Re: [PATCH 06/11] usb: dwc2/gadget: ensure that all fifos have correct memory buffers

From: Marek Szyprowski
Date: Tue Jun 24 2014 - 01:50:13 EST


Hello,

On 2014-06-23 20:40, Paul Zimmerman wrote:
From: Robert Baldyga [mailto:r.baldyga@xxxxxxxxxxx]
Sent: Monday, June 23, 2014 12:51 AM

From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

Print warning if FIFOs are configured in such a way that they don't fit
into the SPRAM available on the s3c hsotg module.

Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
---
drivers/usb/dwc2/core.h | 1 +
drivers/usb/dwc2/gadget.c | 15 ++++++++++-----
2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 1efd10c..067390e 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -194,6 +194,7 @@ struct s3c_hsotg {
struct regulator_bulk_data supplies[ARRAY_SIZE(s3c_hsotg_supply_names)];

u32 phyif;
+ int fifo_mem;
unsigned int dedicated_fifos:1;
unsigned char num_of_eps;

diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
index 95b6dcb..21d21de 100644
--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -194,6 +194,8 @@ static void s3c_hsotg_init_fifo(struct s3c_hsotg *hsotg)
for (ep = 1; ep <= 15; ep++) {
val = addr;
val |= size << FIFOSIZE_DEPTH_SHIFT;
+ WARN_ONCE(addr + size > hsotg->fifo_mem,
+ "insufficient fifo memory");
addr += size;

writel(val, hsotg->regs + DPTXFSIZN(ep));
@@ -3030,19 +3032,22 @@ static void s3c_hsotg_initep(struct s3c_hsotg *hsotg,
*/
static void s3c_hsotg_hw_cfg(struct s3c_hsotg *hsotg)
{
- u32 cfg2, cfg4;
+ u32 cfg2, cfg3, cfg4;
/* check hardware configuration */

cfg2 = readl(hsotg->regs + 0x48);
hsotg->num_of_eps = (cfg2 >> 10) & 0xF;

- dev_info(hsotg->dev, "EPs:%d\n", hsotg->num_of_eps);
+ cfg3 = readl(hsotg->regs + 0x4C);
+ hsotg->fifo_mem = (cfg3 >> 16);

cfg4 = readl(hsotg->regs + 0x50);
hsotg->dedicated_fifos = (cfg4 >> 25) & 1;

- dev_info(hsotg->dev, "%s fifos\n",
- hsotg->dedicated_fifos ? "dedicated" : "shared");
+ dev_info(hsotg->dev, "EPs: %d, %s fifos, %d entries in SPRAM\n",
+ hsotg->num_of_eps,
+ hsotg->dedicated_fifos ? "dedicated" : "shared",
+ hsotg->fifo_mem);
}

/**
@@ -3495,8 +3500,8 @@ static int s3c_hsotg_probe(struct platform_device *pdev)
s3c_hsotg_phy_enable(hsotg);

s3c_hsotg_corereset(hsotg);
- s3c_hsotg_init(hsotg);
s3c_hsotg_hw_cfg(hsotg);
+ s3c_hsotg_init(hsotg);
This last hunk looks like it is not related to the rest of the patch? If
so, I think it should be a separate patch.

s3c_hsotg_hw_cfg() only reads hw configuration and some values read there (fifo_mem)
are used in s3c_hsotg_init_fifo(), which is called from s3c_hsotg_init(). This chunk
really belongs to this patch, although it might not be easy to notice it at the first
glance.

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland

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