Re: [PATCH v4 3/4] venus: firmware: add no TZ boot and shutdown routine

[Stanimir Varbanov]

Hi Vikash,

On 08/06/2018 04:28 PM, Vikash Garodia wrote:
> Video hardware is mainly comprised of vcodec subsystem and video
> control subsystem. Video control has ARM9 which executes the video
> firmware instructions whereas vcodec does the video frame processing.
> This change adds support to load the video firmware and bring ARM9
> out of reset for platforms which does not have trustzone.
> 
> Signed-off-by: Vikash Garodia <vgarodia@xxxxxxxxxxxxxx>
> ---
>  drivers/media/platform/qcom/venus/core.c         |  6 +-
>  drivers/media/platform/qcom/venus/core.h         |  6 ++
>  drivers/media/platform/qcom/venus/firmware.c     | 91 +++++++++++++++++++++++-
>  drivers/media/platform/qcom/venus/firmware.h     |  2 +-
>  drivers/media/platform/qcom/venus/hfi_venus_io.h |  1 +
>  5 files changed, 99 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
> index 75b9785..393994e 100644
> --- a/drivers/media/platform/qcom/venus/core.c
> +++ b/drivers/media/platform/qcom/venus/core.c
> @@ -76,7 +76,7 @@ static void venus_sys_error_handler(struct work_struct *work)
>  	hfi_core_deinit(core, true);
>  	hfi_destroy(core);
>  	mutex_lock(&core->lock);
> -	venus_shutdown(core->dev);
> +	venus_shutdown(core);
>  
>  	pm_runtime_put_sync(core->dev);
>  
> @@ -323,7 +323,7 @@ static int venus_probe(struct platform_device *pdev)
>  err_core_deinit:
>  	hfi_core_deinit(core, false);
>  err_venus_shutdown:
> -	venus_shutdown(dev);
> +	venus_shutdown(core);
>  err_runtime_disable:
>  	pm_runtime_set_suspended(dev);
>  	pm_runtime_disable(dev);
> @@ -344,7 +344,7 @@ static int venus_remove(struct platform_device *pdev)
>  	WARN_ON(ret);
>  
>  	hfi_destroy(core);
> -	venus_shutdown(dev);
> +	venus_shutdown(core);
>  	of_platform_depopulate(dev);
>  
>  	pm_runtime_put_sync(dev);
> diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
> index eb5ee66..8c64177 100644
> --- a/drivers/media/platform/qcom/venus/core.h
> +++ b/drivers/media/platform/qcom/venus/core.h
> @@ -81,6 +81,11 @@ struct venus_caps {
>  	bool valid;	/* used only for Venus v1xx */
>  };
>  
> +struct video_firmware {
> +	struct device *dev;
> +	struct iommu_domain *iommu_domain;
> +};
> +
>  /**
>   * struct venus_core - holds core parameters valid for all instances
>   *
> @@ -129,6 +134,7 @@ struct venus_core {
>  	struct device *dev;
>  	struct device *dev_dec;
>  	struct device *dev_enc;
> +	struct video_firmware fw;
>  	bool no_tz;
>  	struct mutex lock;
>  	struct list_head instances;
> diff --git a/drivers/media/platform/qcom/venus/firmware.c b/drivers/media/platform/qcom/venus/firmware.c
> index 4577043..30130d4 100644
> --- a/drivers/media/platform/qcom/venus/firmware.c
> +++ b/drivers/media/platform/qcom/venus/firmware.c
> @@ -12,8 +12,10 @@
>   *
>   */
>  
> +#include <linux/platform_device.h>

please keep includes alphabetically ordered.

>  #include <linux/device.h>
>  #include <linux/firmware.h>
> +#include <linux/iommu.h>

and here too

>  #include <linux/kernel.h>
>  #include <linux/io.h>
>  #include <linux/of.h>
> @@ -118,6 +120,76 @@ static int venus_load_fw(struct venus_core *core, const char *fwname,
>  	return ret;
>  }
>  
> +static int venus_boot_no_tz(struct venus_core *core, phys_addr_t mem_phys,
> +			size_t mem_size)
> +{
> +	struct iommu_domain *iommu_dom;
> +	struct device *dev;
> +	int ret;
> +
> +	dev = core->fw.dev;
> +	if (!dev)
> +		return -EPROBE_DEFER;
> +
> +	iommu_dom = iommu_domain_alloc(&platform_bus_type);
> +	if (!iommu_dom) {
> +		dev_err(dev, "Failed to allocate iommu domain\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = iommu_attach_device(iommu_dom, dev);
> +	if (ret) {
> +		dev_err(dev, "could not attach device\n");
> +		goto err_attach;
> +	}
> +
> +	ret = iommu_map(iommu_dom, VENUS_FW_START_ADDR, mem_phys, mem_size,
> +			IOMMU_READ | IOMMU_WRITE | IOMMU_PRIV);
> +	if (ret) {
> +		dev_err(dev, "could not map video firmware region\n");
> +		goto err_map;
> +	}
> +
> +	core->fw.iommu_domain = iommu_dom;
> +	venus_reset_cpu(core);
> +
> +	return 0;
> +
> +err_map:
> +	iommu_detach_device(iommu_dom, dev);
> +err_attach:
> +	iommu_domain_free(iommu_dom);
> +	return ret;
> +}
> +
> +static int venus_shutdown_no_tz(struct venus_core *core)
> +{
> +	struct iommu_domain *iommu;
> +	size_t unmapped = 0;

no need to initialize unmapped variable.

> +	u32 reg;
> +	struct device *dev = core->fw.dev;

could you move longer lines at the beginning of the function

> +	void __iomem *reg_base = core->base;

renaming reg_base to base will give you shorter line(s), otherwise I
think you should use core->base directly

> +
> +	/* Assert the reset to ARM9 */
> +	reg = readl_relaxed(reg_base + WRAPPER_A9SS_SW_RESET);
> +	reg |= WRAPPER_A9SS_SW_RESET_BIT;
> +	writel_relaxed(reg, reg_base + WRAPPER_A9SS_SW_RESET);
> +
> +	/* Make sure reset is asserted before the mapping is removed */
> +	mb();
> +
> +	iommu = core->fw.iommu_domain;
> +
> +	unmapped = iommu_unmap(iommu, VENUS_FW_START_ADDR, VENUS_FW_MEM_SIZE);
> +	if (unmapped != VENUS_FW_MEM_SIZE)
> +		dev_err(dev, "failed to unmap firmware\n");
> +
> +	iommu_detach_device(iommu, dev);
> +	iommu_domain_free(iommu);
> +

the function doesn't return error why don't make it to return void? Up
to you.

> +	return 0;
> +}

-- 
regards,
Stan