[PATCH v2 0/7] Apple A7-A11, T2 SoC cpufreq support

[PATCH v2 0/7] Apple A7-A11, T2 SoC cpufreq support

[Nick Chan]

This series add driver support for cpufreq Apple A7-A11, T2 SoCs.
Device Tree nodes will be included in another series.

Changes since v1:
- transition_latency is in ns, APPLE_DVFS_TRANSITION_TIMEOUT in us.
Multiply APPLE_DVFS_TRANSITION_TIMEOUT by 1000 before setting it as
transition_latency.

v1: https://lore.kernel.org/asahi/20241211112244.18393-1-towinchenmi@gmail.com/T

Nick Chan
---
Hector Martin (1):
  cpufreq: apple-soc: Drop setting the PS2 field on M2+

Nick Chan (6):
  dt-bindings: cpufreq: apple,cluster-cpufreq: Add A7-A11, T2
    compatibles
  cpufreq: apple-soc: Allow per-SoC configuration of APPLE_DVFS_CMD_PS1
  cpufreq: apple-soc: Use 32-bit read for status register
  cpufreq: apple-soc: Increase cluster switch timeout to 400us
  cpufreq: apple-soc: Set fallback transition latency to
    APPLE_DVFS_TRANSITION_TIMEOUT
  cpufreq: apple-soc: Add Apple A7-A8X SoC cpufreq support

 .../cpufreq/apple,cluster-cpufreq.yaml        | 10 +++-
 drivers/cpufreq/apple-soc-cpufreq.c           | 56 +++++++++++++++----
 2 files changed, 54 insertions(+), 12 deletions(-)


base-commit: fac04efc5c793dccbd07e2d59af9f90b7fc0dca4
-- 
2.47.1

[PATCH v2 1/7] dt-bindings: cpufreq: apple,cluster-cpufreq: Add A7-A11, T2 compatibles

[Nick Chan]

Add compatibles for Apple A7-A11, T2 SoCs.

Apple A7, A8, A8X gets the per-SoC compatible and the A7
"apple,s5l8960x-cluster-cpufreq" compatible.

Apple A9, A9X, A10, A10X, T2, A11 gets the per-SoC compatible, M1
"apple,t8103-cluster-cpufreq" compatible, then the
"apple,cluster-cpufreq" fallback compatible.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 .../bindings/cpufreq/apple,cluster-cpufreq.yaml        | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml b/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml
index 76cb9726660e..896276b8c6bb 100644
--- a/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml
+++ b/Documentation/devicetree/bindings/cpufreq/apple,cluster-cpufreq.yaml
@@ -24,9 +24,17 @@ properties:
               - apple,t8112-cluster-cpufreq
           - const: apple,cluster-cpufreq
       - items:
-          - const: apple,t6000-cluster-cpufreq
+          - enum:
+              - apple,s8000-cluster-cpufreq
+              - apple,t8010-cluster-cpufreq
+              - apple,t8015-cluster-cpufreq
+              - apple,t6000-cluster-cpufreq
           - const: apple,t8103-cluster-cpufreq
           - const: apple,cluster-cpufreq
+      - items:
+          - const: apple,t7000-cluster-cpufreq
+          - const: apple,s5l8960x-cluster-cpufreq
+      - const: apple,s5l8960x-cluster-cpufreq
 
   reg:
     maxItems: 1
-- 
2.47.1

[PATCH v2 2/7] cpufreq: apple-soc: Drop setting the PS2 field on M2+

[Nick Chan]

From: Hector Martin <marcan@marcan.st>

Newer device do not use this. It is not known what this field does,
but change the behavior to be same as macOS to be safe.

Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index 4dcacab9b4bf..ad6c7b8f290c 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -25,7 +25,7 @@
 #define APPLE_DVFS_CMD			0x20
 #define APPLE_DVFS_CMD_BUSY		BIT(31)
 #define APPLE_DVFS_CMD_SET		BIT(25)
-#define APPLE_DVFS_CMD_PS2		GENMASK(16, 12)
+#define APPLE_DVFS_CMD_PS2		GENMASK(15, 12)
 #define APPLE_DVFS_CMD_PS1		GENMASK(4, 0)
 
 /* Same timebase as CPU counter (24MHz) */
@@ -55,6 +55,7 @@
 #define APPLE_DVFS_TRANSITION_TIMEOUT 100
 
 struct apple_soc_cpufreq_info {
+	bool has_ps2;
 	u64 max_pstate;
 	u64 cur_pstate_mask;
 	u64 cur_pstate_shift;
@@ -69,18 +70,21 @@ struct apple_cpu_priv {
 static struct cpufreq_driver apple_soc_cpufreq_driver;
 
 static const struct apple_soc_cpufreq_info soc_t8103_info = {
+	.has_ps2 = true,
 	.max_pstate = 15,
 	.cur_pstate_mask = APPLE_DVFS_STATUS_CUR_PS_T8103,
 	.cur_pstate_shift = APPLE_DVFS_STATUS_CUR_PS_SHIFT_T8103,
 };
 
 static const struct apple_soc_cpufreq_info soc_t8112_info = {
+	.has_ps2 = false,
 	.max_pstate = 31,
 	.cur_pstate_mask = APPLE_DVFS_STATUS_CUR_PS_T8112,
 	.cur_pstate_shift = APPLE_DVFS_STATUS_CUR_PS_SHIFT_T8112,
 };
 
 static const struct apple_soc_cpufreq_info soc_default_info = {
+	.has_ps2 = false,
 	.max_pstate = 15,
 	.cur_pstate_mask = 0, /* fallback */
 };
@@ -148,9 +152,12 @@ static int apple_soc_cpufreq_set_target(struct cpufreq_policy *policy,
 		return -EIO;
 	}
 
-	reg &= ~(APPLE_DVFS_CMD_PS1 | APPLE_DVFS_CMD_PS2);
+	reg &= ~APPLE_DVFS_CMD_PS1;
 	reg |= FIELD_PREP(APPLE_DVFS_CMD_PS1, pstate);
-	reg |= FIELD_PREP(APPLE_DVFS_CMD_PS2, pstate);
+	if (priv->info->has_ps2) {
+		reg &= ~APPLE_DVFS_CMD_PS2;
+		reg |= FIELD_PREP(APPLE_DVFS_CMD_PS2, pstate);
+	}
 	reg |= APPLE_DVFS_CMD_SET;
 
 	writeq_relaxed(reg, priv->reg_base + APPLE_DVFS_CMD);
-- 
2.47.1

[PATCH v2 3/7] cpufreq: apple-soc: Allow per-SoC configuration of APPLE_DVFS_CMD_PS1

[Nick Chan]

Support for SoC that has a different APPLE_DVFS_CMD_PS1 will be added soon,
so modify the driver first to allow it to be configured per-SoC.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index ad6c7b8f290c..90e34105b50b 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -27,6 +27,7 @@
 #define APPLE_DVFS_CMD_SET		BIT(25)
 #define APPLE_DVFS_CMD_PS2		GENMASK(15, 12)
 #define APPLE_DVFS_CMD_PS1		GENMASK(4, 0)
+#define APPLE_DVFS_CMD_PS1_SHIFT	0
 
 /* Same timebase as CPU counter (24MHz) */
 #define APPLE_DVFS_LAST_CHG_TIME	0x38
@@ -59,6 +60,8 @@ struct apple_soc_cpufreq_info {
 	u64 max_pstate;
 	u64 cur_pstate_mask;
 	u64 cur_pstate_shift;
+	u64 ps1_mask;
+	u64 ps1_shift;
 };
 
 struct apple_cpu_priv {
@@ -74,6 +77,8 @@ static const struct apple_soc_cpufreq_info soc_t8103_info = {
 	.max_pstate = 15,
 	.cur_pstate_mask = APPLE_DVFS_STATUS_CUR_PS_T8103,
 	.cur_pstate_shift = APPLE_DVFS_STATUS_CUR_PS_SHIFT_T8103,
+	.ps1_mask = APPLE_DVFS_CMD_PS1,
+	.ps1_shift = APPLE_DVFS_CMD_PS1_SHIFT,
 };
 
 static const struct apple_soc_cpufreq_info soc_t8112_info = {
@@ -81,12 +86,16 @@ static const struct apple_soc_cpufreq_info soc_t8112_info = {
 	.max_pstate = 31,
 	.cur_pstate_mask = APPLE_DVFS_STATUS_CUR_PS_T8112,
 	.cur_pstate_shift = APPLE_DVFS_STATUS_CUR_PS_SHIFT_T8112,
+	.ps1_mask = APPLE_DVFS_CMD_PS1,
+	.ps1_shift = APPLE_DVFS_CMD_PS1_SHIFT,
 };
 
 static const struct apple_soc_cpufreq_info soc_default_info = {
 	.has_ps2 = false,
 	.max_pstate = 15,
 	.cur_pstate_mask = 0, /* fallback */
+	.ps1_mask = APPLE_DVFS_CMD_PS1,
+	.ps1_shift = APPLE_DVFS_CMD_PS1_SHIFT,
 };
 
 static const struct of_device_id apple_soc_cpufreq_of_match[] __maybe_unused = {
@@ -152,8 +161,8 @@ static int apple_soc_cpufreq_set_target(struct cpufreq_policy *policy,
 		return -EIO;
 	}
 
-	reg &= ~APPLE_DVFS_CMD_PS1;
-	reg |= FIELD_PREP(APPLE_DVFS_CMD_PS1, pstate);
+	reg &= ~priv->info->ps1_mask;
+	reg |= pstate << priv->info->ps1_shift;
 	if (priv->info->has_ps2) {
 		reg &= ~APPLE_DVFS_CMD_PS2;
 		reg |= FIELD_PREP(APPLE_DVFS_CMD_PS2, pstate);
-- 
2.47.1

[PATCH v2 4/7] cpufreq: apple-soc: Use 32-bit read for status register

[Nick Chan]

Apple A7-A9(X) SoCs requires 32-bit reads on the status register. Newer
SoCs accepts 32-bit reads on the status register as well.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index 90e34105b50b..b27d261fe5a6 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -122,7 +122,7 @@ static unsigned int apple_soc_cpufreq_get_rate(unsigned int cpu)
 	unsigned int pstate;
 
 	if (priv->info->cur_pstate_mask) {
-		u64 reg = readq_relaxed(priv->reg_base + APPLE_DVFS_STATUS);
+		u32 reg = readl_relaxed(priv->reg_base + APPLE_DVFS_STATUS);
 
 		pstate = (reg & priv->info->cur_pstate_mask) >>  priv->info->cur_pstate_shift;
 	} else {
-- 
2.47.1

[PATCH v2 5/7] cpufreq: apple-soc: Increase cluster switch timeout to 400us

[Nick Chan]

Apple A11 SoC takes a long time to switch. Maximum switch time
observed is 345us, so increase the cluster switch timeout to 400us
to be safe.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index b27d261fe5a6..94e57f055a5f 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -53,7 +53,7 @@
 #define APPLE_DVFS_PLL_FACTOR_MULT	GENMASK(31, 16)
 #define APPLE_DVFS_PLL_FACTOR_DIV	GENMASK(15, 0)
 
-#define APPLE_DVFS_TRANSITION_TIMEOUT 100
+#define APPLE_DVFS_TRANSITION_TIMEOUT 400
 
 struct apple_soc_cpufreq_info {
 	bool has_ps2;
-- 
2.47.1

[PATCH v2 6/7] cpufreq: apple-soc: Set fallback transition latency to APPLE_DVFS_TRANSITION_TIMEOUT

[Nick Chan]

The driver already assumes transitions will not take longer than
APPLE_DVFS_TRANSITION_TIMEOUT in apple_soc_cpufreq_set_target(), so it
makes little sense to set CPUFREQ_ETERNAL as the transition latency
when the transistion latency is not given by the opp-table.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index 94e57f055a5f..c9f31a3653e2 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -291,7 +291,7 @@ static int apple_soc_cpufreq_init(struct cpufreq_policy *policy)
 
 	transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev);
 	if (!transition_latency)
-		transition_latency = CPUFREQ_ETERNAL;
+		transition_latency = APPLE_DVFS_TRANSITION_TIMEOUT * 1000;
 
 	policy->cpuinfo.transition_latency = transition_latency;
 	policy->dvfs_possible_from_any_cpu = true;
-- 
2.47.1

[PATCH v2 7/7] cpufreq: apple-soc: Add Apple A7-A8X SoC cpufreq support

[Nick Chan]

These SoCs only use 3 bits for p-states, and have a different
APPLE_DVFS_CMD_PS1 mask value.

Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
 drivers/cpufreq/apple-soc-cpufreq.c | 30 +++++++++++++++++++++++------
 1 file changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
index c9f31a3653e2..c3a6dd8ae22a 100644
--- a/drivers/cpufreq/apple-soc-cpufreq.c
+++ b/drivers/cpufreq/apple-soc-cpufreq.c
@@ -22,12 +22,14 @@
 #include <linux/pm_opp.h>
 #include <linux/slab.h>
 
-#define APPLE_DVFS_CMD			0x20
-#define APPLE_DVFS_CMD_BUSY		BIT(31)
-#define APPLE_DVFS_CMD_SET		BIT(25)
-#define APPLE_DVFS_CMD_PS2		GENMASK(15, 12)
-#define APPLE_DVFS_CMD_PS1		GENMASK(4, 0)
-#define APPLE_DVFS_CMD_PS1_SHIFT	0
+#define APPLE_DVFS_CMD				0x20
+#define APPLE_DVFS_CMD_BUSY			BIT(31)
+#define APPLE_DVFS_CMD_SET			BIT(25)
+#define APPLE_DVFS_CMD_PS1_S5L8960X		GENMASK(24, 22)
+#define APPLE_DVFS_CMD_PS1_S5L8960X_SHIFT	22
+#define APPLE_DVFS_CMD_PS2			GENMASK(15, 12)
+#define APPLE_DVFS_CMD_PS1			GENMASK(4, 0)
+#define APPLE_DVFS_CMD_PS1_SHIFT		0
 
 /* Same timebase as CPU counter (24MHz) */
 #define APPLE_DVFS_LAST_CHG_TIME	0x38
@@ -36,6 +38,9 @@
  * Apple ran out of bits and had to shift this in T8112...
  */
 #define APPLE_DVFS_STATUS			0x50
+#define APPLE_DVFS_STATUS_CUR_PS_S5L8960X	GENMASK(5, 3)
+#define APPLE_DVFS_STATUS_CUR_PS_SHIFT_S5L8960X	3
+#define APPLE_DVFS_STATUS_TGT_PS_S5L8960X	GENMASK(2, 0)
 #define APPLE_DVFS_STATUS_CUR_PS_T8103		GENMASK(7, 4)
 #define APPLE_DVFS_STATUS_CUR_PS_SHIFT_T8103	4
 #define APPLE_DVFS_STATUS_TGT_PS_T8103		GENMASK(3, 0)
@@ -72,6 +77,15 @@ struct apple_cpu_priv {
 
 static struct cpufreq_driver apple_soc_cpufreq_driver;
 
+static const struct apple_soc_cpufreq_info soc_s5l8960x_info = {
+	.has_ps2 = false,
+	.max_pstate = 7,
+	.cur_pstate_mask = APPLE_DVFS_STATUS_CUR_PS_S5L8960X,
+	.cur_pstate_shift = APPLE_DVFS_STATUS_CUR_PS_SHIFT_S5L8960X,
+	.ps1_mask = APPLE_DVFS_CMD_PS1_S5L8960X,
+	.ps1_shift = APPLE_DVFS_CMD_PS1_S5L8960X_SHIFT,
+};
+
 static const struct apple_soc_cpufreq_info soc_t8103_info = {
 	.has_ps2 = true,
 	.max_pstate = 15,
@@ -99,6 +113,10 @@ static const struct apple_soc_cpufreq_info soc_default_info = {
 };
 
 static const struct of_device_id apple_soc_cpufreq_of_match[] __maybe_unused = {
+	{
+		.compatible = "apple,s5l8960x-cluster-cpufreq",
+		.data = &soc_s5l8960x_info,
+	},
 	{
 		.compatible = "apple,t8103-cluster-cpufreq",
 		.data = &soc_t8103_info,
-- 
2.47.1

Re: [PATCH v2 1/7] dt-bindings: cpufreq: apple,cluster-cpufreq: Add A7-A11, T2 compatibles

[Krzysztof Kozlowski]

On Thu, Dec 12, 2024 at 03:03:00PM +0800, Nick Chan wrote:
> Add compatibles for Apple A7-A11, T2 SoCs.
> 
> Apple A7, A8, A8X gets the per-SoC compatible and the A7
> "apple,s5l8960x-cluster-cpufreq" compatible.
> 
> Apple A9, A9X, A10, A10X, T2, A11 gets the per-SoC compatible, M1
> "apple,t8103-cluster-cpufreq" compatible, then the
> "apple,cluster-cpufreq" fallback compatible.
> 
> Signed-off-by: Nick Chan <towinchenmi@gmail.com>

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH v2 6/7] cpufreq: apple-soc: Set fallback transition latency to APPLE_DVFS_TRANSITION_TIMEOUT

[Christian Loehle]

On 12/12/24 07:03, Nick Chan wrote:
> The driver already assumes transitions will not take longer than
> APPLE_DVFS_TRANSITION_TIMEOUT in apple_soc_cpufreq_set_target(), so it
> makes little sense to set CPUFREQ_ETERNAL as the transition latency
> when the transistion latency is not given by the opp-table.
> 
> Signed-off-by: Nick Chan <towinchenmi@gmail.com>

Reviewed-by: Christian Loehle <christian.loehle@arm.com>

> ---
>  drivers/cpufreq/apple-soc-cpufreq.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
> index 94e57f055a5f..c9f31a3653e2 100644
> --- a/drivers/cpufreq/apple-soc-cpufreq.c
> +++ b/drivers/cpufreq/apple-soc-cpufreq.c
> @@ -291,7 +291,7 @@ static int apple_soc_cpufreq_init(struct cpufreq_policy *policy)
>  
>  	transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev);
>  	if (!transition_latency)
> -		transition_latency = CPUFREQ_ETERNAL;
> +		transition_latency = APPLE_DVFS_TRANSITION_TIMEOUT * 1000;
>  
>  	policy->cpuinfo.transition_latency = transition_latency;
>  	policy->dvfs_possible_from_any_cpu = true;

Re: [PATCH v2 6/7] cpufreq: apple-soc: Set fallback transition latency to APPLE_DVFS_TRANSITION_TIMEOUT

[Christian Loehle]

On 12/12/24 11:06, Christian Loehle wrote:
> On 12/12/24 07:03, Nick Chan wrote:
>> The driver already assumes transitions will not take longer than
>> APPLE_DVFS_TRANSITION_TIMEOUT in apple_soc_cpufreq_set_target(), so it
>> makes little sense to set CPUFREQ_ETERNAL as the transition latency
>> when the transistion latency is not given by the opp-table.
>>
>> Signed-off-by: Nick Chan <towinchenmi@gmail.com>
> 
> Reviewed-by: Christian Loehle <christian.loehle@arm.com>
> 
>> ---
>>  drivers/cpufreq/apple-soc-cpufreq.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/apple-soc-cpufreq.c b/drivers/cpufreq/apple-soc-cpufreq.c
>> index 94e57f055a5f..c9f31a3653e2 100644
>> --- a/drivers/cpufreq/apple-soc-cpufreq.c
>> +++ b/drivers/cpufreq/apple-soc-cpufreq.c
>> @@ -291,7 +291,7 @@ static int apple_soc_cpufreq_init(struct cpufreq_policy *policy)
>>  
>>  	transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev);
>>  	if (!transition_latency)
>> -		transition_latency = CPUFREQ_ETERNAL;
>> +		transition_latency = APPLE_DVFS_TRANSITION_TIMEOUT * 1000;

s/1000/NSEC_PER_USEC would have been the cleaner choice in case you respin.

>>  
>>  	policy->cpuinfo.transition_latency = transition_latency;
>>  	policy->dvfs_possible_from_any_cpu = true;
> 
>