Re: [PATCH 1/4] soc: qcom: mdt_loader: Add check to make scm calls

[Jordan Crouse <jcrouse@codeaurora.org>]

On Thu, May 17, 2018 at 05:02:17PM +0530, Vikash Garodia wrote:
> In order to invoke scm calls, ensure that the platform
> has the required support to invoke the scm calls in
> secure world.
> 
> Signed-off-by: Vikash Garodia <vgarodia@codeaurora.org>
> ---
>  drivers/soc/qcom/mdt_loader.c | 21 +++++++++++++--------
>  1 file changed, 13 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
> index 17b314d..db55d53 100644
> --- a/drivers/soc/qcom/mdt_loader.c
> +++ b/drivers/soc/qcom/mdt_loader.c
> @@ -121,10 +121,12 @@ int qcom_mdt_load(struct device *dev, const struct firmware *fw,
>  	if (!fw_name)
>  		return -ENOMEM;
>  
> -	ret = qcom_scm_pas_init_image(pas_id, fw->data, fw->size);
> -	if (ret) {
> -		dev_err(dev, "invalid firmware metadata\n");
> -		goto out;
> +	if (qcom_scm_is_available()) {
> +		ret = qcom_scm_pas_init_image(pas_id, fw->data, fw->size);
> +		if (ret) {
> +			dev_err(dev, "invalid firmware metadata\n");
> +			goto out;
> +		}
>  	}
>
>  	for (i = 0; i < ehdr->e_phnum; i++) {
> @@ -144,10 +146,13 @@ int qcom_mdt_load(struct device *dev, const struct firmware *fw,
>  	}
>  
>  	if (relocate) {
> -		ret = qcom_scm_pas_mem_setup(pas_id, mem_phys, max_addr - min_addr);
> -		if (ret) {
> -			dev_err(dev, "unable to setup relocation\n");
> -			goto out;
> +		if (qcom_scm_is_available()) {
> +			ret = qcom_scm_pas_mem_setup(pas_id, mem_phys,
> +							max_addr - min_addr);
> +			if (ret) {
> +				dev_err(dev, "unable to setup relocation\n");
> +				goto out;
> +			}
>  		}
>  

As far as I can tell you can make it all the way through the function with
'ret' uninitialized if qcom_scm_is_available() returns false which is a bug, but
I'm confused why you would even bother loading the firmware even if you didn't
have SCM.

Jordan

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