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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/dma/sirf-dma.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/dma/sirf-dma.c')
-rw-r--r--kernel/drivers/dma/sirf-dma.c931
1 files changed, 931 insertions, 0 deletions
diff --git a/kernel/drivers/dma/sirf-dma.c b/kernel/drivers/dma/sirf-dma.c
new file mode 100644
index 000000000..a1afda43b
--- /dev/null
+++ b/kernel/drivers/dma/sirf-dma.c
@@ -0,0 +1,931 @@
+/*
+ * DMA controller driver for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/pm_runtime.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/clk.h>
+#include <linux/of_dma.h>
+#include <linux/sirfsoc_dma.h>
+
+#include "dmaengine.h"
+
+#define SIRFSOC_DMA_DESCRIPTORS 16
+#define SIRFSOC_DMA_CHANNELS 16
+
+#define SIRFSOC_DMA_CH_ADDR 0x00
+#define SIRFSOC_DMA_CH_XLEN 0x04
+#define SIRFSOC_DMA_CH_YLEN 0x08
+#define SIRFSOC_DMA_CH_CTRL 0x0C
+
+#define SIRFSOC_DMA_WIDTH_0 0x100
+#define SIRFSOC_DMA_CH_VALID 0x140
+#define SIRFSOC_DMA_CH_INT 0x144
+#define SIRFSOC_DMA_INT_EN 0x148
+#define SIRFSOC_DMA_INT_EN_CLR 0x14C
+#define SIRFSOC_DMA_CH_LOOP_CTRL 0x150
+#define SIRFSOC_DMA_CH_LOOP_CTRL_CLR 0x15C
+
+#define SIRFSOC_DMA_MODE_CTRL_BIT 4
+#define SIRFSOC_DMA_DIR_CTRL_BIT 5
+
+/* xlen and dma_width register is in 4 bytes boundary */
+#define SIRFSOC_DMA_WORD_LEN 4
+
+struct sirfsoc_dma_desc {
+ struct dma_async_tx_descriptor desc;
+ struct list_head node;
+
+ /* SiRFprimaII 2D-DMA parameters */
+
+ int xlen; /* DMA xlen */
+ int ylen; /* DMA ylen */
+ int width; /* DMA width */
+ int dir;
+ bool cyclic; /* is loop DMA? */
+ u32 addr; /* DMA buffer address */
+};
+
+struct sirfsoc_dma_chan {
+ struct dma_chan chan;
+ struct list_head free;
+ struct list_head prepared;
+ struct list_head queued;
+ struct list_head active;
+ struct list_head completed;
+ unsigned long happened_cyclic;
+ unsigned long completed_cyclic;
+
+ /* Lock for this structure */
+ spinlock_t lock;
+
+ int mode;
+};
+
+struct sirfsoc_dma_regs {
+ u32 ctrl[SIRFSOC_DMA_CHANNELS];
+ u32 interrupt_en;
+};
+
+struct sirfsoc_dma {
+ struct dma_device dma;
+ struct tasklet_struct tasklet;
+ struct sirfsoc_dma_chan channels[SIRFSOC_DMA_CHANNELS];
+ void __iomem *base;
+ int irq;
+ struct clk *clk;
+ bool is_marco;
+ struct sirfsoc_dma_regs regs_save;
+};
+
+#define DRV_NAME "sirfsoc_dma"
+
+static int sirfsoc_dma_runtime_suspend(struct device *dev);
+
+/* Convert struct dma_chan to struct sirfsoc_dma_chan */
+static inline
+struct sirfsoc_dma_chan *dma_chan_to_sirfsoc_dma_chan(struct dma_chan *c)
+{
+ return container_of(c, struct sirfsoc_dma_chan, chan);
+}
+
+/* Convert struct dma_chan to struct sirfsoc_dma */
+static inline struct sirfsoc_dma *dma_chan_to_sirfsoc_dma(struct dma_chan *c)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(c);
+ return container_of(schan, struct sirfsoc_dma, channels[c->chan_id]);
+}
+
+/* Execute all queued DMA descriptors */
+static void sirfsoc_dma_execute(struct sirfsoc_dma_chan *schan)
+{
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
+ int cid = schan->chan.chan_id;
+ struct sirfsoc_dma_desc *sdesc = NULL;
+
+ /*
+ * lock has been held by functions calling this, so we don't hold
+ * lock again
+ */
+
+ sdesc = list_first_entry(&schan->queued, struct sirfsoc_dma_desc,
+ node);
+ /* Move the first queued descriptor to active list */
+ list_move_tail(&sdesc->node, &schan->active);
+
+ /* Start the DMA transfer */
+ writel_relaxed(sdesc->width, sdma->base + SIRFSOC_DMA_WIDTH_0 +
+ cid * 4);
+ writel_relaxed(cid | (schan->mode << SIRFSOC_DMA_MODE_CTRL_BIT) |
+ (sdesc->dir << SIRFSOC_DMA_DIR_CTRL_BIT),
+ sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_CTRL);
+ writel_relaxed(sdesc->xlen, sdma->base + cid * 0x10 +
+ SIRFSOC_DMA_CH_XLEN);
+ writel_relaxed(sdesc->ylen, sdma->base + cid * 0x10 +
+ SIRFSOC_DMA_CH_YLEN);
+ writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) |
+ (1 << cid), sdma->base + SIRFSOC_DMA_INT_EN);
+
+ /*
+ * writel has an implict memory write barrier to make sure data is
+ * flushed into memory before starting DMA
+ */
+ writel(sdesc->addr >> 2, sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR);
+
+ if (sdesc->cyclic) {
+ writel((1 << cid) | 1 << (cid + 16) |
+ readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
+ schan->happened_cyclic = schan->completed_cyclic = 0;
+ }
+}
+
+/* Interrupt handler */
+static irqreturn_t sirfsoc_dma_irq(int irq, void *data)
+{
+ struct sirfsoc_dma *sdma = data;
+ struct sirfsoc_dma_chan *schan;
+ struct sirfsoc_dma_desc *sdesc = NULL;
+ u32 is;
+ int ch;
+
+ is = readl(sdma->base + SIRFSOC_DMA_CH_INT);
+ while ((ch = fls(is) - 1) >= 0) {
+ is &= ~(1 << ch);
+ writel_relaxed(1 << ch, sdma->base + SIRFSOC_DMA_CH_INT);
+ schan = &sdma->channels[ch];
+
+ spin_lock(&schan->lock);
+
+ sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
+ node);
+ if (!sdesc->cyclic) {
+ /* Execute queued descriptors */
+ list_splice_tail_init(&schan->active, &schan->completed);
+ if (!list_empty(&schan->queued))
+ sirfsoc_dma_execute(schan);
+ } else
+ schan->happened_cyclic++;
+
+ spin_unlock(&schan->lock);
+ }
+
+ /* Schedule tasklet */
+ tasklet_schedule(&sdma->tasklet);
+
+ return IRQ_HANDLED;
+}
+
+/* process completed descriptors */
+static void sirfsoc_dma_process_completed(struct sirfsoc_dma *sdma)
+{
+ dma_cookie_t last_cookie = 0;
+ struct sirfsoc_dma_chan *schan;
+ struct sirfsoc_dma_desc *sdesc;
+ struct dma_async_tx_descriptor *desc;
+ unsigned long flags;
+ unsigned long happened_cyclic;
+ LIST_HEAD(list);
+ int i;
+
+ for (i = 0; i < sdma->dma.chancnt; i++) {
+ schan = &sdma->channels[i];
+
+ /* Get all completed descriptors */
+ spin_lock_irqsave(&schan->lock, flags);
+ if (!list_empty(&schan->completed)) {
+ list_splice_tail_init(&schan->completed, &list);
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ /* Execute callbacks and run dependencies */
+ list_for_each_entry(sdesc, &list, node) {
+ desc = &sdesc->desc;
+
+ if (desc->callback)
+ desc->callback(desc->callback_param);
+
+ last_cookie = desc->cookie;
+ dma_run_dependencies(desc);
+ }
+
+ /* Free descriptors */
+ spin_lock_irqsave(&schan->lock, flags);
+ list_splice_tail_init(&list, &schan->free);
+ schan->chan.completed_cookie = last_cookie;
+ spin_unlock_irqrestore(&schan->lock, flags);
+ } else {
+ /* for cyclic channel, desc is always in active list */
+ sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
+ node);
+
+ if (!sdesc || (sdesc && !sdesc->cyclic)) {
+ /* without active cyclic DMA */
+ spin_unlock_irqrestore(&schan->lock, flags);
+ continue;
+ }
+
+ /* cyclic DMA */
+ happened_cyclic = schan->happened_cyclic;
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ desc = &sdesc->desc;
+ while (happened_cyclic != schan->completed_cyclic) {
+ if (desc->callback)
+ desc->callback(desc->callback_param);
+ schan->completed_cyclic++;
+ }
+ }
+ }
+}
+
+/* DMA Tasklet */
+static void sirfsoc_dma_tasklet(unsigned long data)
+{
+ struct sirfsoc_dma *sdma = (void *)data;
+
+ sirfsoc_dma_process_completed(sdma);
+}
+
+/* Submit descriptor to hardware */
+static dma_cookie_t sirfsoc_dma_tx_submit(struct dma_async_tx_descriptor *txd)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(txd->chan);
+ struct sirfsoc_dma_desc *sdesc;
+ unsigned long flags;
+ dma_cookie_t cookie;
+
+ sdesc = container_of(txd, struct sirfsoc_dma_desc, desc);
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ /* Move descriptor to queue */
+ list_move_tail(&sdesc->node, &schan->queued);
+
+ cookie = dma_cookie_assign(txd);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return cookie;
+}
+
+static int sirfsoc_dma_slave_config(struct dma_chan *chan,
+ struct dma_slave_config *config)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ unsigned long flags;
+
+ if ((config->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) ||
+ (config->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES))
+ return -EINVAL;
+
+ spin_lock_irqsave(&schan->lock, flags);
+ schan->mode = (config->src_maxburst == 4 ? 1 : 0);
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return 0;
+}
+
+static int sirfsoc_dma_terminate_all(struct dma_chan *chan)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
+ int cid = schan->chan.chan_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ if (!sdma->is_marco) {
+ writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) &
+ ~(1 << cid), sdma->base + SIRFSOC_DMA_INT_EN);
+ writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
+ & ~((1 << cid) | 1 << (cid + 16)),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
+ } else {
+ writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_INT_EN_CLR);
+ writel_relaxed((1 << cid) | 1 << (cid + 16),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL_CLR);
+ }
+
+ writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_CH_VALID);
+
+ list_splice_tail_init(&schan->active, &schan->free);
+ list_splice_tail_init(&schan->queued, &schan->free);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return 0;
+}
+
+static int sirfsoc_dma_pause_chan(struct dma_chan *chan)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
+ int cid = schan->chan.chan_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ if (!sdma->is_marco)
+ writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
+ & ~((1 << cid) | 1 << (cid + 16)),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
+ else
+ writel_relaxed((1 << cid) | 1 << (cid + 16),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL_CLR);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return 0;
+}
+
+static int sirfsoc_dma_resume_chan(struct dma_chan *chan)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(&schan->chan);
+ int cid = schan->chan.chan_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ if (!sdma->is_marco)
+ writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL)
+ | ((1 << cid) | 1 << (cid + 16)),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
+ else
+ writel_relaxed((1 << cid) | 1 << (cid + 16),
+ sdma->base + SIRFSOC_DMA_CH_LOOP_CTRL);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return 0;
+}
+
+/* Alloc channel resources */
+static int sirfsoc_dma_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma_desc *sdesc;
+ unsigned long flags;
+ LIST_HEAD(descs);
+ int i;
+
+ pm_runtime_get_sync(sdma->dma.dev);
+
+ /* Alloc descriptors for this channel */
+ for (i = 0; i < SIRFSOC_DMA_DESCRIPTORS; i++) {
+ sdesc = kzalloc(sizeof(*sdesc), GFP_KERNEL);
+ if (!sdesc) {
+ dev_notice(sdma->dma.dev, "Memory allocation error. "
+ "Allocated only %u descriptors\n", i);
+ break;
+ }
+
+ dma_async_tx_descriptor_init(&sdesc->desc, chan);
+ sdesc->desc.flags = DMA_CTRL_ACK;
+ sdesc->desc.tx_submit = sirfsoc_dma_tx_submit;
+
+ list_add_tail(&sdesc->node, &descs);
+ }
+
+ /* Return error only if no descriptors were allocated */
+ if (i == 0)
+ return -ENOMEM;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ list_splice_tail_init(&descs, &schan->free);
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return i;
+}
+
+/* Free channel resources */
+static void sirfsoc_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
+ struct sirfsoc_dma_desc *sdesc, *tmp;
+ unsigned long flags;
+ LIST_HEAD(descs);
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ /* Channel must be idle */
+ BUG_ON(!list_empty(&schan->prepared));
+ BUG_ON(!list_empty(&schan->queued));
+ BUG_ON(!list_empty(&schan->active));
+ BUG_ON(!list_empty(&schan->completed));
+
+ /* Move data */
+ list_splice_tail_init(&schan->free, &descs);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ /* Free descriptors */
+ list_for_each_entry_safe(sdesc, tmp, &descs, node)
+ kfree(sdesc);
+
+ pm_runtime_put(sdma->dma.dev);
+}
+
+/* Send pending descriptor to hardware */
+static void sirfsoc_dma_issue_pending(struct dma_chan *chan)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ if (list_empty(&schan->active) && !list_empty(&schan->queued))
+ sirfsoc_dma_execute(schan);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+}
+
+/* Check request completion status */
+static enum dma_status
+sirfsoc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ unsigned long flags;
+ enum dma_status ret;
+ struct sirfsoc_dma_desc *sdesc;
+ int cid = schan->chan.chan_id;
+ unsigned long dma_pos;
+ unsigned long dma_request_bytes;
+ unsigned long residue;
+
+ spin_lock_irqsave(&schan->lock, flags);
+
+ sdesc = list_first_entry(&schan->active, struct sirfsoc_dma_desc,
+ node);
+ dma_request_bytes = (sdesc->xlen + 1) * (sdesc->ylen + 1) *
+ (sdesc->width * SIRFSOC_DMA_WORD_LEN);
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ dma_pos = readl_relaxed(sdma->base + cid * 0x10 + SIRFSOC_DMA_CH_ADDR)
+ << 2;
+ residue = dma_request_bytes - (dma_pos - sdesc->addr);
+ dma_set_residue(txstate, residue);
+
+ spin_unlock_irqrestore(&schan->lock, flags);
+
+ return ret;
+}
+
+static struct dma_async_tx_descriptor *sirfsoc_dma_prep_interleaved(
+ struct dma_chan *chan, struct dma_interleaved_template *xt,
+ unsigned long flags)
+{
+ struct sirfsoc_dma *sdma = dma_chan_to_sirfsoc_dma(chan);
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma_desc *sdesc = NULL;
+ unsigned long iflags;
+ int ret;
+
+ if ((xt->dir != DMA_MEM_TO_DEV) && (xt->dir != DMA_DEV_TO_MEM)) {
+ ret = -EINVAL;
+ goto err_dir;
+ }
+
+ /* Get free descriptor */
+ spin_lock_irqsave(&schan->lock, iflags);
+ if (!list_empty(&schan->free)) {
+ sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc,
+ node);
+ list_del(&sdesc->node);
+ }
+ spin_unlock_irqrestore(&schan->lock, iflags);
+
+ if (!sdesc) {
+ /* try to free completed descriptors */
+ sirfsoc_dma_process_completed(sdma);
+ ret = 0;
+ goto no_desc;
+ }
+
+ /* Place descriptor in prepared list */
+ spin_lock_irqsave(&schan->lock, iflags);
+
+ /*
+ * Number of chunks in a frame can only be 1 for prima2
+ * and ylen (number of frame - 1) must be at least 0
+ */
+ if ((xt->frame_size == 1) && (xt->numf > 0)) {
+ sdesc->cyclic = 0;
+ sdesc->xlen = xt->sgl[0].size / SIRFSOC_DMA_WORD_LEN;
+ sdesc->width = (xt->sgl[0].size + xt->sgl[0].icg) /
+ SIRFSOC_DMA_WORD_LEN;
+ sdesc->ylen = xt->numf - 1;
+ if (xt->dir == DMA_MEM_TO_DEV) {
+ sdesc->addr = xt->src_start;
+ sdesc->dir = 1;
+ } else {
+ sdesc->addr = xt->dst_start;
+ sdesc->dir = 0;
+ }
+
+ list_add_tail(&sdesc->node, &schan->prepared);
+ } else {
+ pr_err("sirfsoc DMA Invalid xfer\n");
+ ret = -EINVAL;
+ goto err_xfer;
+ }
+ spin_unlock_irqrestore(&schan->lock, iflags);
+
+ return &sdesc->desc;
+err_xfer:
+ spin_unlock_irqrestore(&schan->lock, iflags);
+no_desc:
+err_dir:
+ return ERR_PTR(ret);
+}
+
+static struct dma_async_tx_descriptor *
+sirfsoc_dma_prep_cyclic(struct dma_chan *chan, dma_addr_t addr,
+ size_t buf_len, size_t period_len,
+ enum dma_transfer_direction direction, unsigned long flags)
+{
+ struct sirfsoc_dma_chan *schan = dma_chan_to_sirfsoc_dma_chan(chan);
+ struct sirfsoc_dma_desc *sdesc = NULL;
+ unsigned long iflags;
+
+ /*
+ * we only support cycle transfer with 2 period
+ * If the X-length is set to 0, it would be the loop mode.
+ * The DMA address keeps increasing until reaching the end of a loop
+ * area whose size is defined by (DMA_WIDTH x (Y_LENGTH + 1)). Then
+ * the DMA address goes back to the beginning of this area.
+ * In loop mode, the DMA data region is divided into two parts, BUFA
+ * and BUFB. DMA controller generates interrupts twice in each loop:
+ * when the DMA address reaches the end of BUFA or the end of the
+ * BUFB
+ */
+ if (buf_len != 2 * period_len)
+ return ERR_PTR(-EINVAL);
+
+ /* Get free descriptor */
+ spin_lock_irqsave(&schan->lock, iflags);
+ if (!list_empty(&schan->free)) {
+ sdesc = list_first_entry(&schan->free, struct sirfsoc_dma_desc,
+ node);
+ list_del(&sdesc->node);
+ }
+ spin_unlock_irqrestore(&schan->lock, iflags);
+
+ if (!sdesc)
+ return NULL;
+
+ /* Place descriptor in prepared list */
+ spin_lock_irqsave(&schan->lock, iflags);
+ sdesc->addr = addr;
+ sdesc->cyclic = 1;
+ sdesc->xlen = 0;
+ sdesc->ylen = buf_len / SIRFSOC_DMA_WORD_LEN - 1;
+ sdesc->width = 1;
+ list_add_tail(&sdesc->node, &schan->prepared);
+ spin_unlock_irqrestore(&schan->lock, iflags);
+
+ return &sdesc->desc;
+}
+
+/*
+ * The DMA controller consists of 16 independent DMA channels.
+ * Each channel is allocated to a different function
+ */
+bool sirfsoc_dma_filter_id(struct dma_chan *chan, void *chan_id)
+{
+ unsigned int ch_nr = (unsigned int) chan_id;
+
+ if (ch_nr == chan->chan_id +
+ chan->device->dev_id * SIRFSOC_DMA_CHANNELS)
+ return true;
+
+ return false;
+}
+EXPORT_SYMBOL(sirfsoc_dma_filter_id);
+
+#define SIRFSOC_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))
+
+static struct dma_chan *of_dma_sirfsoc_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct sirfsoc_dma *sdma = ofdma->of_dma_data;
+ unsigned int request = dma_spec->args[0];
+
+ if (request >= SIRFSOC_DMA_CHANNELS)
+ return NULL;
+
+ return dma_get_slave_channel(&sdma->channels[request].chan);
+}
+
+static int sirfsoc_dma_probe(struct platform_device *op)
+{
+ struct device_node *dn = op->dev.of_node;
+ struct device *dev = &op->dev;
+ struct dma_device *dma;
+ struct sirfsoc_dma *sdma;
+ struct sirfsoc_dma_chan *schan;
+ struct resource res;
+ ulong regs_start, regs_size;
+ u32 id;
+ int ret, i;
+
+ sdma = devm_kzalloc(dev, sizeof(*sdma), GFP_KERNEL);
+ if (!sdma) {
+ dev_err(dev, "Memory exhausted!\n");
+ return -ENOMEM;
+ }
+
+ if (of_device_is_compatible(dn, "sirf,marco-dmac"))
+ sdma->is_marco = true;
+
+ if (of_property_read_u32(dn, "cell-index", &id)) {
+ dev_err(dev, "Fail to get DMAC index\n");
+ return -ENODEV;
+ }
+
+ sdma->irq = irq_of_parse_and_map(dn, 0);
+ if (sdma->irq == NO_IRQ) {
+ dev_err(dev, "Error mapping IRQ!\n");
+ return -EINVAL;
+ }
+
+ sdma->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(sdma->clk)) {
+ dev_err(dev, "failed to get a clock.\n");
+ return PTR_ERR(sdma->clk);
+ }
+
+ ret = of_address_to_resource(dn, 0, &res);
+ if (ret) {
+ dev_err(dev, "Error parsing memory region!\n");
+ goto irq_dispose;
+ }
+
+ regs_start = res.start;
+ regs_size = resource_size(&res);
+
+ sdma->base = devm_ioremap(dev, regs_start, regs_size);
+ if (!sdma->base) {
+ dev_err(dev, "Error mapping memory region!\n");
+ ret = -ENOMEM;
+ goto irq_dispose;
+ }
+
+ ret = request_irq(sdma->irq, &sirfsoc_dma_irq, 0, DRV_NAME, sdma);
+ if (ret) {
+ dev_err(dev, "Error requesting IRQ!\n");
+ ret = -EINVAL;
+ goto irq_dispose;
+ }
+
+ dma = &sdma->dma;
+ dma->dev = dev;
+
+ dma->device_alloc_chan_resources = sirfsoc_dma_alloc_chan_resources;
+ dma->device_free_chan_resources = sirfsoc_dma_free_chan_resources;
+ dma->device_issue_pending = sirfsoc_dma_issue_pending;
+ dma->device_config = sirfsoc_dma_slave_config;
+ dma->device_pause = sirfsoc_dma_pause_chan;
+ dma->device_resume = sirfsoc_dma_resume_chan;
+ dma->device_terminate_all = sirfsoc_dma_terminate_all;
+ dma->device_tx_status = sirfsoc_dma_tx_status;
+ dma->device_prep_interleaved_dma = sirfsoc_dma_prep_interleaved;
+ dma->device_prep_dma_cyclic = sirfsoc_dma_prep_cyclic;
+ dma->src_addr_widths = SIRFSOC_DMA_BUSWIDTHS;
+ dma->dst_addr_widths = SIRFSOC_DMA_BUSWIDTHS;
+ dma->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+
+ INIT_LIST_HEAD(&dma->channels);
+ dma_cap_set(DMA_SLAVE, dma->cap_mask);
+ dma_cap_set(DMA_CYCLIC, dma->cap_mask);
+ dma_cap_set(DMA_INTERLEAVE, dma->cap_mask);
+ dma_cap_set(DMA_PRIVATE, dma->cap_mask);
+
+ for (i = 0; i < SIRFSOC_DMA_CHANNELS; i++) {
+ schan = &sdma->channels[i];
+
+ schan->chan.device = dma;
+ dma_cookie_init(&schan->chan);
+
+ INIT_LIST_HEAD(&schan->free);
+ INIT_LIST_HEAD(&schan->prepared);
+ INIT_LIST_HEAD(&schan->queued);
+ INIT_LIST_HEAD(&schan->active);
+ INIT_LIST_HEAD(&schan->completed);
+
+ spin_lock_init(&schan->lock);
+ list_add_tail(&schan->chan.device_node, &dma->channels);
+ }
+
+ tasklet_init(&sdma->tasklet, sirfsoc_dma_tasklet, (unsigned long)sdma);
+
+ /* Register DMA engine */
+ dev_set_drvdata(dev, sdma);
+
+ ret = dma_async_device_register(dma);
+ if (ret)
+ goto free_irq;
+
+ /* Device-tree DMA controller registration */
+ ret = of_dma_controller_register(dn, of_dma_sirfsoc_xlate, sdma);
+ if (ret) {
+ dev_err(dev, "failed to register DMA controller\n");
+ goto unreg_dma_dev;
+ }
+
+ pm_runtime_enable(&op->dev);
+ dev_info(dev, "initialized SIRFSOC DMAC driver\n");
+
+ return 0;
+
+unreg_dma_dev:
+ dma_async_device_unregister(dma);
+free_irq:
+ free_irq(sdma->irq, sdma);
+irq_dispose:
+ irq_dispose_mapping(sdma->irq);
+ return ret;
+}
+
+static int sirfsoc_dma_remove(struct platform_device *op)
+{
+ struct device *dev = &op->dev;
+ struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
+
+ of_dma_controller_free(op->dev.of_node);
+ dma_async_device_unregister(&sdma->dma);
+ free_irq(sdma->irq, sdma);
+ irq_dispose_mapping(sdma->irq);
+ pm_runtime_disable(&op->dev);
+ if (!pm_runtime_status_suspended(&op->dev))
+ sirfsoc_dma_runtime_suspend(&op->dev);
+
+ return 0;
+}
+
+static int sirfsoc_dma_runtime_suspend(struct device *dev)
+{
+ struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(sdma->clk);
+ return 0;
+}
+
+static int sirfsoc_dma_runtime_resume(struct device *dev)
+{
+ struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(sdma->clk);
+ if (ret < 0) {
+ dev_err(dev, "clk_enable failed: %d\n", ret);
+ return ret;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int sirfsoc_dma_pm_suspend(struct device *dev)
+{
+ struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
+ struct sirfsoc_dma_regs *save = &sdma->regs_save;
+ struct sirfsoc_dma_desc *sdesc;
+ struct sirfsoc_dma_chan *schan;
+ int ch;
+ int ret;
+
+ /*
+ * if we were runtime-suspended before, resume to enable clock
+ * before accessing register
+ */
+ if (pm_runtime_status_suspended(dev)) {
+ ret = sirfsoc_dma_runtime_resume(dev);
+ if (ret < 0)
+ return ret;
+ }
+
+ /*
+ * DMA controller will lose all registers while suspending
+ * so we need to save registers for active channels
+ */
+ for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
+ schan = &sdma->channels[ch];
+ if (list_empty(&schan->active))
+ continue;
+ sdesc = list_first_entry(&schan->active,
+ struct sirfsoc_dma_desc,
+ node);
+ save->ctrl[ch] = readl_relaxed(sdma->base +
+ ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
+ }
+ save->interrupt_en = readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN);
+
+ /* Disable clock */
+ sirfsoc_dma_runtime_suspend(dev);
+
+ return 0;
+}
+
+static int sirfsoc_dma_pm_resume(struct device *dev)
+{
+ struct sirfsoc_dma *sdma = dev_get_drvdata(dev);
+ struct sirfsoc_dma_regs *save = &sdma->regs_save;
+ struct sirfsoc_dma_desc *sdesc;
+ struct sirfsoc_dma_chan *schan;
+ int ch;
+ int ret;
+
+ /* Enable clock before accessing register */
+ ret = sirfsoc_dma_runtime_resume(dev);
+ if (ret < 0)
+ return ret;
+
+ writel_relaxed(save->interrupt_en, sdma->base + SIRFSOC_DMA_INT_EN);
+ for (ch = 0; ch < SIRFSOC_DMA_CHANNELS; ch++) {
+ schan = &sdma->channels[ch];
+ if (list_empty(&schan->active))
+ continue;
+ sdesc = list_first_entry(&schan->active,
+ struct sirfsoc_dma_desc,
+ node);
+ writel_relaxed(sdesc->width,
+ sdma->base + SIRFSOC_DMA_WIDTH_0 + ch * 4);
+ writel_relaxed(sdesc->xlen,
+ sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_XLEN);
+ writel_relaxed(sdesc->ylen,
+ sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_YLEN);
+ writel_relaxed(save->ctrl[ch],
+ sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_CTRL);
+ writel_relaxed(sdesc->addr >> 2,
+ sdma->base + ch * 0x10 + SIRFSOC_DMA_CH_ADDR);
+ }
+
+ /* if we were runtime-suspended before, suspend again */
+ if (pm_runtime_status_suspended(dev))
+ sirfsoc_dma_runtime_suspend(dev);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops sirfsoc_dma_pm_ops = {
+ SET_RUNTIME_PM_OPS(sirfsoc_dma_runtime_suspend, sirfsoc_dma_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_dma_pm_suspend, sirfsoc_dma_pm_resume)
+};
+
+static const struct of_device_id sirfsoc_dma_match[] = {
+ { .compatible = "sirf,prima2-dmac", },
+ { .compatible = "sirf,marco-dmac", },
+ {},
+};
+
+static struct platform_driver sirfsoc_dma_driver = {
+ .probe = sirfsoc_dma_probe,
+ .remove = sirfsoc_dma_remove,
+ .driver = {
+ .name = DRV_NAME,
+ .pm = &sirfsoc_dma_pm_ops,
+ .of_match_table = sirfsoc_dma_match,
+ },
+};
+
+static __init int sirfsoc_dma_init(void)
+{
+ return platform_driver_register(&sirfsoc_dma_driver);
+}
+
+static void __exit sirfsoc_dma_exit(void)
+{
+ platform_driver_unregister(&sirfsoc_dma_driver);
+}
+
+subsys_initcall(sirfsoc_dma_init);
+module_exit(sirfsoc_dma_exit);
+
+MODULE_AUTHOR("Rongjun Ying <rongjun.ying@csr.com>, "
+ "Barry Song <baohua.song@csr.com>");
+MODULE_DESCRIPTION("SIRFSOC DMA control driver");
+MODULE_LICENSE("GPL v2");