Suspend will disable pcie device. Thus, resume should do full hw
initialization again.
Add some APIs to ast_drm_thaw() before ast_post_gpu() to fix the issue.

Fixes: 5b71707dd13 ("drm/ast: Enable and unlock device access early during init")
Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
---
 drivers/gpu/drm/ast/ast_drv.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
index f8c49ba68e78..45a9c7bf49c8 100644
--- a/drivers/gpu/drm/ast/ast_drv.c
+++ b/drivers/gpu/drm/ast/ast_drv.c
@@ -391,6 +391,11 @@ static int ast_drm_freeze(struct drm_device *dev)
 
 static int ast_drm_thaw(struct drm_device *dev)
 {
+	struct ast_device *ast = to_ast_device(dev);
+
+	ast_enable_vga(ioregs);
+	ast_open_key(ioregs);
+	ast_enable_mmio(dev, ioregs);
 	ast_post_gpu(dev);
 
 	return drm_mode_config_helper_resume(dev);

base-commit: e9d22f7a6655941fc8b2b942ed354ec780936b3e
prerequisite-patch-id: a03a33902f33bcc38091e2cdce9d79f630464c30
prerequisite-patch-id: 505779a1e2094f2ee2f2a55ad44aac5cd1d5342f
-- 
2.25.1

(Cary, this looks like it fixes the problem you reported.)

Hi Jammy

Am 18.07.24 um 05:03 schrieb Jammy Huang:
> Suspend will disable pcie device. Thus, resume should do full hw
> initialization again.
> Add some APIs to ast_drm_thaw() before ast_post_gpu() to fix the issue.
>
> Fixes: 5b71707dd13 ("drm/ast: Enable and unlock device access early during init")
> Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

Thanks a lot for this fix.

Best regards
Thomas

> ---
>   drivers/gpu/drm/ast/ast_drv.c | 5 +++++
>   1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
> index f8c49ba68e78..45a9c7bf49c8 100644
> --- a/drivers/gpu/drm/ast/ast_drv.c
> +++ b/drivers/gpu/drm/ast/ast_drv.c
> @@ -391,6 +391,11 @@ static int ast_drm_freeze(struct drm_device *dev)
>   
>   static int ast_drm_thaw(struct drm_device *dev)
>   {
> +	struct ast_device *ast = to_ast_device(dev);
> +
> +	ast_enable_vga(ioregs);
> +	ast_open_key(ioregs);
> +	ast_enable_mmio(dev, ioregs);
>   	ast_post_gpu(dev);
>   
>   	return drm_mode_config_helper_resume(dev);
>
> base-commit: e9d22f7a6655941fc8b2b942ed354ec780936b3e
> prerequisite-patch-id: a03a33902f33bcc38091e2cdce9d79f630464c30
> prerequisite-patch-id: 505779a1e2094f2ee2f2a55ad44aac5cd1d5342f

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)

Am 18.07.24 um 08:50 schrieb Thomas Zimmermann:
> (Cary, this looks like it fixes the problem you reported.)
>
> Hi Jammy
>
> Am 18.07.24 um 05:03 schrieb Jammy Huang:
>> Suspend will disable pcie device. Thus, resume should do full hw
>> initialization again.
>> Add some APIs to ast_drm_thaw() before ast_post_gpu() to fix the issue.
>>
>> Fixes: 5b71707dd13 ("drm/ast: Enable and unlock device access early 
>> during init")
>> Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
>
> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
>
> Thanks a lot for this fix.
>
> Best regards
> Thomas
>
>> ---
>>   drivers/gpu/drm/ast/ast_drv.c | 5 +++++
>>   1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/ast/ast_drv.c 
>> b/drivers/gpu/drm/ast/ast_drv.c
>> index f8c49ba68e78..45a9c7bf49c8 100644
>> --- a/drivers/gpu/drm/ast/ast_drv.c
>> +++ b/drivers/gpu/drm/ast/ast_drv.c
>> @@ -391,6 +391,11 @@ static int ast_drm_freeze(struct drm_device *dev)
>>     static int ast_drm_thaw(struct drm_device *dev)
>>   {
>> +    struct ast_device *ast = to_ast_device(dev);
>> +
>> +    ast_enable_vga(ioregs);
>> +    ast_open_key(ioregs);
>> +    ast_enable_mmio(dev, ioregs);

BTW I got a build error. I'll fix that up before committing the patch.

Best regards
Thomas

>>       ast_post_gpu(dev);
>>         return drm_mode_config_helper_resume(dev);
>>
>> base-commit: e9d22f7a6655941fc8b2b942ed354ec780936b3e
>> prerequisite-patch-id: a03a33902f33bcc38091e2cdce9d79f630464c30
>> prerequisite-patch-id: 505779a1e2094f2ee2f2a55ad44aac5cd1d5342f
>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)