[PATCH V2 1/1] dmaengine/amba-pl08x: Add support for s3c64xx DMAC
Alim Akhtar
alim.akhtar at samsung.com
Wed Sep 28 01:50:07 EDT 2011
Signed-off-by: Alim Akhtar <alim.akhtar at samsung.com>
---
drivers/dma/amba-pl08x.c | 135 ++++++++++++++++++++++++++++++++++++++--------
1 files changed, 112 insertions(+), 23 deletions(-)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index cd8df7f..501540f 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -66,8 +66,25 @@
* after the final transfer signalled by LBREQ or LSREQ. The DMAC
* will then move to the next LLI entry.
*
- * Global TODO:
- * - Break out common code from arch/arm/mach-s3c64xx and share
+ * Samsung S3C64xx SoCs uses a variant of PL080 DMAC. It contains an extra
+ * control register to hold the TransferSize. Below is the LLI structure
+ * and offsets of S3C64xx DMAC.
+ * -----------------------------------------------------------------
+ * | Offset | Contents |
+ * -----------------------------------------------------------------
+ * | Next LLI Address | Source Address for Next xfer |
+ * -----------------------------------------------------------------
+ * | Next LLI Address+0x04 | Destination Address for Next xfer |
+ * -----------------------------------------------------------------
+ * | Next LLI Address+0x08 | Next LLI address for next xfer |
+ * -----------------------------------------------------------------
+ * | Next LLI Address+0x0c | DMACCxControl0 data for next xfer |
+ * -----------------------------------------------------------------
+ * | Next LLI Address+0x10 | DMACCxControl1 xfer size for next xfer|
+ * -----------------------------------------------------------------
+ * Also S3C64XX has a config register at offset 0x14
+ * Have a look at arch/arm/include/asm/hardware/pl080.h for complete register
+ * details.
*/
#include <linux/amba/bus.h>
#include <linux/amba/pl08x.h>
@@ -97,6 +114,8 @@ static struct amba_driver pl08x_amba_driver;
struct vendor_data {
u8 channels;
bool dualmaster;
+ /* To identify samsung DMAC */
+ bool is_pl080_s3c;
};
/*
@@ -110,6 +129,11 @@ struct pl08x_lli {
u32 dst;
u32 lli;
u32 cctl;
+ /*
+ * Samsung pl080 DMAC has one exrta control register
+ * which is used to hold the transfer_size
+ */
+ u32 cctl1;
};
/**
@@ -171,9 +195,20 @@ static inline struct pl08x_txd *to_pl08x_txd(struct dma_async_tx_descriptor *tx)
/* Whether a certain channel is busy or not */
static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch)
{
+ struct pl08x_dma_chan *plchan = ch->serving;
+ struct pl08x_driver_data *pl08x;
unsigned int val;
- val = readl(ch->base + PL080_CH_CONFIG);
+ if (plchan == NULL)
+ return false;
+
+ pl08x = plchan->host;
+
+ if (pl08x->vd->is_pl080_s3c)
+ val = readl(ch->base + PL080S_CH_CONFIG);
+ else
+ val = readl(ch->base + PL080_CH_CONFIG);
+
return val & PL080_CONFIG_ACTIVE;
}
@@ -207,7 +242,12 @@ static void pl08x_start_txd(struct pl08x_dma_chan *plchan,
writel(lli->dst, phychan->base + PL080_CH_DST_ADDR);
writel(lli->lli, phychan->base + PL080_CH_LLI);
writel(lli->cctl, phychan->base + PL080_CH_CONTROL);
- writel(txd->ccfg, phychan->base + PL080_CH_CONFIG);
+
+ if (pl08x->vd->is_pl080_s3c) {
+ writel(txd->ccfg, phychan->base + PL080S_CH_CONFIG);
+ writel(lli->cctl1, phychan->base + PL080S_CH_CONTROL2);
+ } else
+ writel(txd->ccfg, phychan->base + PL080_CH_CONFIG);
/* Enable the DMA channel */
/* Do not access config register until channel shows as disabled */
@@ -215,11 +255,23 @@ static void pl08x_start_txd(struct pl08x_dma_chan *plchan,
cpu_relax();
/* Do not access config register until channel shows as inactive */
- val = readl(phychan->base + PL080_CH_CONFIG);
- while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE))
+ if (pl08x->vd->is_pl080_s3c) {
+ val = readl(phychan->base + PL080S_CH_CONFIG);
+ while ((val & PL080_CONFIG_ACTIVE) ||
+ (val & PL080_CONFIG_ENABLE))
+ val = readl(phychan->base + PL080S_CH_CONFIG);
+
+ writel(val | PL080_CONFIG_ENABLE,
+ phychan->base + PL080S_CH_CONFIG);
+ } else {
val = readl(phychan->base + PL080_CH_CONFIG);
+ while ((val & PL080_CONFIG_ACTIVE) ||
+ (val & PL080_CONFIG_ENABLE))
+ val = readl(phychan->base + PL080_CH_CONFIG);
- writel(val | PL080_CONFIG_ENABLE, phychan->base + PL080_CH_CONFIG);
+ writel(val | PL080_CONFIG_ENABLE,
+ phychan->base + PL080_CH_CONFIG);
+ }
}
/*
@@ -236,12 +288,19 @@ static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
{
u32 val;
int timeout;
+ struct pl08x_dma_chan *plchan = ch->serving;
+ struct pl08x_driver_data *pl08x = plchan->host;
/* Set the HALT bit and wait for the FIFO to drain */
- val = readl(ch->base + PL080_CH_CONFIG);
- val |= PL080_CONFIG_HALT;
- writel(val, ch->base + PL080_CH_CONFIG);
-
+ if (pl08x->vd->is_pl080_s3c) {
+ val = readl(ch->base + PL080S_CH_CONFIG);
+ val |= PL080_CONFIG_HALT;
+ writel(val, ch->base + PL080S_CH_CONFIG);
+ } else {
+ val = readl(ch->base + PL080_CH_CONFIG);
+ val |= PL080_CONFIG_HALT;
+ writel(val, ch->base + PL080_CH_CONFIG);
+ }
/* Wait for channel inactive */
for (timeout = 1000; timeout; timeout--) {
if (!pl08x_phy_channel_busy(ch))
@@ -255,11 +314,19 @@ static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
{
u32 val;
+ struct pl08x_dma_chan *plchan = ch->serving;
+ struct pl08x_driver_data *pl08x = plchan->host;
/* Clear the HALT bit */
- val = readl(ch->base + PL080_CH_CONFIG);
- val &= ~PL080_CONFIG_HALT;
- writel(val, ch->base + PL080_CH_CONFIG);
+ if (pl08x->vd->is_pl080_s3c) {
+ val = readl(ch->base + PL080S_CH_CONFIG);
+ val &= ~PL080_CONFIG_HALT;
+ writel(val, ch->base + PL080S_CH_CONFIG);
+ } else {
+ val = readl(ch->base + PL080_CH_CONFIG);
+ val &= ~PL080_CONFIG_HALT;
+ writel(val, ch->base + PL080_CH_CONFIG);
+ }
}
/*
@@ -271,12 +338,17 @@ static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
static void pl08x_terminate_phy_chan(struct pl08x_driver_data *pl08x,
struct pl08x_phy_chan *ch)
{
- u32 val = readl(ch->base + PL080_CH_CONFIG);
-
- val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
- PL080_CONFIG_TC_IRQ_MASK);
-
- writel(val, ch->base + PL080_CH_CONFIG);
+ if (pl08x->vd->is_pl080_s3c) {
+ u32 val = readl(ch->base + PL080S_CH_CONFIG);
+ val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
+ PL080_CONFIG_TC_IRQ_MASK);
+ writel(val, ch->base + PL080S_CH_CONFIG);
+ } else {
+ u32 val = readl(ch->base + PL080_CH_CONFIG);
+ val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
+ PL080_CONFIG_TC_IRQ_MASK);
+ writel(val, ch->base + PL080_CH_CONFIG);
+ }
writel(1 << ch->id, pl08x->base + PL080_ERR_CLEAR);
writel(1 << ch->id, pl08x->base + PL080_TC_CLEAR);
@@ -569,6 +641,7 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
u32 cctl, early_bytes = 0;
size_t max_bytes_per_lli, total_bytes = 0;
struct pl08x_lli *llis_va;
+ size_t lli_len = 0, target_len, tsize, odd_bytes;
txd->llis_va = dma_pool_alloc(pl08x->pool, GFP_NOWAIT, &txd->llis_bus);
if (!txd->llis_va) {
@@ -700,7 +773,7 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
* width left
*/
while (bd.remainder > (mbus->buswidth - 1)) {
- size_t lli_len, tsize, width;
+ size_t width;
/*
* If enough left try to send max possible,
@@ -759,6 +832,9 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
llis_va[num_llis - 1].lli = 0;
/* The final LLI element shall also fire an interrupt. */
llis_va[num_llis - 1].cctl |= PL080_CONTROL_TC_IRQ_EN;
+ /* Keep the TransferSize seperate to fill samsung specific register */
+ if (pl08x->vd->is_pl080_s3c)
+ llis_va[num_llis - 1].cctl1 |= lli_len;
#ifdef VERBOSE_DEBUG
{
@@ -771,8 +847,8 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
dev_vdbg(&pl08x->adev->dev,
"%3d @%p: 0x%08x 0x%08x 0x%08x 0x%08x\n",
i, &llis_va[i], llis_va[i].src,
- llis_va[i].dst, llis_va[i].lli, llis_va[i].cctl
- );
+ llis_va[i].dst, llis_va[i].lli,
+ llis_va[i].cctl);
}
}
#endif
@@ -1979,6 +2055,12 @@ static struct vendor_data vendor_pl081 = {
.dualmaster = false,
};
+static struct vendor_data vendor_pl080_s3c = {
+ .channels = 8,
+ .dualmaster = true,
+ .is_pl080_s3c = true,
+};
+
static struct amba_id pl08x_ids[] = {
/* PL080 */
{
@@ -1998,6 +2080,13 @@ static struct amba_id pl08x_ids[] = {
.mask = 0x00ffffff,
.data = &vendor_pl080,
},
+ /* Samsung DMAC is PL080 variant*/
+ {
+ .id = 0x00041082,
+ .mask = 0x000fffff,
+ .data = &vendor_pl080_s3c,
+
+ },
{ 0, 0 },
};
--
1.7.2.3
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