;
+}
+
+static int zx_dma_resume_dev(struct device *dev)
+{
+ struct zx_dma_dev *d = dev_get_drvdata(dev);
+ int ret = 0;
+
+ ret = clk_prepare_enable(d->clk);
+ if (ret < 0) {
+ dev_err(d->slave.dev, "clk_prepare_enable failed: %d\n", ret);
+ return ret;
+ }
+ zx_dma_init_state(d);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(zx_dma_pmops, zx_dma_suspend_dev, zx_dma_resume_dev);
+
+static struct platform_driver zx_pdma_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .pm = &zx_dma_pmops,
+ .of_match_table = zx6702_dma_dt_ids,
+ },
+ .probe = zx_dma_probe,
+ .remove = zx_dma_remove,
+};
+
+module_platform_driver(zx_pdma_driver);
+
+MODULE_DESCRIPTION("ZTE ZX296702 DMA Driver");
+MODULE_AUTHOR("Jun Nie jun.nie@xxxxxxxxxx");
+MODULE_LICENSE("GPL v2");
--
1.9.1
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