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[PATCH v12 3/9] firmware: qcom: scm: Modify only the download bits in TCSR register

Mukesh Ojha posted 9 patches 1 year, 10 months ago
[PATCH v12 3/9] firmware: qcom: scm: Modify only the download bits in TCSR register
Posted by Mukesh Ojha 1 year, 10 months ago 
Crashdump collection is done based on DLOAD bits of TCSR register.
To retain other bits, scm driver need to read the register and
modify only the DLOAD bits, as other bits in TCSR may have their
own significance.

Co-developed-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
Signed-off-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
Tested-by: Kathiravan Thirumoorthy <quic_kathirav@quicinc.com> # IPQ9574 and IPQ5332
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Elliot Berman <quic_eberman@quicinc.com>
---
 drivers/firmware/qcom/qcom_scm.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index 8f766fce5f7c..bd6bfdf2d828 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -4,6 +4,8 @@
  */
 
 #include <linux/arm-smccc.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
 #include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/cpumask.h>
@@ -114,6 +116,12 @@ static const u8 qcom_scm_cpu_warm_bits[QCOM_SCM_BOOT_MAX_CPUS] = {
 #define QCOM_SMC_WAITQ_FLAG_WAKE_ONE	BIT(0)
 #define QCOM_SMC_WAITQ_FLAG_WAKE_ALL	BIT(1)
 
+#define QCOM_DLOAD_MASK		GENMASK(5, 4)
+enum qcom_dload_mode {
+	QCOM_DLOAD_NODUMP	= 0,
+	QCOM_DLOAD_FULLDUMP	= 1,
+};
+
 static const char * const qcom_scm_convention_names[] = {
 	[SMC_CONVENTION_UNKNOWN] = "unknown",
 	[SMC_CONVENTION_ARM_32] = "smc arm 32",
@@ -531,6 +539,7 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
 
 static void qcom_scm_set_download_mode(bool enable)
 {
+	u32 val = enable ? QCOM_DLOAD_FULLDUMP : QCOM_DLOAD_NODUMP;
 	bool avail;
 	int ret = 0;
 
@@ -540,8 +549,9 @@ static void qcom_scm_set_download_mode(bool enable)
 	if (avail) {
 		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
 	} else if (__scm->dload_mode_addr) {
-		ret = qcom_scm_io_writel(__scm->dload_mode_addr,
-				enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
+		ret = qcom_scm_io_rmw(__scm->dload_mode_addr,
+				      QCOM_DLOAD_MASK,
+				      FIELD_PREP(QCOM_DLOAD_MASK, val));
 	} else {
 		dev_err(__scm->dev,
 			"No available mechanism for setting download mode\n");
-- 
2.43.0.254.ga26002b62827
Re: [PATCH v12 3/9] firmware: qcom: scm: Modify only the download bits in TCSR register
Posted by Bjorn Andersson 1 year, 9 months ago 
On Tue, Feb 27, 2024 at 09:23:02PM +0530, Mukesh Ojha wrote:
> Crashdump collection is done based on DLOAD bits of TCSR register.
> To retain other bits, scm driver need to read the register and
> modify only the DLOAD bits, as other bits in TCSR may have their
> own significance.
> 
> Co-developed-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
> Signed-off-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
> Tested-by: Kathiravan Thirumoorthy <quic_kathirav@quicinc.com> # IPQ9574 and IPQ5332
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Reviewed-by: Elliot Berman <quic_eberman@quicinc.com>
> ---
>  drivers/firmware/qcom/qcom_scm.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
> index 8f766fce5f7c..bd6bfdf2d828 100644
> --- a/drivers/firmware/qcom/qcom_scm.c
> +++ b/drivers/firmware/qcom/qcom_scm.c
> @@ -4,6 +4,8 @@
>   */
>  
>  #include <linux/arm-smccc.h>
> +#include <linux/bitfield.h>
> +#include <linux/bits.h>
>  #include <linux/clk.h>
>  #include <linux/completion.h>
>  #include <linux/cpumask.h>
> @@ -114,6 +116,12 @@ static const u8 qcom_scm_cpu_warm_bits[QCOM_SCM_BOOT_MAX_CPUS] = {
>  #define QCOM_SMC_WAITQ_FLAG_WAKE_ONE	BIT(0)
>  #define QCOM_SMC_WAITQ_FLAG_WAKE_ALL	BIT(1)
>  
> +#define QCOM_DLOAD_MASK		GENMASK(5, 4)
> +enum qcom_dload_mode {
> +	QCOM_DLOAD_NODUMP	= 0,
> +	QCOM_DLOAD_FULLDUMP	= 1,

These values are not enumerations, they represent fixed/defined values
in the interface. As such it's appropriate to use #define.

Regards,
Bjorn

> +};
> +
>  static const char * const qcom_scm_convention_names[] = {
>  	[SMC_CONVENTION_UNKNOWN] = "unknown",
>  	[SMC_CONVENTION_ARM_32] = "smc arm 32",
> @@ -531,6 +539,7 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
>  
>  static void qcom_scm_set_download_mode(bool enable)
>  {
> +	u32 val = enable ? QCOM_DLOAD_FULLDUMP : QCOM_DLOAD_NODUMP;
>  	bool avail;
>  	int ret = 0;
>  
> @@ -540,8 +549,9 @@ static void qcom_scm_set_download_mode(bool enable)
>  	if (avail) {
>  		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
>  	} else if (__scm->dload_mode_addr) {
> -		ret = qcom_scm_io_writel(__scm->dload_mode_addr,
> -				enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
> +		ret = qcom_scm_io_rmw(__scm->dload_mode_addr,
> +				      QCOM_DLOAD_MASK,
> +				      FIELD_PREP(QCOM_DLOAD_MASK, val));
>  	} else {
>  		dev_err(__scm->dev,
>  			"No available mechanism for setting download mode\n");
> -- 
> 2.43.0.254.ga26002b62827
>
Re: [PATCH v12 3/9] firmware: qcom: scm: Modify only the download bits in TCSR register
Posted by Mukesh Ojha 1 year, 9 months ago 

On 3/3/2024 12:43 AM, Bjorn Andersson wrote:
> On Tue, Feb 27, 2024 at 09:23:02PM +0530, Mukesh Ojha wrote:
>> Crashdump collection is done based on DLOAD bits of TCSR register.
>> To retain other bits, scm driver need to read the register and
>> modify only the DLOAD bits, as other bits in TCSR may have their
>> own significance.
>>
>> Co-developed-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
>> Signed-off-by: Poovendhan Selvaraj <quic_poovendh@quicinc.com>
>> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com>
>> Tested-by: Kathiravan Thirumoorthy <quic_kathirav@quicinc.com> # IPQ9574 and IPQ5332
>> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> Reviewed-by: Elliot Berman <quic_eberman@quicinc.com>
>> ---
>>   drivers/firmware/qcom/qcom_scm.c | 14 ++++++++++++--
>>   1 file changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
>> index 8f766fce5f7c..bd6bfdf2d828 100644
>> --- a/drivers/firmware/qcom/qcom_scm.c
>> +++ b/drivers/firmware/qcom/qcom_scm.c
>> @@ -4,6 +4,8 @@
>>    */
>>   
>>   #include <linux/arm-smccc.h>
>> +#include <linux/bitfield.h>
>> +#include <linux/bits.h>
>>   #include <linux/clk.h>
>>   #include <linux/completion.h>
>>   #include <linux/cpumask.h>
>> @@ -114,6 +116,12 @@ static const u8 qcom_scm_cpu_warm_bits[QCOM_SCM_BOOT_MAX_CPUS] = {
>>   #define QCOM_SMC_WAITQ_FLAG_WAKE_ONE	BIT(0)
>>   #define QCOM_SMC_WAITQ_FLAG_WAKE_ALL	BIT(1)
>>   
>> +#define QCOM_DLOAD_MASK		GENMASK(5, 4)
>> +enum qcom_dload_mode {
>> +	QCOM_DLOAD_NODUMP	= 0,
>> +	QCOM_DLOAD_FULLDUMP	= 1,
> 
> These values are not enumerations, they represent fixed/defined values
> in the interface. As such it's appropriate to use #define.
> 

Thanks for giving reasoning on why it should be #define and not enum.

-Mukesh

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