Re: [PATCH] venus: core: add support to dump FW region

[Stanimir Varbanov]

On 11/30/20 7:36 AM, Dikshita Agarwal wrote:
> Add support to dump video FW region during FW crash
> using devcoredump helpers.
> 
> Signed-off-by: Dikshita Agarwal <dikshita@xxxxxxxxxxxxxx>
> ---
>  drivers/media/platform/qcom/venus/core.c | 47 ++++++++++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 
> diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
> index 6103aaf..01a0cfe 100644
> --- a/drivers/media/platform/qcom/venus/core.c
> +++ b/drivers/media/platform/qcom/venus/core.c
> @@ -7,8 +7,10 @@
>  #include <linux/interconnect.h>
>  #include <linux/ioctl.h>
>  #include <linux/delay.h>
> +#include <linux/devcoredump.h>
>  #include <linux/list.h>
>  #include <linux/module.h>
> +#include <linux/of_address.h>
>  #include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/slab.h>
> @@ -22,6 +24,48 @@
>  #include "firmware.h"
>  #include "pm_helpers.h"
>  
> +static int subsystem_dump(struct venus_core *core)

this function could return void because we don't handle the error in
venus_sys_error_handler().

> +{
> +	struct device_node *node;
> +	struct device *dev;
> +	struct resource r;
> +	void *mem_va;
> +	size_t mem_size;
> +	void *data;
> +	int ret;
> +
> +	dev = core->dev;
> +	node = of_parse_phandle(dev->of_node, "memory-region", 0);
> +	if (!node)
> +		return -EINVAL;
> +
> +	ret = of_address_to_resource(node, 0, &r);
> +	if (ret)
> +		goto err_put_node;
> +
> +	mem_size = resource_size(&r);

could you reuse the resource from venus_load_fw by adding r.sart and
resource size in venus_core->fw{} structure.

> +
> +	mem_va = memremap(r.start, mem_size, MEMREMAP_WC);
> +	if (!mem_va) {
> +		ret = -ENOMEM;
> +		goto err_put_node;
> +	}
> +
> +	data = vmalloc(mem_size);
> +	if (!data) {
> +		ret = -EINVAL;
> +		goto err_unmap;
> +	}
> +
> +	memcpy(data, mem_va, mem_size);
> +
> +	dev_coredumpv(dev, data, mem_size, GFP_KERNEL);
> +err_unmap:
> +	memunmap(mem_va);
> +err_put_node:
> +	of_node_put(node);
> +	return ret;
> +}
>  static void venus_event_notify(struct venus_core *core, u32 event)
>  {
>  	struct venus_inst *inst;
> @@ -67,6 +111,9 @@ static void venus_sys_error_handler(struct work_struct *work)
>  
>  	venus_shutdown(core);
>  
> +	dev_warn(core->dev, "dumping FW region!\n");

this warn is not needed, please drop it.

> +	subsystem_dump(core);

Are we sure that the dump is always required?

> +
>  	pm_runtime_put_sync(core->dev);
>  
>  	while (core->pmdomains[0] && pm_runtime_active(core->pmdomains[0]))
> 

-- 
regards,
Stan