diff mbox series

[v1,2/2] clk: qcom: dispcc: Remove support of disp_cc_mdss_rscc_ahb_clk

Message ID 1581423236-21341-2-git-send-email-tdas@codeaurora.org (mailing list archive)
State New, archived
Headers show
Series [v1,1/2] clk: qcom: videocc: Update the clock flag for video_cc_vcodec0_core_clk | expand

Commit Message

Taniya Das Feb. 11, 2020, 12:13 p.m. UTC 
The disp_cc_mdss_rscc_ahb_clk is default enabled from hardware and thus
does not require to be marked CRITICAL. This which would allow the RCG to
be turned OFF when the display turns OFF and not blocking XO.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
---
 drivers/clk/qcom/dispcc-sc7180.c | 19 -------------------
 1 file changed, 19 deletions(-)

--
Qualcomm INDIA, on behalf of Qualcomm Innovation Center, Inc.is a member
of the Code Aurora Forum, hosted by the  Linux Foundation.

Comments

Stephen Boyd Feb. 12, 2020, 11:03 p.m. UTC | #1 
Quoting Taniya Das (2020-02-11 04:13:56)
> The disp_cc_mdss_rscc_ahb_clk is default enabled from hardware and thus
> does not require to be marked CRITICAL. This which would allow the RCG to
> be turned OFF when the display turns OFF and not blocking XO.
> 
> Signed-off-by: Taniya Das <tdas@codeaurora.org>
> ---

Applied to clk-fixes
Matthias Kaehlcke March 3, 2020, 8:16 p.m. UTC | #2 
On Tue, Feb 11, 2020 at 05:43:56PM +0530, Taniya Das wrote:
> The disp_cc_mdss_rscc_ahb_clk is default enabled from hardware and thus
> does not require to be marked CRITICAL. This which would allow the RCG to
> be turned OFF when the display turns OFF and not blocking XO.
> 
> Signed-off-by: Taniya Das <tdas@codeaurora.org>
> ---
>  drivers/clk/qcom/dispcc-sc7180.c | 19 -------------------
>  1 file changed, 19 deletions(-)
> 
> diff --git a/drivers/clk/qcom/dispcc-sc7180.c b/drivers/clk/qcom/dispcc-sc7180.c
> index dd7af41..0a5d395 100644
> --- a/drivers/clk/qcom/dispcc-sc7180.c
> +++ b/drivers/clk/qcom/dispcc-sc7180.c
> @@ -592,24 +592,6 @@ static struct clk_branch disp_cc_mdss_rot_clk = {
>  	},
>  };
> 
> -static struct clk_branch disp_cc_mdss_rscc_ahb_clk = {
> -	.halt_reg = 0x400c,
> -	.halt_check = BRANCH_HALT,
> -	.clkr = {
> -		.enable_reg = 0x400c,
> -		.enable_mask = BIT(0),
> -		.hw.init = &(struct clk_init_data){
> -			.name = "disp_cc_mdss_rscc_ahb_clk",
> -			.parent_data = &(const struct clk_parent_data){
> -				.hw = &disp_cc_mdss_ahb_clk_src.clkr.hw,
> -			},
> -			.num_parents = 1,
> -			.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT,
> -			.ops = &clk_branch2_ops,
> -		},
> -	},
> -};
> -
>  static struct clk_branch disp_cc_mdss_rscc_vsync_clk = {
>  	.halt_reg = 0x4008,
>  	.halt_check = BRANCH_HALT,
> @@ -687,7 +669,6 @@ static struct clk_regmap *disp_cc_sc7180_clocks[] = {
>  	[DISP_CC_MDSS_PCLK0_CLK_SRC] = &disp_cc_mdss_pclk0_clk_src.clkr,
>  	[DISP_CC_MDSS_ROT_CLK] = &disp_cc_mdss_rot_clk.clkr,
>  	[DISP_CC_MDSS_ROT_CLK_SRC] = &disp_cc_mdss_rot_clk_src.clkr,
> -	[DISP_CC_MDSS_RSCC_AHB_CLK] = &disp_cc_mdss_rscc_ahb_clk.clkr,
>  	[DISP_CC_MDSS_RSCC_VSYNC_CLK] = &disp_cc_mdss_rscc_vsync_clk.clkr,
>  	[DISP_CC_MDSS_VSYNC_CLK] = &disp_cc_mdss_vsync_clk.clkr,
>  	[DISP_CC_MDSS_VSYNC_CLK_SRC] = &disp_cc_mdss_vsync_clk_src.clkr,

We found that this change leads to a panic at boot time on SC7180 devices
without display configuration (e.g. the SC7180 IDP with the current DT):

[    2.412820] SError Interrupt on CPU6, code 0xbe000411 -- SError
[    2.412822] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
[    2.412822] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
[    2.412823] pstate: 20c00089 (nzCv daIf +PAN +UAO)
[    2.412823] pc : regmap_mmio_read32le+0x28/0x40
[    2.412823] lr : regmap_mmio_read+0x44/0x6c
[    2.412824] sp : ffffffc01005ba90
[    2.412824] x29: ffffffc01005ba90 x28: 0000000000000000
[    2.412825] x27: 0000000000000000 x26: 0000000000000000
[    2.412826] x25: 0000000000000000 x24: ffffffd1f4aed018
[    2.412827] x23: ffffffd1f4c12148 x22: ffffff8177a6c800
[    2.412827] x21: 0000000000002048 x20: ffffff8177489e00
[    2.412828] x19: 0000000000002048 x18: 000000004a746f4b
[    2.412829] x17: 00000000d0e09034 x16: 000000005079b450
[    2.412830] x15: 000000003e3bf7ed x14: 0000000000007fff
[    2.412830] x13: ffffff8177309b40 x12: 0000000000000000
[    2.412831] x11: 0000000000000000 x10: 0000000000000000
[    2.412831] x9 : 0000000000000001 x8 : ffffffc011c02048
[    2.412832] x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000
[    2.412833] x5 : 0000000000000000 x4 : 0000000000000000
[    2.412834] x3 : 0000000000000000 x2 : ffffffc01005bb84
[    2.412834] x1 : 0000000000002048 x0 : 0000000080000000
[    2.412835] Kernel panic - not syncing: Asynchronous SError Interrupt
[    2.412836] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
[    2.412836] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
[    2.412836] Call trace:
[    2.412837]  dump_backtrace+0x0/0x150
[    2.412837]  show_stack+0x20/0x2c
[    2.412837]  dump_stack+0xa0/0xd8
[    2.412838]  panic+0x158/0x360
[    2.412838]  panic+0x0/0x360
[    2.412838]  arm64_serror_panic+0x78/0x84
[    2.412839]  do_serror+0x110/0x118
[    2.412839]  el1_error+0x84/0xf8
[    2.412839]  regmap_mmio_read32le+0x28/0x40
[    2.412840]  regmap_mmio_read+0x44/0x6c
[    2.412840]  _regmap_bus_reg_read+0x34/0x44
[    2.412841]  _regmap_read+0x88/0x164
[    2.412841]  regmap_read+0x54/0x78
[    2.412841]  clk_is_enabled_regmap+0x3c/0x8c
[    2.412842]  clk_core_is_enabled+0x68/0xac
[    2.412842]  clk_disable_unused_subtree+0x90/0x22c
[    2.412843]  clk_disable_unused_subtree+0x34/0x22c
[    2.412843]  clk_disable_unused+0x74/0x108
[    2.412843]  do_one_initcall+0x13c/0x2c8
[    2.412844]  do_initcall_level+0x144/0x16c
[    2.412844]  do_basic_setup+0x30/0x48
[    2.412844]  kernel_init_freeable+0xc4/0x140
[    2.412845]  kernel_init+0x14/0x100
[    2.412845]  ret_from_fork+0x10/0x18
[    2.412858] SMP: stopping secondary CPUs
[    2.412859] Kernel Offset: 0x11e3a00000 from 0xffffffc010000000
[    2.412859] PHYS_OFFSET: 0xffffffe780000000
[    2.412860] CPU features: 0x0006,2a80aa18
[    2.412860] Memory Limit: none
Taniya Das March 4, 2020, 3:35 a.m. UTC | #3 
On 3/4/2020 1:46 AM, Matthias Kaehlcke wrote:
> On Tue, Feb 11, 2020 at 05:43:56PM +0530, Taniya Das wrote:
>> The disp_cc_mdss_rscc_ahb_clk is default enabled from hardware and thus
>> does not require to be marked CRITICAL. This which would allow the RCG to
>> be turned OFF when the display turns OFF and not blocking XO.
>>
>> Signed-off-by: Taniya Das <tdas@codeaurora.org>
>> ---
>>   drivers/clk/qcom/dispcc-sc7180.c | 19 -------------------
>>   1 file changed, 19 deletions(-)
>>
>> diff --git a/drivers/clk/qcom/dispcc-sc7180.c b/drivers/clk/qcom/dispcc-sc7180.c
>> index dd7af41..0a5d395 100644
>> --- a/drivers/clk/qcom/dispcc-sc7180.c
>> +++ b/drivers/clk/qcom/dispcc-sc7180.c
>> @@ -592,24 +592,6 @@ static struct clk_branch disp_cc_mdss_rot_clk = {
>>   	},
>>   };
>>
>> -static struct clk_branch disp_cc_mdss_rscc_ahb_clk = {
>> -	.halt_reg = 0x400c,
>> -	.halt_check = BRANCH_HALT,
>> -	.clkr = {
>> -		.enable_reg = 0x400c,
>> -		.enable_mask = BIT(0),
>> -		.hw.init = &(struct clk_init_data){
>> -			.name = "disp_cc_mdss_rscc_ahb_clk",
>> -			.parent_data = &(const struct clk_parent_data){
>> -				.hw = &disp_cc_mdss_ahb_clk_src.clkr.hw,
>> -			},
>> -			.num_parents = 1,
>> -			.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT,
>> -			.ops = &clk_branch2_ops,
>> -		},
>> -	},
>> -};
>> -
>>   static struct clk_branch disp_cc_mdss_rscc_vsync_clk = {
>>   	.halt_reg = 0x4008,
>>   	.halt_check = BRANCH_HALT,
>> @@ -687,7 +669,6 @@ static struct clk_regmap *disp_cc_sc7180_clocks[] = {
>>   	[DISP_CC_MDSS_PCLK0_CLK_SRC] = &disp_cc_mdss_pclk0_clk_src.clkr,
>>   	[DISP_CC_MDSS_ROT_CLK] = &disp_cc_mdss_rot_clk.clkr,
>>   	[DISP_CC_MDSS_ROT_CLK_SRC] = &disp_cc_mdss_rot_clk_src.clkr,
>> -	[DISP_CC_MDSS_RSCC_AHB_CLK] = &disp_cc_mdss_rscc_ahb_clk.clkr,
>>   	[DISP_CC_MDSS_RSCC_VSYNC_CLK] = &disp_cc_mdss_rscc_vsync_clk.clkr,
>>   	[DISP_CC_MDSS_VSYNC_CLK] = &disp_cc_mdss_vsync_clk.clkr,
>>   	[DISP_CC_MDSS_VSYNC_CLK_SRC] = &disp_cc_mdss_vsync_clk_src.clkr,
> 
> We found that this change leads to a panic at boot time on SC7180 devices
> without display configuration (e.g. the SC7180 IDP with the current DT):
> 
> [    2.412820] SError Interrupt on CPU6, code 0xbe000411 -- SError
> [    2.412822] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
> [    2.412822] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
> [    2.412823] pstate: 20c00089 (nzCv daIf +PAN +UAO)
> [    2.412823] pc : regmap_mmio_read32le+0x28/0x40
> [    2.412823] lr : regmap_mmio_read+0x44/0x6c
> [    2.412824] sp : ffffffc01005ba90
> [    2.412824] x29: ffffffc01005ba90 x28: 0000000000000000
> [    2.412825] x27: 0000000000000000 x26: 0000000000000000
> [    2.412826] x25: 0000000000000000 x24: ffffffd1f4aed018
> [    2.412827] x23: ffffffd1f4c12148 x22: ffffff8177a6c800
> [    2.412827] x21: 0000000000002048 x20: ffffff8177489e00
> [    2.412828] x19: 0000000000002048 x18: 000000004a746f4b
> [    2.412829] x17: 00000000d0e09034 x16: 000000005079b450
> [    2.412830] x15: 000000003e3bf7ed x14: 0000000000007fff
> [    2.412830] x13: ffffff8177309b40 x12: 0000000000000000
> [    2.412831] x11: 0000000000000000 x10: 0000000000000000
> [    2.412831] x9 : 0000000000000001 x8 : ffffffc011c02048
> [    2.412832] x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000
> [    2.412833] x5 : 0000000000000000 x4 : 0000000000000000
> [    2.412834] x3 : 0000000000000000 x2 : ffffffc01005bb84
> [    2.412834] x1 : 0000000000002048 x0 : 0000000080000000
> [    2.412835] Kernel panic - not syncing: Asynchronous SError Interrupt
> [    2.412836] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
> [    2.412836] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
> [    2.412836] Call trace:
> [    2.412837]  dump_backtrace+0x0/0x150
> [    2.412837]  show_stack+0x20/0x2c
> [    2.412837]  dump_stack+0xa0/0xd8
> [    2.412838]  panic+0x158/0x360
> [    2.412838]  panic+0x0/0x360
> [    2.412838]  arm64_serror_panic+0x78/0x84
> [    2.412839]  do_serror+0x110/0x118
> [    2.412839]  el1_error+0x84/0xf8
> [    2.412839]  regmap_mmio_read32le+0x28/0x40
> [    2.412840]  regmap_mmio_read+0x44/0x6c
> [    2.412840]  _regmap_bus_reg_read+0x34/0x44
> [    2.412841]  _regmap_read+0x88/0x164
> [    2.412841]  regmap_read+0x54/0x78
> [    2.412841]  clk_is_enabled_regmap+0x3c/0x8c
> [    2.412842]  clk_core_is_enabled+0x68/0xac
> [    2.412842]  clk_disable_unused_subtree+0x90/0x22c
> [    2.412843]  clk_disable_unused_subtree+0x34/0x22c
> [    2.412843]  clk_disable_unused+0x74/0x108
> [    2.412843]  do_one_initcall+0x13c/0x2c8
> [    2.412844]  do_initcall_level+0x144/0x16c
> [    2.412844]  do_basic_setup+0x30/0x48
> [    2.412844]  kernel_init_freeable+0xc4/0x140
> [    2.412845]  kernel_init+0x14/0x100
> [    2.412845]  ret_from_fork+0x10/0x18
> [    2.412858] SMP: stopping secondary CPUs
> [    2.412859] Kernel Offset: 0x11e3a00000 from 0xffffffc010000000
> [    2.412859] PHYS_OFFSET: 0xffffffe780000000
> [    2.412860] CPU features: 0x0006,2a80aa18
> [    2.412860] Memory Limit: none
> 

Hi Matthias,

The display device node is not present and we encounter this crash, 
would it be possible to add ALWAYS_ON for the MDSS GDSC and give it a try.
Matthias Kaehlcke March 4, 2020, 5:09 p.m. UTC | #4 
Hi Taniya,

On Wed, Mar 04, 2020 at 09:05:20AM +0530, Taniya Das wrote:
> 
> On 3/4/2020 1:46 AM, Matthias Kaehlcke wrote:
> > On Tue, Feb 11, 2020 at 05:43:56PM +0530, Taniya Das wrote:
> > > The disp_cc_mdss_rscc_ahb_clk is default enabled from hardware and thus
> > > does not require to be marked CRITICAL. This which would allow the RCG to
> > > be turned OFF when the display turns OFF and not blocking XO.
> > > 
> > > Signed-off-by: Taniya Das <tdas@codeaurora.org>
> > > ---
> > >   drivers/clk/qcom/dispcc-sc7180.c | 19 -------------------
> > >   1 file changed, 19 deletions(-)
> > > 
> > > diff --git a/drivers/clk/qcom/dispcc-sc7180.c b/drivers/clk/qcom/dispcc-sc7180.c
> > > index dd7af41..0a5d395 100644
> > > --- a/drivers/clk/qcom/dispcc-sc7180.c
> > > +++ b/drivers/clk/qcom/dispcc-sc7180.c
> > > @@ -592,24 +592,6 @@ static struct clk_branch disp_cc_mdss_rot_clk = {
> > >   	},
> > >   };
> > > 
> > > -static struct clk_branch disp_cc_mdss_rscc_ahb_clk = {
> > > -	.halt_reg = 0x400c,
> > > -	.halt_check = BRANCH_HALT,
> > > -	.clkr = {
> > > -		.enable_reg = 0x400c,
> > > -		.enable_mask = BIT(0),
> > > -		.hw.init = &(struct clk_init_data){
> > > -			.name = "disp_cc_mdss_rscc_ahb_clk",
> > > -			.parent_data = &(const struct clk_parent_data){
> > > -				.hw = &disp_cc_mdss_ahb_clk_src.clkr.hw,
> > > -			},
> > > -			.num_parents = 1,
> > > -			.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT,
> > > -			.ops = &clk_branch2_ops,
> > > -		},
> > > -	},
> > > -};
> > > -
> > >   static struct clk_branch disp_cc_mdss_rscc_vsync_clk = {
> > >   	.halt_reg = 0x4008,
> > >   	.halt_check = BRANCH_HALT,
> > > @@ -687,7 +669,6 @@ static struct clk_regmap *disp_cc_sc7180_clocks[] = {
> > >   	[DISP_CC_MDSS_PCLK0_CLK_SRC] = &disp_cc_mdss_pclk0_clk_src.clkr,
> > >   	[DISP_CC_MDSS_ROT_CLK] = &disp_cc_mdss_rot_clk.clkr,
> > >   	[DISP_CC_MDSS_ROT_CLK_SRC] = &disp_cc_mdss_rot_clk_src.clkr,
> > > -	[DISP_CC_MDSS_RSCC_AHB_CLK] = &disp_cc_mdss_rscc_ahb_clk.clkr,
> > >   	[DISP_CC_MDSS_RSCC_VSYNC_CLK] = &disp_cc_mdss_rscc_vsync_clk.clkr,
> > >   	[DISP_CC_MDSS_VSYNC_CLK] = &disp_cc_mdss_vsync_clk.clkr,
> > >   	[DISP_CC_MDSS_VSYNC_CLK_SRC] = &disp_cc_mdss_vsync_clk_src.clkr,
> > 
> > We found that this change leads to a panic at boot time on SC7180 devices
> > without display configuration (e.g. the SC7180 IDP with the current DT):
> > 
> > [    2.412820] SError Interrupt on CPU6, code 0xbe000411 -- SError
> > [    2.412822] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
> > [    2.412822] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
> > [    2.412823] pstate: 20c00089 (nzCv daIf +PAN +UAO)
> > [    2.412823] pc : regmap_mmio_read32le+0x28/0x40
> > [    2.412823] lr : regmap_mmio_read+0x44/0x6c
> > [    2.412824] sp : ffffffc01005ba90
> > [    2.412824] x29: ffffffc01005ba90 x28: 0000000000000000
> > [    2.412825] x27: 0000000000000000 x26: 0000000000000000
> > [    2.412826] x25: 0000000000000000 x24: ffffffd1f4aed018
> > [    2.412827] x23: ffffffd1f4c12148 x22: ffffff8177a6c800
> > [    2.412827] x21: 0000000000002048 x20: ffffff8177489e00
> > [    2.412828] x19: 0000000000002048 x18: 000000004a746f4b
> > [    2.412829] x17: 00000000d0e09034 x16: 000000005079b450
> > [    2.412830] x15: 000000003e3bf7ed x14: 0000000000007fff
> > [    2.412830] x13: ffffff8177309b40 x12: 0000000000000000
> > [    2.412831] x11: 0000000000000000 x10: 0000000000000000
> > [    2.412831] x9 : 0000000000000001 x8 : ffffffc011c02048
> > [    2.412832] x7 : aaaaaaaaaaaaaaaa x6 : 0000000000000000
> > [    2.412833] x5 : 0000000000000000 x4 : 0000000000000000
> > [    2.412834] x3 : 0000000000000000 x2 : ffffffc01005bb84
> > [    2.412834] x1 : 0000000000002048 x0 : 0000000080000000
> > [    2.412835] Kernel panic - not syncing: Asynchronous SError Interrupt
> > [    2.412836] CPU: 6 PID: 1 Comm: swapper/0 Tainted: G S                5.4.22 #103
> > [    2.412836] Hardware name: Qualcomm Technologies, Inc. SC7180 IDP (DT)
> > [    2.412836] Call trace:
> > [    2.412837]  dump_backtrace+0x0/0x150
> > [    2.412837]  show_stack+0x20/0x2c
> > [    2.412837]  dump_stack+0xa0/0xd8
> > [    2.412838]  panic+0x158/0x360
> > [    2.412838]  panic+0x0/0x360
> > [    2.412838]  arm64_serror_panic+0x78/0x84
> > [    2.412839]  do_serror+0x110/0x118
> > [    2.412839]  el1_error+0x84/0xf8
> > [    2.412839]  regmap_mmio_read32le+0x28/0x40
> > [    2.412840]  regmap_mmio_read+0x44/0x6c
> > [    2.412840]  _regmap_bus_reg_read+0x34/0x44
> > [    2.412841]  _regmap_read+0x88/0x164
> > [    2.412841]  regmap_read+0x54/0x78
> > [    2.412841]  clk_is_enabled_regmap+0x3c/0x8c
> > [    2.412842]  clk_core_is_enabled+0x68/0xac
> > [    2.412842]  clk_disable_unused_subtree+0x90/0x22c
> > [    2.412843]  clk_disable_unused_subtree+0x34/0x22c
> > [    2.412843]  clk_disable_unused+0x74/0x108
> > [    2.412843]  do_one_initcall+0x13c/0x2c8
> > [    2.412844]  do_initcall_level+0x144/0x16c
> > [    2.412844]  do_basic_setup+0x30/0x48
> > [    2.412844]  kernel_init_freeable+0xc4/0x140
> > [    2.412845]  kernel_init+0x14/0x100
> > [    2.412845]  ret_from_fork+0x10/0x18
> > [    2.412858] SMP: stopping secondary CPUs
> > [    2.412859] Kernel Offset: 0x11e3a00000 from 0xffffffc010000000
> > [    2.412859] PHYS_OFFSET: 0xffffffe780000000
> > [    2.412860] CPU features: 0x0006,2a80aa18
> > [    2.412860] Memory Limit: none
> > 
> 
> Hi Matthias,
> 
> The display device node is not present and we encounter this crash, would it
> be possible to add ALWAYS_ON for the MDSS GDSC and give it a try.

It still crashes when ALWAYS_ON is set for the MDSS GDSC.
Stephen Boyd March 13, 2020, 6:01 p.m. UTC | #5 
Quoting Matthias Kaehlcke (2020-03-04 09:09:39)
> Hi Taniya,
> 
> On Wed, Mar 04, 2020 at 09:05:20AM +0530, Taniya Das wrote:
> > 
> > Hi Matthias,
> > 
> > The display device node is not present and we encounter this crash, would it
> > be possible to add ALWAYS_ON for the MDSS GDSC and give it a try.
> 
> It still crashes when ALWAYS_ON is set for the MDSS GDSC.

Any updates here? I'm about to send this patch off to Linus and I'm
wondering if there will be a resolution besides reverting it.
Stephen Boyd March 16, 2020, 6:33 p.m. UTC | #6 
Quoting Taniya Das (2020-03-14 04:08:47)
> I would require you suggestion on the below.
> 
> On 3/13/2020 11:31 PM, Stephen Boyd wrote:
> > Quoting Matthias Kaehlcke (2020-03-04 09:09:39)
> >> Hi Taniya,
> >>
> >> On Wed, Mar 04, 2020 at 09:05:20AM +0530, Taniya Das wrote:
> >>>
> >>> Hi Matthias,
> >>>
> >>> The display device node is not present and we encounter this crash, would it
> >>> be possible to add ALWAYS_ON for the MDSS GDSC and give it a try.
> >>
> >> It still crashes when ALWAYS_ON is set for the MDSS GDSC.
> > 
> > Any updates here? I'm about to send this patch off to Linus and I'm
> > wondering if there will be a resolution besides reverting it.
> > 
> 
> Looks like the AHB clock needs to be left enabled till the last clocks 
> get disabled. I need to add a new dependency o n this clock.
> 
> Hi Stephen,
> 
> 
> Any way to keep this dependency using the framework  or I need to split 
> the probes to register them independently?
> 

Sorry, I don't understand the problem fully. This AHB clk is left on in
the bootloader? Why do we need to touch it if it's always left enabled?
Is it actually the case that the bootloader hasn't turned this clk on
and we're getting lucky having it marked here as CLK_IS_CRITICAL? Can we
force it on in driver probe and then ignore it after that?
diff mbox series

Patch

diff --git a/drivers/clk/qcom/dispcc-sc7180.c b/drivers/clk/qcom/dispcc-sc7180.c
index dd7af41..0a5d395 100644
--- a/drivers/clk/qcom/dispcc-sc7180.c
+++ b/drivers/clk/qcom/dispcc-sc7180.c
@@ -592,24 +592,6 @@  static struct clk_branch disp_cc_mdss_rot_clk = {
 	},
 };

-static struct clk_branch disp_cc_mdss_rscc_ahb_clk = {
-	.halt_reg = 0x400c,
-	.halt_check = BRANCH_HALT,
-	.clkr = {
-		.enable_reg = 0x400c,
-		.enable_mask = BIT(0),
-		.hw.init = &(struct clk_init_data){
-			.name = "disp_cc_mdss_rscc_ahb_clk",
-			.parent_data = &(const struct clk_parent_data){
-				.hw = &disp_cc_mdss_ahb_clk_src.clkr.hw,
-			},
-			.num_parents = 1,
-			.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT,
-			.ops = &clk_branch2_ops,
-		},
-	},
-};
-
 static struct clk_branch disp_cc_mdss_rscc_vsync_clk = {
 	.halt_reg = 0x4008,
 	.halt_check = BRANCH_HALT,
@@ -687,7 +669,6 @@  static struct clk_regmap *disp_cc_sc7180_clocks[] = {
 	[DISP_CC_MDSS_PCLK0_CLK_SRC] = &disp_cc_mdss_pclk0_clk_src.clkr,
 	[DISP_CC_MDSS_ROT_CLK] = &disp_cc_mdss_rot_clk.clkr,
 	[DISP_CC_MDSS_ROT_CLK_SRC] = &disp_cc_mdss_rot_clk_src.clkr,
-	[DISP_CC_MDSS_RSCC_AHB_CLK] = &disp_cc_mdss_rscc_ahb_clk.clkr,
 	[DISP_CC_MDSS_RSCC_VSYNC_CLK] = &disp_cc_mdss_rscc_vsync_clk.clkr,
 	[DISP_CC_MDSS_VSYNC_CLK] = &disp_cc_mdss_vsync_clk.clkr,
 	[DISP_CC_MDSS_VSYNC_CLK_SRC] = &disp_cc_mdss_vsync_clk_src.clkr,