1. Avoid IO-index racing
2. IO-index racing happened on resolustion switching
and mouse moving at the same time
3. System hung while IO-index racing occurred.
Signed-off-by: KuoHsiang Chou <[email protected]>
---
drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
1 file changed, 36 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index 79a361867..1d8fa70c5 100644
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
uint32_t base, uint8_t index,
uint8_t mask, uint8_t val)
{
- u8 tmp;
- ast_io_write8(ast, base, index);
- tmp = (ast_io_read8(ast, base + 1) & mask) | val;
- ast_set_index_reg(ast, base, index, tmp);
+ uint16_t volatile usData;
+ uint8_t volatile jData;
+
+ do {
+ ast_io_write8(ast, base, index);
+ usData = ast_io_read16(ast, base);
+ } while ((uint8_t)(usData) != index);
+
+ jData = (uint8_t)(usData >> 8);
+ jData &= mask;
+ jData |= val;
+ usData = ((uint16_t) jData << 8) | (uint16_t) index;
+ ast_io_write16(ast, base, usData);
}
uint8_t ast_get_index_reg(struct ast_private *ast,
uint32_t base, uint8_t index)
{
- uint8_t ret;
- ast_io_write8(ast, base, index);
- ret = ast_io_read8(ast, base + 1);
- return ret;
+ uint16_t volatile usData;
+ uint8_t volatile jData;
+
+ do {
+ ast_io_write8(ast, base, index);
+ usData = ast_io_read16(ast, base);
+ } while ((uint8_t)(usData) != index);
+
+ jData = (uint8_t)(usData >> 8);
+
+ return jData;
}
uint8_t ast_get_index_reg_mask(struct ast_private *ast,
uint32_t base, uint8_t index, uint8_t mask)
{
- uint8_t ret;
- ast_io_write8(ast, base, index);
- ret = ast_io_read8(ast, base + 1) & mask;
- return ret;
+ uint16_t volatile usData;
+ uint8_t volatile jData;
+
+ do {
+ ast_io_write8(ast, base, index);
+ usData = ast_io_read16(ast, base);
+ } while ((uint8_t)(usData) != index);
+
+ jData = (uint8_t)(usData >> 8);
+ jData &= mask;
+
+ return jData;
}
static void ast_detect_config_mode(struct drm_device *dev, u32 *scu_rev)
--
2.18.4
Hi
Am 17.09.21 um 09:22 schrieb KuoHsiang Chou:
> 1. Avoid IO-index racing
> 2. IO-index racing happened on resolustion switching
> and mouse moving at the same time
> 3. System hung while IO-index racing occurred.
I'd say that there's something else going one here. Mode setting and
cursor movement should be protected against each other by DRM locking.
Changing these low-level functions would not solve the issues. I'll try
to reproduce the problem ASAP.
Best regards
Thomas
>
> Signed-off-by: KuoHsiang Chou <[email protected]>
> ---
> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
> 1 file changed, 36 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
> index 79a361867..1d8fa70c5 100644
> --- a/drivers/gpu/drm/ast/ast_main.c
> +++ b/drivers/gpu/drm/ast/ast_main.c
> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index,
> uint8_t mask, uint8_t val)
> {
> - u8 tmp;
> - ast_io_write8(ast, base, index);
> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
> - ast_set_index_reg(ast, base, index, tmp);
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> + jData |= val;
> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
> + ast_io_write16(ast, base, usData);
> }
>
> uint8_t ast_get_index_reg(struct ast_private *ast,
> uint32_t base, uint8_t index)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1);
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> +
> + return jData;
> }
>
> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index, uint8_t mask)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1) & mask;
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> +
> + return jData;
> }
>
> static void ast_detect_config_mode(struct drm_device *dev, u32 *scu_rev)
> --
> 2.18.4
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer
-----Original Message-----
From: Thomas Zimmermann [mailto:[email protected]]
Sent: Monday, September 20, 2021 4:17 PM
To: Kuo-Hsiang Chou <[email protected]>; [email protected]; [email protected]
Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
Hi
Am 17.09.21 um 09:22 schrieb KuoHsiang Chou:
> 1. Avoid IO-index racing
> 2. IO-index racing happened on resolustion switching
> and mouse moving at the same time
> 3. System hung while IO-index racing occurred.
I'd say that there's something else going one here. Mode setting and cursor movement should be protected against each other by DRM locking.
Changing these low-level functions would not solve the issues. I'll try to reproduce the problem ASAP.
Hi Thomas,
Sorry to interrupt you again!
May I understand the review's situation? Thanks!
Best Regards,
Kuo-Hsiang Chou
Best regards
Thomas
>
> Signed-off-by: KuoHsiang Chou <[email protected]>
> ---
> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
> 1 file changed, 36 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_main.c
> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
> --- a/drivers/gpu/drm/ast/ast_main.c
> +++ b/drivers/gpu/drm/ast/ast_main.c
> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index,
> uint8_t mask, uint8_t val)
> {
> - u8 tmp;
> - ast_io_write8(ast, base, index);
> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
> - ast_set_index_reg(ast, base, index, tmp);
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> + jData |= val;
> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
> + ast_io_write16(ast, base, usData);
> }
>
> uint8_t ast_get_index_reg(struct ast_private *ast,
> uint32_t base, uint8_t index)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1);
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> +
> + return jData;
> }
>
> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index, uint8_t mask)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1) & mask;
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> +
> + return jData;
> }
>
> static void ast_detect_config_mode(struct drm_device *dev, u32
> *scu_rev)
> --
> 2.18.4
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer
-----Original Message-----
From: Kuo-Hsiang Chou
Sent: Thursday, September 30, 2021 3:19 PM
To: Thomas Zimmermann <[email protected]>; [email protected]; [email protected]
Subject: RE: [PATCH] drm/ast: Atomic CR/SR reg R/W
Hi
-----Original Message-----
From: Thomas Zimmermann [mailto:[email protected]]
Sent: Monday, September 20, 2021 4:17 PM
To: Kuo-Hsiang Chou <[email protected]>; [email protected]; [email protected]
Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
Hi
Am 17.09.21 um 09:22 schrieb KuoHsiang Chou:
> 1. Avoid IO-index racing
> 2. IO-index racing happened on resolustion switching
> and mouse moving at the same time
> 3. System hung while IO-index racing occurred.
I'd say that there's something else going one here. Mode setting and cursor movement should be protected against each other by DRM locking.
Changing these low-level functions would not solve the issues. I'll try to reproduce the problem ASAP.
Hi Thomas,
Sorry to interrupt you again!
May I understand the review's situation? Thanks!
Hi Tomas,
Good day!
May I understand the review status, or is there anything I can do to improve it? Thanks!
Best Regards,
Kuo-Hsiang Chou
Best Regards,
Kuo-Hsiang Chou
Best regards
Thomas
>
> Signed-off-by: KuoHsiang Chou <[email protected]>
> ---
> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
> 1 file changed, 36 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_main.c
> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
> --- a/drivers/gpu/drm/ast/ast_main.c
> +++ b/drivers/gpu/drm/ast/ast_main.c
> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index,
> uint8_t mask, uint8_t val)
> {
> - u8 tmp;
> - ast_io_write8(ast, base, index);
> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
> - ast_set_index_reg(ast, base, index, tmp);
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> + jData |= val;
> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
> + ast_io_write16(ast, base, usData);
> }
>
> uint8_t ast_get_index_reg(struct ast_private *ast,
> uint32_t base, uint8_t index)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1);
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> +
> + return jData;
> }
>
> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
> uint32_t base, uint8_t index, uint8_t mask)
> {
> - uint8_t ret;
> - ast_io_write8(ast, base, index);
> - ret = ast_io_read8(ast, base + 1) & mask;
> - return ret;
> + uint16_t volatile usData;
> + uint8_t volatile jData;
> +
> + do {
> + ast_io_write8(ast, base, index);
> + usData = ast_io_read16(ast, base);
> + } while ((uint8_t)(usData) != index);
> +
> + jData = (uint8_t)(usData >> 8);
> + jData &= mask;
> +
> + return jData;
> }
>
> static void ast_detect_config_mode(struct drm_device *dev, u32
> *scu_rev)
> --
> 2.18.4
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer
Hi
Am 03.12.21 um 02:23 schrieb Kuo-Hsiang Chou:
>
>
> -----Original Message-----
> From: Kuo-Hsiang Chou
> Sent: Thursday, September 30, 2021 3:19 PM
> To: Thomas Zimmermann <[email protected]>; [email protected]; [email protected]
> Subject: RE: [PATCH] drm/ast: Atomic CR/SR reg R/W
>
> Hi
>
> -----Original Message-----
> From: Thomas Zimmermann [mailto:[email protected]]
> Sent: Monday, September 20, 2021 4:17 PM
> To: Kuo-Hsiang Chou <[email protected]>; [email protected]; [email protected]
> Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
>
> Hi
>
> Am 17.09.21 um 09:22 schrieb KuoHsiang Chou:
>> 1. Avoid IO-index racing
>> 2. IO-index racing happened on resolustion switching
>> and mouse moving at the same time
>> 3. System hung while IO-index racing occurred.
>
> I'd say that there's something else going one here. Mode setting and cursor movement should be protected against each other by DRM locking.
> Changing these low-level functions would not solve the issues. I'll try to reproduce the problem ASAP.
>
> Hi Thomas,
>
> Sorry to interrupt you again!
> May I understand the review's situation? Thanks!
Look, you really have to work with us during the review process. Don't
just expect us to tell you what to do.
I'm not going to merge this patch. As I said, I don't think it fixes the
problem. Mouse movement and resolution switching should not interfere
with each other. The DRM framework should guarantee that.
I cannot reproduce the issue, but there's most likely something else
happening here. How can the system switch resolution and change the
mouse at the same time?
Best regards
Thomas
>
> Hi Tomas,
> Good day!
> May I understand the review status, or is there anything I can do to improve it? Thanks!
>
> Best Regards,
> Kuo-Hsiang Chou
>
> Best Regards,
> Kuo-Hsiang Chou
>
> Best regards
> Thomas
>
>>
>> Signed-off-by: KuoHsiang Chou <[email protected]>
>> ---
>> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
>> 1 file changed, 36 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/ast/ast_main.c
>> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
>> --- a/drivers/gpu/drm/ast/ast_main.c
>> +++ b/drivers/gpu/drm/ast/ast_main.c
>> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
>> uint32_t base, uint8_t index,
>> uint8_t mask, uint8_t val)
>> {
>> - u8 tmp;
>> - ast_io_write8(ast, base, index);
>> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
>> - ast_set_index_reg(ast, base, index, tmp);
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> + jData &= mask;
>> + jData |= val;
>> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
>> + ast_io_write16(ast, base, usData);
>> }
>>
>> uint8_t ast_get_index_reg(struct ast_private *ast,
>> uint32_t base, uint8_t index)
>> {
>> - uint8_t ret;
>> - ast_io_write8(ast, base, index);
>> - ret = ast_io_read8(ast, base + 1);
>> - return ret;
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> +
>> + return jData;
>> }
>>
>> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
>> uint32_t base, uint8_t index, uint8_t mask)
>> {
>> - uint8_t ret;
>> - ast_io_write8(ast, base, index);
>> - ret = ast_io_read8(ast, base + 1) & mask;
>> - return ret;
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> + jData &= mask;
>> +
>> + return jData;
>> }
>>
>> static void ast_detect_config_mode(struct drm_device *dev, u32
>> *scu_rev)
>> --
>> 2.18.4
>>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Felix Imendörffer
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
Hi
-----Original Message-----
From: Thomas Zimmermann [mailto:[email protected]]
Sent: Friday, December 03, 2021 4:47 PM
To: Kuo-Hsiang Chou <[email protected]>; [email protected]; [email protected]
Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
Hi
Am 03.12.21 um 02:23 schrieb Kuo-Hsiang Chou:
>
>
> -----Original Message-----
> From: Kuo-Hsiang Chou
> Sent: Thursday, September 30, 2021 3:19 PM
> To: Thomas Zimmermann <[email protected]>;
> [email protected]; [email protected]
> Subject: RE: [PATCH] drm/ast: Atomic CR/SR reg R/W
>
> Hi
>
> -----Original Message-----
> From: Thomas Zimmermann [mailto:[email protected]]
> Sent: Monday, September 20, 2021 4:17 PM
> To: Kuo-Hsiang Chou <[email protected]>;
> [email protected]; [email protected]
> Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
>
> Hi
>
> Am 17.09.21 um 09:22 schrieb KuoHsiang Chou:
>> 1. Avoid IO-index racing
>> 2. IO-index racing happened on resolustion switching
>> and mouse moving at the same time 3. System hung while IO-index
>> racing occurred.
>
> I'd say that there's something else going one here. Mode setting and cursor movement should be protected against each other by DRM locking.
> Changing these low-level functions would not solve the issues. I'll try to reproduce the problem ASAP.
>
> Hi Thomas,
>
> Sorry to interrupt you again!
> May I understand the review's situation? Thanks!
Hi Thomas,
Look, you really have to work with us during the review process. Don't just expect us to tell you what to do.
Thanks! Got it.
I'm not going to merge this patch. As I said, I don't think it fixes the problem. Mouse movement and resolution switching should not interfere with each other. The DRM framework should guarantee that.
OK, thanks for your confirmation.
I cannot reproduce the issue, but there's most likely something else happening here. How can the system switch resolution and change the mouse at the same time?
Sure, we will check if there is a 100 percent method to reproduce the issue.
Thanks for your responses.
Regards,
Kuo-Hsiang Chou
Best regards
Thomas
>
> Hi Tomas,
> Good day!
> May I understand the review status, or is there anything I can do to improve it? Thanks!
>
> Best Regards,
> Kuo-Hsiang Chou
>
> Best Regards,
> Kuo-Hsiang Chou
>
> Best regards
> Thomas
>
>>
>> Signed-off-by: KuoHsiang Chou <[email protected]>
>> ---
>> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
>> 1 file changed, 36 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/ast/ast_main.c
>> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
>> --- a/drivers/gpu/drm/ast/ast_main.c
>> +++ b/drivers/gpu/drm/ast/ast_main.c
>> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
>> uint32_t base, uint8_t index,
>> uint8_t mask, uint8_t val)
>> {
>> - u8 tmp;
>> - ast_io_write8(ast, base, index);
>> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
>> - ast_set_index_reg(ast, base, index, tmp);
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> + jData &= mask;
>> + jData |= val;
>> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
>> + ast_io_write16(ast, base, usData);
>> }
>>
>> uint8_t ast_get_index_reg(struct ast_private *ast,
>> uint32_t base, uint8_t index)
>> {
>> - uint8_t ret;
>> - ast_io_write8(ast, base, index);
>> - ret = ast_io_read8(ast, base + 1);
>> - return ret;
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> +
>> + return jData;
>> }
>>
>> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
>> uint32_t base, uint8_t index, uint8_t mask)
>> {
>> - uint8_t ret;
>> - ast_io_write8(ast, base, index);
>> - ret = ast_io_read8(ast, base + 1) & mask;
>> - return ret;
>> + uint16_t volatile usData;
>> + uint8_t volatile jData;
>> +
>> + do {
>> + ast_io_write8(ast, base, index);
>> + usData = ast_io_read16(ast, base);
>> + } while ((uint8_t)(usData) != index);
>> +
>> + jData = (uint8_t)(usData >> 8);
>> + jData &= mask;
>> +
>> + return jData;
>> }
>>
>> static void ast_detect_config_mode(struct drm_device *dev, u32
>> *scu_rev)
>> --
>> 2.18.4
>>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg)
> Geschäftsführer: Felix Imendörffer
>
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
Hi Thomas,
Thanks for your kindly assistance.
Regards
Kuo-Hsiang Chou
-----Original Message-----
From: Thomas Zimmermann [mailto:[email protected]]
Sent: Monday, May 02, 2022 10:33 PM
To: Kuo-Hsiang Chou <[email protected]>; [email protected]; [email protected]
Cc: Ryan Chen <[email protected]>; [email protected]; 清水修(o-shimizu)-台灣NEC <[email protected]>; Jenmin Yuan <[email protected]>; [email protected]; Arc Sung <[email protected]>; Luke Chen <[email protected]>
Subject: Re: [PATCH] drm/ast: Atomic CR/SR reg R/W
Hi
Am 06.12.21 um 02:38 schrieb Kuo-Hsiang Chou:
> I'm not going to merge this patch. As I said, I don't think it fixes the problem. Mouse movement and resolution switching should not interfere with each other. The DRM framework should guarantee that.
> OK, thanks for your confirmation.
>
> I cannot reproduce the issue, but there's most likely something else happening here. How can the system switch resolution and change the mouse at the same time?
> Sure, we will check if there is a 100 percent method to reproduce the issue.
> Thanks for your responses.
I've been away for a while; sorry for all this taking so long. I've meanwhile been able to reproduce the problem. It happens when GNOME concurrently tries to set the video mode and read the available video modes from EDID. Reading EDID is not protected against concurrent mode setting or cursor movement.
I've posted a patchset that should fix the problem. See [1].
Best regards
Thomas
[1]
https://lore.kernel.org/dri-devel/[email protected]/T/#t
>
> Regards,
> Kuo-Hsiang Chou
>
> Best regards
> Thomas
>
>>
>> Hi Tomas,
>> Good day!
>> May I understand the review status, or is there anything I can do to improve it? Thanks!
>>
>> Best Regards,
>> Kuo-Hsiang Chou
>>
>> Best Regards,
>> Kuo-Hsiang Chou
>>
>> Best regards
>> Thomas
>>
>>>
>>> Signed-off-by: KuoHsiang Chou <[email protected]>
>>> ---
>>> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
>>> 1 file changed, 36 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/ast/ast_main.c
>>> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
>>> --- a/drivers/gpu/drm/ast/ast_main.c
>>> +++ b/drivers/gpu/drm/ast/ast_main.c
>>> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
>>> uint32_t base, uint8_t index,
>>> uint8_t mask, uint8_t val)
>>> {
>>> - u8 tmp;
>>> - ast_io_write8(ast, base, index);
>>> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
>>> - ast_set_index_reg(ast, base, index, tmp);
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> + jData &= mask;
>>> + jData |= val;
>>> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
>>> + ast_io_write16(ast, base, usData);
>>> }
>>>
>>> uint8_t ast_get_index_reg(struct ast_private *ast,
>>> uint32_t base, uint8_t index)
>>> {
>>> - uint8_t ret;
>>> - ast_io_write8(ast, base, index);
>>> - ret = ast_io_read8(ast, base + 1);
>>> - return ret;
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> +
>>> + return jData;
>>> }
>>>
>>> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
>>> uint32_t base, uint8_t index, uint8_t mask)
>>> {
>>> - uint8_t ret;
>>> - ast_io_write8(ast, base, index);
>>> - ret = ast_io_read8(ast, base + 1) & mask;
>>> - return ret;
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> + jData &= mask;
>>> +
>>> + return jData;
>>> }
>>>
>>> static void ast_detect_config_mode(struct drm_device *dev, u32
>>> *scu_rev)
>>> --
>>> 2.18.4
>>>
>>
>> --
>> Thomas Zimmermann
>> Graphics Driver Developer
>> SUSE Software Solutions Germany GmbH
>> Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg)
>> Geschäftsführer: Felix Imendörffer
>>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg)
> Geschäftsführer: Ivo Totev
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
Hi
Am 06.12.21 um 02:38 schrieb Kuo-Hsiang Chou:
> I'm not going to merge this patch. As I said, I don't think it fixes the problem. Mouse movement and resolution switching should not interfere with each other. The DRM framework should guarantee that.
> OK, thanks for your confirmation.
>
> I cannot reproduce the issue, but there's most likely something else happening here. How can the system switch resolution and change the mouse at the same time?
> Sure, we will check if there is a 100 percent method to reproduce the issue.
> Thanks for your responses.
I've been away for a while; sorry for all this taking so long. I've
meanwhile been able to reproduce the problem. It happens when GNOME
concurrently tries to set the video mode and read the available video
modes from EDID. Reading EDID is not protected against concurrent mode
setting or cursor movement.
I've posted a patchset that should fix the problem. See [1].
Best regards
Thomas
[1]
https://lore.kernel.org/dri-devel/[email protected]/T/#t
>
> Regards,
> Kuo-Hsiang Chou
>
> Best regards
> Thomas
>
>>
>> Hi Tomas,
>> Good day!
>> May I understand the review status, or is there anything I can do to improve it? Thanks!
>>
>> Best Regards,
>> Kuo-Hsiang Chou
>>
>> Best Regards,
>> Kuo-Hsiang Chou
>>
>> Best regards
>> Thomas
>>
>>>
>>> Signed-off-by: KuoHsiang Chou <[email protected]>
>>> ---
>>> drivers/gpu/drm/ast/ast_main.c | 48 +++++++++++++++++++++++++---------
>>> 1 file changed, 36 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/ast/ast_main.c
>>> b/drivers/gpu/drm/ast/ast_main.c index 79a361867..1d8fa70c5 100644
>>> --- a/drivers/gpu/drm/ast/ast_main.c
>>> +++ b/drivers/gpu/drm/ast/ast_main.c
>>> @@ -41,28 +41,52 @@ void ast_set_index_reg_mask(struct ast_private *ast,
>>> uint32_t base, uint8_t index,
>>> uint8_t mask, uint8_t val)
>>> {
>>> - u8 tmp;
>>> - ast_io_write8(ast, base, index);
>>> - tmp = (ast_io_read8(ast, base + 1) & mask) | val;
>>> - ast_set_index_reg(ast, base, index, tmp);
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> + jData &= mask;
>>> + jData |= val;
>>> + usData = ((uint16_t) jData << 8) | (uint16_t) index;
>>> + ast_io_write16(ast, base, usData);
>>> }
>>>
>>> uint8_t ast_get_index_reg(struct ast_private *ast,
>>> uint32_t base, uint8_t index)
>>> {
>>> - uint8_t ret;
>>> - ast_io_write8(ast, base, index);
>>> - ret = ast_io_read8(ast, base + 1);
>>> - return ret;
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> +
>>> + return jData;
>>> }
>>>
>>> uint8_t ast_get_index_reg_mask(struct ast_private *ast,
>>> uint32_t base, uint8_t index, uint8_t mask)
>>> {
>>> - uint8_t ret;
>>> - ast_io_write8(ast, base, index);
>>> - ret = ast_io_read8(ast, base + 1) & mask;
>>> - return ret;
>>> + uint16_t volatile usData;
>>> + uint8_t volatile jData;
>>> +
>>> + do {
>>> + ast_io_write8(ast, base, index);
>>> + usData = ast_io_read16(ast, base);
>>> + } while ((uint8_t)(usData) != index);
>>> +
>>> + jData = (uint8_t)(usData >> 8);
>>> + jData &= mask;
>>> +
>>> + return jData;
>>> }
>>>
>>> static void ast_detect_config_mode(struct drm_device *dev, u32
>>> *scu_rev)
>>> --
>>> 2.18.4
>>>
>>
>> --
>> Thomas Zimmermann
>> Graphics Driver Developer
>> SUSE Software Solutions Germany GmbH
>> Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg)
>> Geschäftsführer: Felix Imendörffer
>>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Ivo Totev
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev