Re: [PATCH v2 1/3] ARM: da850: fix infinite loop in clk_set_rate()

2016-12-05 9:38 GMT+01:00 Sekhar Nori [off-list ref]:

On Friday 02 December 2016 09:08 PM, Bartosz Golaszewski wrote:

quoted

The aemif clock is added twice to the lookup table in da850.c. This
breaks the children list of pll0_sysclk3 as we're using the same list
links in struct clk. When calling clk_set_rate(), we get stuck in
propagate_rate().

Create a separate clock for nand, inheriting the rate of the aemif
clock and retrieve it in the davinci_nand module.

Signed-off-by: Bartosz Golaszewski <redacted>
---
 arch/arm/mach-davinci/da850.c   | 7 ++++++-
 drivers/mtd/nand/davinci_nand.c | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-davinci/da850.c b/arch/arm/mach-davinci/da850.c
index e770c97..1fcc986 100644
--- a/arch/arm/mach-davinci/da850.c
+++ b/arch/arm/mach-davinci/da850.c

@@ -367,6 +367,11 @@ static struct clk aemif_clk = {
      .flags          = ALWAYS_ENABLED,
 };

+static struct clk nand_clk = {
+     .name           = "nand",
+     .parent         = &aemif_clk,
+};
+
 static struct clk usb11_clk = {
      .name           = "usb11",
      .parent         = &pll0_sysclk4,

@@ -537,7 +542,7 @@ static struct clk_lookup da850_clks[] = {
      CLK("da830-mmc.0",      NULL,           &mmcsd0_clk),
      CLK("da830-mmc.1",      NULL,           &mmcsd1_clk),
      CLK("ti-aemif",         NULL,           &aemif_clk),
-     CLK(NULL,               "aemif",        &aemif_clk),
+     CLK(NULL,               "nand",         &nand_clk),

Why use a NULL device name here?

quoted

      CLK("ohci-da8xx",       "usb11",        &usb11_clk),
      CLK("musb-da8xx",       "usb20",        &usb20_clk),
      CLK("spi_davinci.0",    NULL,           &spi0_clk),

diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c
index 27fa8b8..5857d06 100644
--- a/drivers/mtd/nand/davinci_nand.c
+++ b/drivers/mtd/nand/davinci_nand.c

@@ -694,7 +694,7 @@ static int nand_davinci_probe(struct platform_device *pdev)

      ret = -EINVAL;

-     info->clk = devm_clk_get(&pdev->dev, "aemif");
+     info->clk = devm_clk_get(&pdev->dev, "nand");

This driver is used by keystone devices too. So just changing the
connection id will likely break them. Why do you need to change the
connection id?

Thanks,
Sekhar

Thanks, I didn't know it.

I thought it would make the purpose of the clock more obvious. I'll
change it back to "aemif".

Best regards,
Bartosz Golaszewski