Re: [Intel-gfx] [PATCH] drm/i915/bios: add helper for reading SPI

[Jani Nikula <jani.nikula@intel.com>]

On Fri, 12 May 2023, Rodrigo Vivi <rodrigo.vivi@kernel.org> wrote:
> On Fri, May 12, 2023 at 02:14:46PM +0300, Jani Nikula wrote:
>> Add helper for reading SPI to not duplicate the write&read combo
>> everywhere.
>> 
>> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>
> BAT failure is likely a false positive on crcs... this patch
> looks correct to me without any functional change.

Re-test passed bat.

> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Thanks, pushed to din.

BR,
Jani.

>
>
>> ---
>>  drivers/gpu/drm/i915/display/intel_bios.c | 23 ++++++++++++-----------
>>  1 file changed, 12 insertions(+), 11 deletions(-)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
>> index 64eb11a45265..34a397adbd6b 100644
>> --- a/drivers/gpu/drm/i915/display/intel_bios.c
>> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
>> @@ -3033,6 +3033,13 @@ bool intel_bios_is_valid_vbt(const void *buf, size_t size)
>>  	return vbt;
>>  }
>>  
>> +static u32 intel_spi_read(struct intel_uncore *uncore, u32 offset)
>> +{
>> +	intel_uncore_write(uncore, PRIMARY_SPI_ADDRESS, offset);
>> +
>> +	return intel_uncore_read(uncore, PRIMARY_SPI_TRIGGER);
>> +}
>> +
>>  static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
>>  {
>>  	u32 count, data, found, store = 0;
>> @@ -3049,9 +3056,7 @@ static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
>>  	oprom_offset &= OROM_OFFSET_MASK;
>>  
>>  	for (count = 0; count < oprom_size; count += 4) {
>> -		intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, oprom_offset + count);
>> -		data = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
>> -
>> +		data = intel_spi_read(&i915->uncore, oprom_offset + count);
>>  		if (data == *((const u32 *)"$VBT")) {
>>  			found = oprom_offset + count;
>>  			break;
>> @@ -3062,20 +3067,16 @@ static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
>>  		goto err_not_found;
>>  
>>  	/* Get VBT size and allocate space for the VBT */
>> -	intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, found +
>> -		   offsetof(struct vbt_header, vbt_size));
>> -	vbt_size = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
>> +	vbt_size = intel_spi_read(&i915->uncore,
>> +				  found + offsetof(struct vbt_header, vbt_size));
>>  	vbt_size &= 0xffff;
>>  
>>  	vbt = kzalloc(round_up(vbt_size, 4), GFP_KERNEL);
>>  	if (!vbt)
>>  		goto err_not_found;
>>  
>> -	for (count = 0; count < vbt_size; count += 4) {
>> -		intel_uncore_write(&i915->uncore, PRIMARY_SPI_ADDRESS, found + count);
>> -		data = intel_uncore_read(&i915->uncore, PRIMARY_SPI_TRIGGER);
>> -		*(vbt + store++) = data;
>> -	}
>> +	for (count = 0; count < vbt_size; count += 4)
>> +		*(vbt + store++) = intel_spi_read(&i915->uncore, found + count);
>>  
>>  	if (!intel_bios_is_valid_vbt(vbt, vbt_size))
>>  		goto err_free_vbt;
>> -- 
>> 2.39.2
>> 

-- 
Jani Nikula, Intel Open Source Graphics Center