On 8/24/2010 1:04 PM, G, Manjunath Kondaiah wrote:
This patch introduces generic way of handling all OMAP DMA
errata's which are applicable for OMAP1 and OMAP2PLUS processors.
<...>
diff --git a/arch/arm/mach-omap2/dma.c b/arch/arm/mach-omap2/dma.c
index f369bee..8832bd1 100644
--- a/arch/arm/mach-omap2/dma.c
+++ b/arch/arm/mach-omap2/dma.c
@@ -80,6 +80,40 @@ static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *user)
pdata->dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
+ /* Handling Errata's for all OMAP2PLUS processors */
+ pdata->errata = 0;
+
+ if (cpu_is_omap242x() ||
+ (cpu_is_omap243x()&& omap_type()<= OMAP2430_REV_ES1_0))
+ pdata->errata = DMA_CHAINING_ERRATA;
+
+ /*
+ * Errata: On ES2.0 BUFFERING disable must be set.
+ * This will always fail on ES1.0
+ */
+ if (cpu_is_omap24xx())
+ pdata->errata |= DMA_BUFF_DISABLE_ERRATA;
+
+ /*
+ * Errata: OMAP2: sDMA Channel is not disabled
+ * after a transaction error. So we explicitely
+ * disable the channel
+ */
+ if (cpu_class_is_omap2())
+ pdata->errata |= DMA_CH_DISABLE_ERRATA;
+
+ /* Errata: OMAP3 :
+ * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
+ * after secure sram context save and restore. Hence we need to
+ * manually clear those IRQs to avoid spurious interrupts. This
+ * affects only secure devices.
+ */
+ if (cpu_is_omap34xx()&& (omap_type() != OMAP2_DEVICE_TYPE_GP))
+ pdata->errata |= DMA_IRQ_STATUS_ERRATA;
+
+ /* Errata3.3: Applicable for all omap2 plus */
+ pdata->errata |= OMAP3_3_ERRATUM;
+
The DMA_SYSCONFIG_ERRATA does not seems to be initialized there. How are
you enabling that errata?
Benoit
od = omap_device_build(name, 0, oh, pdata, sizeof(*pdata),
omap2_dma_latency, ARRAY_SIZE(omap2_dma_latency), 0);
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 36c3dde..409586a 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -187,6 +187,25 @@ static inline void set_gdma_dev(int req, int dev)
#define set_gdma_dev(req, dev) do {} while (0)
#endif
+static void dma_ocpsysconfig_errata(u32 *sys_cf, bool flag)
+{
+ u32 l;
+
+ /*
+ * DMA Errata:
+ * Special programming model needed to disable DMA before end of block
+ */
+ if (!flag) {
+ *sys_cf = dma_read(OCP_SYSCONFIG);
+ l = *sys_cf;
+ /* Middle mode reg set no Standby */
+ l&= ~((1<< 12)|(1<< 13));
+ dma_write(l, OCP_SYSCONFIG);
+ } else
+ /* put back old value */
+ dma_write(*sys_cf, OCP_SYSCONFIG);
+}
+
/* Omap1 only */
static void clear_lch_regs(int lch)
{
@@ -971,22 +990,16 @@ void omap_start_dma(int lch)
cur_lch = next_lch;
} while (next_lch != -1);
- } else if (cpu_is_omap242x() ||
- (cpu_is_omap243x()&& omap_type()<= OMAP2430_REV_ES1_0)) {
+ }
- /* Errata: Need to write lch even if not using chaining */
+ if (p->errata& DMA_CHAINING_ERRATA)
dma_write(lch, CLNK_CTRL(lch));
- }
omap_enable_channel_irq(lch);
l = dma_read(CCR(lch));
- /*
- * Errata: On ES2.0 BUFFERING disable must be set.
- * This will always fail on ES1.0
- */
- if (cpu_is_omap24xx())
+ if (p->errata& DMA_BUFF_DISABLE_ERRATA)
l |= OMAP_DMA_CCR_EN;
l |= OMAP_DMA_CCR_EN;
@@ -1660,7 +1673,7 @@ int omap_stop_dma_chain_transfers(int chain_id)
{
int *channels;
u32 l, i;
- u32 sys_cf;
+ u32 get_sysconfig;
/* Check for input params */
if (unlikely((chain_id< 0 || chain_id>= dma_lch_count))) {
@@ -1675,15 +1688,8 @@ int omap_stop_dma_chain_transfers(int chain_id)
}
channels = dma_linked_lch[chain_id].linked_dmach_q;
- /*
- * DMA Errata:
- * Special programming model needed to disable DMA before end of block
- */
- sys_cf = dma_read(OCP_SYSCONFIG);
- l = sys_cf;
- /* Middle mode reg set no Standby */
- l&= ~((1<< 12)|(1<< 13));
- dma_write(l, OCP_SYSCONFIG);
+ if (p->errata& DMA_SYSCONFIG_ERRATA)
+ dma_ocpsysconfig_errata(&get_sysconfig, false);
for (i = 0; i< dma_linked_lch[chain_id].no_of_lchs_linked; i++) {
@@ -1702,8 +1708,8 @@ int omap_stop_dma_chain_transfers(int chain_id)
/* Reset the Queue pointers */
OMAP_DMA_CHAIN_QINIT(chain_id);
- /* Errata - put in the old value */
- dma_write(sys_cf, OCP_SYSCONFIG);
+ if (p->errata& DMA_SYSCONFIG_ERRATA)
+ dma_ocpsysconfig_errata(&get_sysconfig, true);
return 0;
}
diff --git a/arch/arm/plat-omap/include/plat/dma.h b/arch/arm/plat-omap/include/plat/dma.h
index a44b11b..ca251ac 100644
--- a/arch/arm/plat-omap/include/plat/dma.h
+++ b/arch/arm/plat-omap/include/plat/dma.h
@@ -269,6 +269,14 @@
#define IS_WORD_16 (1<< 0xC)
#define IS_RW_PRIORIY (1<< 0xD)
+/* Errata Definitions */
+#define DMA_CHAINING_ERRATA (1<< 0)
+#define DMA_BUFF_DISABLE_ERRATA (1<< 1)
+#define OMAP3_3_ERRATUM (1<< 2)
+#define DMA_SYSCONFIG_ERRATA (1<< 3)
+#define DMA_CH_DISABLE_ERRATA (1<< 4)
+#define DMA_IRQ_STATUS_ERRATA (1<< 5)
+
enum omap_dma_burst_mode {
OMAP_DMA_DATA_BURST_DIS = 0,
OMAP_DMA_DATA_BURST_4,
@@ -346,6 +354,7 @@ struct omap_dma_dev_attr {
struct omap_system_dma_plat_info {
struct omap_dma_dev_attr *dma_attr;
void __iomem *omap_dma_base;
+ u32 errata;
};
extern void omap_set_dma_priority(int lch, int dst_port, int priority);
--
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