Re: [PATCH] drm/amdgpu: fix sysfs ip base addr for 64bit in standalone mode

[Mario Limonciello <superm1@kernel.org>]

On 8/13/26 10:28, Alex Deucher wrote:
> On Thu, Aug 13, 2026 at 11:20 AM Mukul Joshi <mukul.joshi@amd.com> wrote:
>>
>> In standalone mode the ip_discovery sysfs tree is built from a verbatim
>> copy of the discovery binary taken before reg_base_init() collapses the
>> 64bit base addresses in place. Decoding as 32bit there yields interleaved
>> zeros. Decode base_address_64[] in that case; keep reading the already
>> collapsed adev->discovery.bin as-is otherwise.
>>
>> Fixes: 3ee1065e9830 ("drm/amdgpu: Export ip_discovery sysfs on probe failure")
>> Signed-off-by: Mukul Joshi <mukul.joshi@amd.com>
> 
> Acked-by: Alex Deucher <alexander.deucher@amd.com>

Cc: stable@vger.kernel.org
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>

> 
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 15 +++++++++++++--
>>   1 file changed, 13 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
>> index b5bc0d71653d..8745b0a66f1d 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
>> @@ -1308,8 +1308,19 @@ static int amdgpu_discovery_sysfs_ips(struct amdgpu_device *adev,
>>                                          ip_hw_instance->num_instance);
>>                          ip_hw_instance->num_base_addresses = ip->num_base_address;
>>
>> -                       for (kk = 0; kk < ip_hw_instance->num_base_addresses; kk++)
>> -                               ip_hw_instance->base_addr[kk] = ip->base_address[kk];
>> +                       for (kk = 0; kk < ip_hw_instance->num_base_addresses; kk++) {
>> +                               /*
>> +                                * Standalone mode uses a raw copy of the discovery
>> +                                * binary; decode 64-bit addresses here. The shared
>> +                                * bin is already collapsed to 32-bit in place.
>> +                                */
>> +                               if (reg_base_64 && ip_top->standalone_mode)
>> +                                       ip_hw_instance->base_addr[kk] =
>> +                                               lower_32_bits(le64_to_cpu(ip->base_address_64[kk])) & 0x3FFFFFFF;
>> +                               else
>> +                                       ip_hw_instance->base_addr[kk] =
>> +                                               le32_to_cpu(ip->base_address[kk]);
>> +                       }
>>
>>                          kobject_init(&ip_hw_instance->kobj, &ip_hw_instance_ktype);
>>                          ip_hw_instance->kobj.kset = &ip_hw_id->hw_id_kset;
>> --
>> 2.54.0
>>