[PATCH] DMAENGINE: ste_dma40: support older silicon

From: Linus Walleij
Date: Mon Jun 07 2010 - 05:41:08 EST


This makes sure the DMA40 driver will also work on the oldest
silicon revisions that have the on-chip memory on another location
in the DB8500 and also requires explicit suspend before starting
or resuming a logical channel.

Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxxxxxx>
---
Dan: this patch applies on top of the previous 18 patches, sorry
for the spamming but they are atleaset quite clearly cut and broken
down.
---
arch/arm/mach-ux500/devices-db8500.c | 2 +
arch/arm/mach-ux500/include/mach/db8500-regs.h | 1 +
drivers/dma/ste_dma40.c | 32 +++++++++++++++++++++---
3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-ux500/devices-db8500.c b/arch/arm/mach-ux500/devices-db8500.c
index e2b7c31..c62cdbe 100644
--- a/arch/arm/mach-ux500/devices-db8500.c
+++ b/arch/arm/mach-ux500/devices-db8500.c
@@ -213,4 +213,6 @@ void dma40_u8500ed_fixup(void)
dma40_plat_data.memcpy_len = 0;
dma40_resources[0].start = U8500_DMA_BASE_ED;
dma40_resources[0].end = U8500_DMA_BASE_ED + SZ_4K - 1;
+ dma40_resources[1].start = U8500_DMA_LCPA_BASE_ED;
+ dma40_resources[1].end = U8500_DMA_LCPA_BASE_ED + 2 * SZ_1K - 1;
}
diff --git a/arch/arm/mach-ux500/include/mach/db8500-regs.h b/arch/arm/mach-ux500/include/mach/db8500-regs.h
index 897fa35..8a8646b 100644
--- a/arch/arm/mach-ux500/include/mach/db8500-regs.h
+++ b/arch/arm/mach-ux500/include/mach/db8500-regs.h
@@ -17,6 +17,7 @@
#define U8500_ESRAM_BANK4 (U8500_ESRAM_BANK3 + U8500_ESRAM_BANK_SIZE)
/* Use bank 4 for DMA LCPA */
#define U8500_DMA_LCPA_BASE U8500_ESRAM_BANK4
+#define U8500_DMA_LCPA_BASE_ED U8500_ESRAM_BANK4 + 0x4000

#define U8500_PER3_BASE 0x80000000
#define U8500_STM_BASE 0x80100000
diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 0829ddb..4ab86b0 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -218,6 +218,7 @@ struct d40_chan {
* the same physical register.
* @dev: The device structure.
* @virtbase: The virtual base address of the DMA's register.
+ * @rev: silicon revision detected.
* @clk: Pointer to the DMA clock structure.
* @phy_start: Physical memory start of the DMA registers.
* @phy_size: Size of the DMA register map.
@@ -250,6 +251,7 @@ struct d40_base {
spinlock_t execmd_lock;
struct device *dev;
void __iomem *virtbase;
+ u8 rev:4;
struct clk *clk;
phys_addr_t phy_start;
resource_size_t phy_size;
@@ -757,6 +759,17 @@ static dma_cookie_t d40_tx_submit(struct dma_async_tx_descriptor *tx)

static int d40_start(struct d40_chan *d40c)
{
+ if (d40c->base->rev == 0) {
+ int err;
+
+ if (d40c->log_num != D40_PHY_CHAN) {
+ err = d40_channel_execute_command(d40c,
+ D40_DMA_SUSPEND_REQ);
+ if (err)
+ return err;
+ }
+ }
+
if (d40c->log_num != D40_PHY_CHAN)
d40_config_set_event(d40c, true);

@@ -1456,6 +1469,13 @@ static int d40_resume(struct dma_chan *chan)

spin_lock_irqsave(&d40c->lock, flags);

+ if (d40c->base->rev == 0)
+ if (d40c->log_num != D40_PHY_CHAN) {
+ res = d40_channel_execute_command(d40c,
+ D40_DMA_SUSPEND_REQ);
+ goto no_suspend;
+ }
+
/* If bytes left to transfer or linked tx resume job */
if (d40_residue(d40c) || d40_tx_is_linked(d40c)) {
if (d40c->log_num != D40_PHY_CHAN)
@@ -1463,6 +1483,7 @@ static int d40_resume(struct dma_chan *chan)
res = d40_channel_execute_command(d40c, D40_DMA_RUN);
}

+no_suspend:
spin_unlock_irqrestore(&d40c->lock, flags);
return res;
}
@@ -2292,6 +2313,7 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
int num_log_chans = 0;
int num_phy_chans;
int i;
+ u32 val;

clk = clk_get(&pdev->dev, NULL);

@@ -2330,12 +2352,13 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
}
}

- i = readl(virtbase + D40_DREG_PERIPHID2);
+ /* Get silicon revision */
+ val = readl(virtbase + D40_DREG_PERIPHID2);

- if ((i & 0xf) != D40_PERIPHID2_DESIGNER) {
+ if ((val & 0xf) != D40_PERIPHID2_DESIGNER) {
dev_err(&pdev->dev,
"[%s] Unknown designer! Got %x wanted %x\n",
- __func__, i & 0xf, D40_PERIPHID2_DESIGNER);
+ __func__, val & 0xf, D40_PERIPHID2_DESIGNER);
goto failure;
}

@@ -2343,7 +2366,7 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
num_phy_chans = 4 * (readl(virtbase + D40_DREG_ICFG) & 0x7) + 4;

dev_info(&pdev->dev, "hardware revision: %d @ 0x%x\n",
- (i >> 4) & 0xf, res->start);
+ (val >> 4) & 0xf, res->start);

plat_data = pdev->dev.platform_data;

@@ -2365,6 +2388,7 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
goto failure;
}

+ base->rev = (val >> 4) & 0xf;
base->clk = clk;
base->num_phy_chans = num_phy_chans;
base->num_log_chans = num_log_chans;
--
1.6.3.3

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