Re: [PATCH 1/4] venus: firmware: check fw size against DT memory region size

[Stanimir Varbanov]

Hi Alex,

Thanks for the review!

On 1/23/19 8:10 AM, Alexandre Courbot wrote:
> Sorry for the delayed review! >_<
> 
> On Wed, Jan 9, 2019 at 5:46 PM Stanimir Varbanov
> <stanimir.varbanov@xxxxxxxxxx> wrote:
>>
>> By historical reasons we defined firmware memory size to be 6MB even
>> that the firmware size for all supported Venus versions is 5MBs. Correct
>> that by compare the required firmware size returned from mdt loader and
>> the one provided by DT reserved memory region. We proceed further if the
>> required firmware size is smaller than provided by DT memory region.
>>
>> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx>
>> ---
>>  drivers/media/platform/qcom/venus/core.h     |  1 +
>>  drivers/media/platform/qcom/venus/firmware.c | 54 +++++++++++---------
>>  2 files changed, 31 insertions(+), 24 deletions(-)
>>
>> diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
>> index 6382cea29185..79c7e816c706 100644
>> --- a/drivers/media/platform/qcom/venus/core.h
>> +++ b/drivers/media/platform/qcom/venus/core.h
>> @@ -134,6 +134,7 @@ struct venus_core {
>>         struct video_firmware {
>>                 struct device *dev;
>>                 struct iommu_domain *iommu_domain;
>> +               size_t mapped_mem_size;
>>         } fw;
>>         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 c29acfd70c1b..6b509ffd022a 100644
>> --- a/drivers/media/platform/qcom/venus/firmware.c
>> +++ b/drivers/media/platform/qcom/venus/firmware.c
>> @@ -35,14 +35,15 @@
>>
>>  static void venus_reset_cpu(struct venus_core *core)
>>  {
>> +       u32 fw_size = core->fw.mapped_mem_size;
>>         void __iomem *base = core->base;
>>
>>         writel(0, base + WRAPPER_FW_START_ADDR);
>> -       writel(VENUS_FW_MEM_SIZE, base + WRAPPER_FW_END_ADDR);
>> +       writel(fw_size, base + WRAPPER_FW_END_ADDR);
>>         writel(0, base + WRAPPER_CPA_START_ADDR);
>> -       writel(VENUS_FW_MEM_SIZE, base + WRAPPER_CPA_END_ADDR);
>> -       writel(VENUS_FW_MEM_SIZE, base + WRAPPER_NONPIX_START_ADDR);
>> -       writel(VENUS_FW_MEM_SIZE, base + WRAPPER_NONPIX_END_ADDR);
>> +       writel(fw_size, base + WRAPPER_CPA_END_ADDR);
>> +       writel(fw_size, base + WRAPPER_NONPIX_START_ADDR);
>> +       writel(fw_size, base + WRAPPER_NONPIX_END_ADDR);
>>         writel(0x0, base + WRAPPER_CPU_CGC_DIS);
>>         writel(0x0, base + WRAPPER_CPU_CLOCK_CONFIG);
>>
>> @@ -74,6 +75,9 @@ static int venus_load_fw(struct venus_core *core, const char *fwname,
>>         void *mem_va;
>>         int ret;
>>
>> +       *mem_phys = 0;
>> +       *mem_size = 0;
>> +
>>         dev = core->dev;
>>         node = of_parse_phandle(dev->of_node, "memory-region", 0);
>>         if (!node) {
>> @@ -85,28 +89,30 @@ static int venus_load_fw(struct venus_core *core, const char *fwname,
>>         if (ret)
>>                 return ret;
>>
>> +       ret = request_firmware(&mdt, fwname, dev);
>> +       if (ret < 0)
>> +               return ret;
>> +
>> +       fw_size = qcom_mdt_get_size(mdt);
>> +       if (fw_size < 0) {
>> +               ret = fw_size;
>> +               goto err_release_fw;
>> +       }
>> +
>>         *mem_phys = r.start;
>>         *mem_size = resource_size(&r);
>>
>> -       if (*mem_size < VENUS_FW_MEM_SIZE)
>> -               return -EINVAL;
>> +       if (*mem_size < fw_size || fw_size > VENUS_FW_MEM_SIZE) {
> 
> Do we still need to check for fw_size > VENUS_FW_MEM_SIZE ? If we
> don't then we can remove the definition of VENUS_FW_MEM_SIZE
> altogether.

I know, it is a bit paranoid but I'd want to avoid if someone set
unreasonable memory size. So I'd like to have some sanitized firmware
region size in the driver.

> 
>> +               ret = -EINVAL;
>> +               goto err_release_fw;
>> +       }
>>
>>         mem_va = memremap(r.start, *mem_size, MEMREMAP_WC);
>>         if (!mem_va) {
>>                 dev_err(dev, "unable to map memory region: %pa+%zx\n",
>>                         &r.start, *mem_size);
>> -               return -ENOMEM;
>> -       }
>> -
>> -       ret = request_firmware(&mdt, fwname, dev);
>> -       if (ret < 0)
>> -               goto err_unmap;
>> -
>> -       fw_size = qcom_mdt_get_size(mdt);
>> -       if (fw_size < 0) {
>> -               ret = fw_size;
>> -               release_firmware(mdt);
>> -               goto err_unmap;
>> +               ret = -ENOMEM;
>> +               goto err_release_fw;
>>         }
>>
>>         if (core->use_tz)
>> @@ -116,10 +122,9 @@ static int venus_load_fw(struct venus_core *core, const char *fwname,
>>                 ret = qcom_mdt_load_no_init(dev, mdt, fwname, VENUS_PAS_ID,
>>                                             mem_va, *mem_phys, *mem_size, NULL);
>>
>> -       release_firmware(mdt);
>> -
>> -err_unmap:
>>         memunmap(mem_va);
>> +err_release_fw:
>> +       release_firmware(mdt);
>>         return ret;
>>  }
>>
>> @@ -135,6 +140,7 @@ static int venus_boot_no_tz(struct venus_core *core, phys_addr_t mem_phys,
>>                 return -EPROBE_DEFER;
>>
>>         iommu = core->fw.iommu_domain;
>> +       core->fw.mapped_mem_size = mem_size;
>>
>>         ret = iommu_map(iommu, VENUS_FW_START_ADDR, mem_phys, mem_size,
>>                         IOMMU_READ | IOMMU_WRITE | IOMMU_PRIV);
>> @@ -151,7 +157,7 @@ static int venus_boot_no_tz(struct venus_core *core, phys_addr_t mem_phys,
>>  static int venus_shutdown_no_tz(struct venus_core *core)
>>  {
>>         struct iommu_domain *iommu;
>> -       size_t unmapped;
>> +       size_t unmapped, mapped = core->fw.mapped_mem_size;
> 
> mapped should probably be const here.

Ok.

> 
> With these minor comments:
> 
> Reviewed-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> Tested-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> 
> For the 4 patches in this series. I could see the improvement in
> decoder performance introduced by patches 2 and 3, thanks!
> 

-- 
regards,
Stan