[U-Boot] [PATCH] tegra2: Use new GPIO APIs in gpio_config_uart()
... rather than open-coding the register accesses.
However, gpio_request() typically stores the "label" parameter in a global data structure. This causes problems when called from gpio_config_uart(), since the code is running before relocation. To solve this, pass a NULL string to gpio_request(), and modify gpio_request() not to touch the string if it's NULL.
Signed-off-by: Stephen Warren swarren@nvidia.com --- I tested this on Seaboard. With the code in the patch below, the UART works. If I comment out the body of gpio_config_uart_seaboard(), the UART does not work.
This patch should work with ToT U-Boot, but the context relies on the rename of gpio_config_uart() to gpio_config_uart_seaboard() contained in: http://patchwork.ozlabs.org/patch/118144/
board/nvidia/seaboard/seaboard.c | 18 ++---------------- drivers/gpio/tegra2_gpio.c | 6 ++++-- 2 files changed, 6 insertions(+), 18 deletions(-)
diff --git a/board/nvidia/seaboard/seaboard.c b/board/nvidia/seaboard/seaboard.c index 260a56d..4492c28 100644 --- a/board/nvidia/seaboard/seaboard.c +++ b/board/nvidia/seaboard/seaboard.c @@ -36,23 +36,9 @@ */ void gpio_config_uart_seaboard(void) { - int gp = GPIO_PI3; - struct gpio_ctlr *gpio = (struct gpio_ctlr *)NV_PA_GPIO_BASE; - struct gpio_ctlr_bank *bank = &gpio->gpio_bank[GPIO_BANK(gp)]; - u32 val; - /* Enable UART via GPIO_PI3 (port 8, bit 3) so serial console works */ - val = readl(&bank->gpio_config[GPIO_PORT(gp)]); - val |= 1 << GPIO_BIT(gp); - writel(val, &bank->gpio_config[GPIO_PORT(gp)]); - - val = readl(&bank->gpio_out[GPIO_PORT(gp)]); - val &= ~(1 << GPIO_BIT(gp)); - writel(val, &bank->gpio_out[GPIO_PORT(gp)]); - - val = readl(&bank->gpio_dir_out[GPIO_PORT(gp)]); - val |= 1 << GPIO_BIT(gp); - writel(val, &bank->gpio_dir_out[GPIO_PORT(gp)]); + gpio_request(GPIO_PI3, NULL); + gpio_direction_output(GPIO_PI3, 0); }
void gpio_config_uart(void) diff --git a/drivers/gpio/tegra2_gpio.c b/drivers/gpio/tegra2_gpio.c index f686e80..22669b6 100644 --- a/drivers/gpio/tegra2_gpio.c +++ b/drivers/gpio/tegra2_gpio.c @@ -146,8 +146,10 @@ int gpio_request(int gp, const char *label) if (gp >= MAX_NUM_GPIOS) return -1;
- strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE); - gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0'; + if (label != NULL) { + strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE); + gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0'; + }
/* Configure as a GPIO */ set_config(gp, 1);
Hi Stephen,
On Thu, Oct 6, 2011 at 3:52 PM, Stephen Warren swarren@nvidia.com wrote:
... rather than open-coding the register accesses.
However, gpio_request() typically stores the "label" parameter in a global data structure. This causes problems when called from gpio_config_uart(), since the code is running before relocation. To solve this, pass a NULL string to gpio_request(), and modify gpio_request() not to touch the string if it's NULL.
Signed-off-by: Stephen Warren swarren@nvidia.com
Acked-by: Simon Glass sjg@chromium.org Tested-by: Simon Glass sjg@chromium.org
I tested this on Seaboard. With the code in the patch below, the UART works. If I comment out the body of gpio_config_uart_seaboard(), the UART does not work.
This patch should work with ToT U-Boot, but the context relies on the rename of gpio_config_uart() to gpio_config_uart_seaboard() contained in: http://patchwork.ozlabs.org/patch/118144/
board/nvidia/seaboard/seaboard.c | 18 ++---------------- drivers/gpio/tegra2_gpio.c | 6 ++++-- 2 files changed, 6 insertions(+), 18 deletions(-)
diff --git a/board/nvidia/seaboard/seaboard.c b/board/nvidia/seaboard/seaboard.c index 260a56d..4492c28 100644 --- a/board/nvidia/seaboard/seaboard.c +++ b/board/nvidia/seaboard/seaboard.c @@ -36,23 +36,9 @@ */ void gpio_config_uart_seaboard(void) {
- int gp = GPIO_PI3;
- struct gpio_ctlr *gpio = (struct gpio_ctlr *)NV_PA_GPIO_BASE;
- struct gpio_ctlr_bank *bank = &gpio->gpio_bank[GPIO_BANK(gp)];
- u32 val;
/* Enable UART via GPIO_PI3 (port 8, bit 3) so serial console works */
- val = readl(&bank->gpio_config[GPIO_PORT(gp)]);
- val |= 1 << GPIO_BIT(gp);
- writel(val, &bank->gpio_config[GPIO_PORT(gp)]);
- val = readl(&bank->gpio_out[GPIO_PORT(gp)]);
- val &= ~(1 << GPIO_BIT(gp));
- writel(val, &bank->gpio_out[GPIO_PORT(gp)]);
- val = readl(&bank->gpio_dir_out[GPIO_PORT(gp)]);
- val |= 1 << GPIO_BIT(gp);
- writel(val, &bank->gpio_dir_out[GPIO_PORT(gp)]);
- gpio_request(GPIO_PI3, NULL);
- gpio_direction_output(GPIO_PI3, 0);
}
void gpio_config_uart(void) diff --git a/drivers/gpio/tegra2_gpio.c b/drivers/gpio/tegra2_gpio.c index f686e80..22669b6 100644 --- a/drivers/gpio/tegra2_gpio.c +++ b/drivers/gpio/tegra2_gpio.c @@ -146,8 +146,10 @@ int gpio_request(int gp, const char *label) if (gp >= MAX_NUM_GPIOS) return -1;
- strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE);
- gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0';
- if (label != NULL) {
- strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE);
- gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0';
- }
/* Configure as a GPIO */ set_config(gp, 1); -- 1.7.0.4
On 10/11/2011 06:07 PM, Simon Glass wrote:
Hi Stephen,
On Thu, Oct 6, 2011 at 3:52 PM, Stephen Warren swarren@nvidia.com wrote:
... rather than open-coding the register accesses.
However, gpio_request() typically stores the "label" parameter in a global data structure. This causes problems when called from gpio_config_uart(), since the code is running before relocation. To solve this, pass a NULL string to gpio_request(), and modify gpio_request() not to touch the string if it's NULL.
Signed-off-by: Stephen Warren swarren@nvidia.com
Acked-by: Simon Glass sjg@chromium.org Tested-by: Simon Glass sjg@chromium.org
Albert, sorry I forgot to CC you on my original patch submission. Can you please also consider this patch. Thanks.
I tested this on Seaboard. With the code in the patch below, the UART works. If I comment out the body of gpio_config_uart_seaboard(), the UART does not work.
This patch should work with ToT U-Boot, but the context relies on the rename of gpio_config_uart() to gpio_config_uart_seaboard() contained in: http://patchwork.ozlabs.org/patch/118144/
board/nvidia/seaboard/seaboard.c | 18 ++---------------- drivers/gpio/tegra2_gpio.c | 6 ++++-- 2 files changed, 6 insertions(+), 18 deletions(-)
diff --git a/board/nvidia/seaboard/seaboard.c b/board/nvidia/seaboard/seaboard.c index 260a56d..4492c28 100644 --- a/board/nvidia/seaboard/seaboard.c +++ b/board/nvidia/seaboard/seaboard.c @@ -36,23 +36,9 @@ */ void gpio_config_uart_seaboard(void) {
int gp = GPIO_PI3;struct gpio_ctlr *gpio = (struct gpio_ctlr *)NV_PA_GPIO_BASE;struct gpio_ctlr_bank *bank = &gpio->gpio_bank[GPIO_BANK(gp)];u32 val;/* Enable UART via GPIO_PI3 (port 8, bit 3) so serial console works */val = readl(&bank->gpio_config[GPIO_PORT(gp)]);val |= 1 << GPIO_BIT(gp);writel(val, &bank->gpio_config[GPIO_PORT(gp)]);val = readl(&bank->gpio_out[GPIO_PORT(gp)]);val &= ~(1 << GPIO_BIT(gp));writel(val, &bank->gpio_out[GPIO_PORT(gp)]);val = readl(&bank->gpio_dir_out[GPIO_PORT(gp)]);val |= 1 << GPIO_BIT(gp);writel(val, &bank->gpio_dir_out[GPIO_PORT(gp)]);
gpio_request(GPIO_PI3, NULL);gpio_direction_output(GPIO_PI3, 0);}
void gpio_config_uart(void) diff --git a/drivers/gpio/tegra2_gpio.c b/drivers/gpio/tegra2_gpio.c index f686e80..22669b6 100644 --- a/drivers/gpio/tegra2_gpio.c +++ b/drivers/gpio/tegra2_gpio.c @@ -146,8 +146,10 @@ int gpio_request(int gp, const char *label) if (gp >= MAX_NUM_GPIOS) return -1;
strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE);gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0';
if (label != NULL) {strncpy(gpio_names[gp].name, label, GPIO_NAME_SIZE);gpio_names[gp].name[GPIO_NAME_SIZE - 1] = '\0';} /* Configure as a GPIO */ set_config(gp, 1);-- 1.7.0.4
Hi Stephen,
On Thu, 6 Oct 2011 16:52:22 -0600 Stephen Warren swarren@nvidia.com wrote:
... rather than open-coding the register accesses.
However, gpio_request() typically stores the "label" parameter in a global data structure. This causes problems when called from gpio_config_uart(), since the code is running before relocation. To solve this, pass a NULL string to gpio_request(), and modify gpio_request() not to touch the string if it's NULL.
Signed-off-by: Stephen Warren swarren@nvidia.com
I tested this on Seaboard. With the code in the patch below, the UART works. If I comment out the body of gpio_config_uart_seaboard(), the UART does not work.
This patch should work with ToT U-Boot, but the context relies on the rename of gpio_config_uart() to gpio_config_uart_seaboard() contained in: http://patchwork.ozlabs.org/patch/118144/
board/nvidia/seaboard/seaboard.c | 18 ++---------------- drivers/gpio/tegra2_gpio.c | 6 ++++-- 2 files changed, 6 insertions(+), 18 deletions(-)
This patch doesn't apply cleanly. There were a lot of tegra2 patches, so I'm not sure if it is not superseded by some newer patches. Can you please check and if the patch is needed, then re-base and resubmit. Thanks!
Anatolij
Anatolij Gustschin wrote at Thursday, December 01, 2011 4:09 PM:
On Thu, 6 Oct 2011 16:52:22 -0600 Stephen Warren swarren@nvidia.com wrote:
... rather than open-coding the register accesses.
However, gpio_request() typically stores the "label" parameter in a global data structure. This causes problems when called from gpio_config_uart(), since the code is running before relocation. To solve this, pass a NULL string to gpio_request(), and modify gpio_request() not to touch the string
...
This patch doesn't apply cleanly. There were a lot of tegra2 patches, so I'm not sure if it is not superseded by some newer patches. Can you please check and if the patch is needed, then re-base and resubmit. Thanks!
Yes, there are a lot of Tegra patches outstanding, and they need to be applied in a specific order. Tom Warren just got set up to create a u-boot-tegra.git and handle all the merging, so I think you can ignore this patch for now.
Thanks for taking a look though!
participants (3)
-
Anatolij Gustschin -
Simon Glass -
Stephen Warren