[RFC PATCH 03/11] dma: amba-pl08x: Add support for different offset of CONFIG register

From: Tomasz Figa
Date: Sun Jun 16 2013 - 16:56:57 EST


Some variants of PL08x (namely PL080S, found in Samsung S3C64xx SoCs)
have CONFIG register at different offset. This patch makes the driver
use offset from vendor data struct.

Signed-off-by: Tomasz Figa <tomasz.figa@xxxxxxxxx>
---
drivers/dma/amba-pl08x.c | 51 ++++++++++++++++++++++++++++--------------------
1 file changed, 30 insertions(+), 21 deletions(-)

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 1e57ded..93913b4 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -107,6 +107,7 @@ struct pl08x_driver_data;
* @flags: Vendor-specific flags, see PL08X_IS_*
*/
struct vendor_data {
+ u8 config_offset;
u8 channels;
u32 flags;
};
@@ -334,11 +335,12 @@ static void pl08x_release_mux(struct pl08x_dma_chan *plchan)
*/

/* Whether a certain channel is busy or not */
-static int pl08x_phy_channel_busy(struct pl08x_phy_chan *ch)
+static int pl08x_phy_channel_busy(struct pl08x_driver_data *pl08x,
+ struct pl08x_phy_chan *ch)
{
unsigned int val;

- val = readl(ch->base + PL080_CH_CONFIG);
+ val = readl(ch->base + pl08x->vd->config_offset);
return val & PL080_CONFIG_ACTIVE;
}

@@ -362,7 +364,7 @@ static void pl08x_start_next_txd(struct pl08x_dma_chan *plchan)
plchan->at = txd;

/* Wait for channel inactive */
- while (pl08x_phy_channel_busy(phychan))
+ while (pl08x_phy_channel_busy(pl08x, phychan))
cpu_relax();

lli = &txd->llis_va[0];
@@ -377,7 +379,7 @@ static void pl08x_start_next_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);
+ writel(txd->ccfg, phychan->base + pl08x->vd->config_offset);

/* Enable the DMA channel */
/* Do not access config register until channel shows as disabled */
@@ -385,11 +387,13 @@ static void pl08x_start_next_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);
+
+ val = readl(phychan->base + pl08x->vd->config_offset);
while ((val & PL080_CONFIG_ACTIVE) || (val & PL080_CONFIG_ENABLE))
- val = readl(phychan->base + PL080_CH_CONFIG);
+ val = readl(phychan->base + pl08x->vd->config_offset);

- writel(val | PL080_CONFIG_ENABLE, phychan->base + PL080_CH_CONFIG);
+ writel(val | PL080_CONFIG_ENABLE,
+ phychan->base + pl08x->vd->config_offset);
}

/*
@@ -402,34 +406,36 @@ static void pl08x_start_next_txd(struct pl08x_dma_chan *plchan)
* For P->M transfers, disable the peripheral first to stop it filling
* the DMAC FIFO, and then pause the DMAC.
*/
-static void pl08x_pause_phy_chan(struct pl08x_phy_chan *ch)
+static void pl08x_pause_phy_chan(struct pl08x_driver_data *pl08x,
+ struct pl08x_phy_chan *ch)
{
u32 val;
int timeout;

/* Set the HALT bit and wait for the FIFO to drain */
- val = readl(ch->base + PL080_CH_CONFIG);
+ val = readl(ch->base + pl08x->vd->config_offset);
val |= PL080_CONFIG_HALT;
- writel(val, ch->base + PL080_CH_CONFIG);
+ writel(val, ch->base + pl08x->vd->config_offset);

/* Wait for channel inactive */
for (timeout = 1000; timeout; timeout--) {
- if (!pl08x_phy_channel_busy(ch))
+ if (!pl08x_phy_channel_busy(pl08x, ch))
break;
udelay(1);
}
- if (pl08x_phy_channel_busy(ch))
+ if (pl08x_phy_channel_busy(pl08x, ch))
pr_err("pl08x: channel%u timeout waiting for pause\n", ch->id);
}

-static void pl08x_resume_phy_chan(struct pl08x_phy_chan *ch)
+static void pl08x_resume_phy_chan(struct pl08x_driver_data *pl08x,
+ struct pl08x_phy_chan *ch)
{
u32 val;

/* Clear the HALT bit */
- val = readl(ch->base + PL080_CH_CONFIG);
+ val = readl(ch->base + pl08x->vd->config_offset);
val &= ~PL080_CONFIG_HALT;
- writel(val, ch->base + PL080_CH_CONFIG);
+ writel(val, ch->base + pl08x->vd->config_offset);
}

/*
@@ -441,12 +447,12 @@ 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);
+ u32 val = readl(ch->base + pl08x->vd->config_offset);

val &= ~(PL080_CONFIG_ENABLE | PL080_CONFIG_ERR_IRQ_MASK |
PL080_CONFIG_TC_IRQ_MASK);

- writel(val, ch->base + PL080_CH_CONFIG);
+ writel(val, ch->base + pl08x->vd->config_offset);

writel(1 << ch->id, pl08x->base + PL080_ERR_CLEAR);
writel(1 << ch->id, pl08x->base + PL080_TC_CLEAR);
@@ -1576,11 +1582,11 @@ static int pl08x_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
pl08x_free_txd_list(pl08x, plchan);
break;
case DMA_PAUSE:
- pl08x_pause_phy_chan(plchan->phychan);
+ pl08x_pause_phy_chan(pl08x, plchan->phychan);
plchan->state = PL08X_CHAN_PAUSED;
break;
case DMA_RESUME:
- pl08x_resume_phy_chan(plchan->phychan);
+ pl08x_resume_phy_chan(pl08x, plchan->phychan);
plchan->state = PL08X_CHAN_RUNNING;
break;
default:
@@ -1966,7 +1972,7 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
if (vd->flags & PL08X_IS_NOMADIK) {
u32 val;

- val = readl(ch->base + PL080_CH_CONFIG);
+ val = readl(ch->base + vd->config_offset);
if (val & (PL080N_CONFIG_ITPROT | PL080N_CONFIG_SECPROT)) {
dev_info(&adev->dev, "physical channel %d reserved for secure access only\n", i);
ch->locked = true;
@@ -1974,7 +1980,7 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id)
}

dev_dbg(&adev->dev, "physical channel %d is %s\n",
- i, pl08x_phy_channel_busy(ch) ? "BUSY" : "FREE");
+ i, pl08x_phy_channel_busy(pl08x, ch) ? "BUSY" : "FREE");
}

/* Register as many memcpy channels as there are physical channels */
@@ -2049,16 +2055,19 @@ out_no_pl08x:
static struct vendor_data vendor_pl080 = {
.channels = 8,
.flags = PL08X_IS_DUALMASTER,
+ .config_offset = PL080_CH_CONFIG,
};

static struct vendor_data vendor_nomadik = {
.channels = 8,
.flags = PL08X_IS_DUALMASTER | PL08X_IS_NOMADIK,
+ .config_offset = PL080_CH_CONFIG,
};

static struct vendor_data vendor_pl081 = {
.channels = 2,
.flags = 0,
+ .config_offset = PL080_CH_CONFIG,
};

static struct amba_id pl08x_ids[] = {
--
1.8.2.1

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