Re: [RFC PATCH v3 05/16] ARM: edma: add AM33XX crossbar event support
From: Sekhar Nori <hidden>
Date: 2012-10-28 11:12:37
Also in:
linux-arm-kernel, linux-mmc, linux-omap, linux-spi, lkml
On 10/18/2012 6:56 PM, Matt Porter wrote:
quoted hunk ↗ jump to hunk
Adds support for the per-EDMA channel event mux. This is required for any peripherals using DMA crossbar mapped events. Signed-off-by: Matt Porter <redacted> --- arch/arm/common/edma.c | 63 +++++++++++++++++++++++++++++++++++- include/linux/platform_data/edma.h | 1 + 2 files changed, 63 insertions(+), 1 deletion(-)diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c index 6d2a590..b761b7a 100644 --- a/arch/arm/common/edma.c +++ b/arch/arm/common/edma.c@@ -1425,6 +1425,53 @@ static int edma_of_read_u32_to_s16_array(const struct device_node *np, return 0; } +static int edma_xbar_event_map(struct device *dev, + struct device_node *node, + struct edma_soc_info *pdata, int len) +{ + int ret = 0; + int i; + struct resource res; + void *xbar; + s16 (*xbar_chans)[2]; + u32 shift, offset, mux; + + xbar_chans = devm_kzalloc(dev, + len/sizeof(s16) + 2*sizeof(s16), + GFP_KERNEL); + if (!xbar_chans) + return -ENOMEM; + + ret = of_address_to_resource(node, 1, &res); + if (IS_ERR_VALUE(ret)) + return -EIO; + + xbar = devm_ioremap(dev, res.start, resource_size(&res)); + if (!xbar) + return -EIO;
-ENOMEM is more appropiate for ioremap failures.
+
+ ret = edma_of_read_u32_to_s16_array(node,
+ "ti,edma-xbar-event-map",
+ (s16 *)xbar_chans,
+ len/sizeof(u32));
+ if (IS_ERR_VALUE(ret))
+ return -EIO;
+
+ for (i = 0; xbar_chans[i][0] != -1; i++) {
+ shift = (xbar_chans[i][1] % 4) * 8;
+ offset = xbar_chans[i][1] >> 2;
+ offset <<= 2;
+ mux = __raw_readl((void *)((u32)xbar + offset));Dont use __raw* variants of io accessors. There will be ordering issues on ARMv7.
+ mux &= (~(0xff << shift)); + mux |= (xbar_chans[i][0] << shift);
Unnecessary parens above.
quoted hunk ↗ jump to hunk
+ __raw_writel(mux, (void *)((u32)xbar + offset)); + } + + pdata->xbar_chans = xbar_chans; + + return 0; +} + static int edma_of_parse_dt(struct device *dev, struct device_node *node, struct edma_soc_info *pdata)@@ -1453,7 +1500,6 @@ static int edma_of_parse_dt(struct device *dev, pdata->n_slot = value; pdata->n_cc = 1; - /* This is unused */
The comment should have not been part of 4/16? Thanks, Sekhar