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Date:   Tue, 2 Feb 2021 10:52:41 -0700
From:   Mathieu Poirier <mathieu.poirier@linaro.org>
To:     Anshuman Khandual <anshuman.khandual@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org, coresight@lists.linaro.org,
        suzuki.poulose@arm.com, mike.leach@linaro.org,
        lcherian@marvell.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V3 04/14] coresight: ete: Add support for ETE sysreg
 access
Message-ID: <20210202175241.GC1536093@xps15>
References: <1611737738-1493-1-git-send-email-anshuman.khandual@arm.com>
 <1611737738-1493-5-git-send-email-anshuman.khandual@arm.com>
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On Wed, Jan 27, 2021 at 02:25:28PM +0530, Anshuman Khandual wrote:
> From: Suzuki K Poulose <suzuki.poulose@arm.com>
> 
> Add support for handling the system registers for Embedded Trace
> Extensions (ETE). ETE shares most of the registers with ETMv4 except
> for some and also adds some new registers. Re-arrange the ETMv4x list
> to share the common definitions and add the ETE sysreg support.
> 
> Cc: Mike Leach <mike.leach@linaro.org>
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> ---
>  drivers/hwtracing/coresight/coresight-etm4x-core.c | 32 +++++++++++++
>  drivers/hwtracing/coresight/coresight-etm4x.h      | 52 ++++++++++++++++++----
>  2 files changed, 75 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 9edf8be..9e92d2a 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -114,6 +114,38 @@ void etm4x_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
>  	}
>  }
>  
> +u64 ete_sysreg_read(u32 offset, bool _relaxed, bool _64bit)
> +{
> +	u64 res = 0;
> +
> +	switch (offset) {
> +	ETE_READ_CASES(res)
> +	default :
> +		WARN_ONCE(1, "ete: trying to read unsupported register @%x\n",
> +			 offset);

Alignment

> +	}
> +
> +	if (!_relaxed)
> +		__iormb(res);	/* Imitate the !relaxed I/O helpers */
> +
> +	return res;
> +}
> +
> +void ete_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
> +{
> +	if (!_relaxed)
> +		__iowmb();	/* Imitate the !relaxed I/O helpers */
> +	if (!_64bit)
> +		val &= GENMASK(31, 0);
> +
> +	switch (offset) {
> +	ETE_WRITE_CASES(val)
> +	default :
> +		WARN_ONCE(1, "ete: trying to write to unsupported register @%x\n",
> +			offset);

Alignment

> +	}
> +}

The etm4x_sysreg_xyz() equivalent of these use a pr_warn_ratelimited() rather
than a WARN_ONE().  

With that:

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>

> +
>  static void etm_detect_os_lock(struct etmv4_drvdata *drvdata,
>  			       struct csdev_access *csa)
>  {
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
> index 0e86eba..ca24ac5 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x.h
> +++ b/drivers/hwtracing/coresight/coresight-etm4x.h
> @@ -29,6 +29,7 @@
>  #define TRCAUXCTLR			0x018
>  #define TRCEVENTCTL0R			0x020
>  #define TRCEVENTCTL1R			0x024
> +#define TRCRSR				0x028
>  #define TRCSTALLCTLR			0x02C
>  #define TRCTSCTLR			0x030
>  #define TRCSYNCPR			0x034
> @@ -49,6 +50,7 @@
>  #define TRCSEQRSTEVR			0x118
>  #define TRCSEQSTR			0x11C
>  #define TRCEXTINSELR			0x120
> +#define TRCEXTINSELRn(n)		(0x120 + (n * 4)) /* n = 0-3 */
>  #define TRCCNTRLDVRn(n)			(0x140 + (n * 4)) /* n = 0-3 */
>  #define TRCCNTCTLRn(n)			(0x150 + (n * 4)) /* n = 0-3 */
>  #define TRCCNTVRn(n)			(0x160 + (n * 4)) /* n = 0-3 */
> @@ -160,10 +162,22 @@
>  #define CASE_NOP(__unused, x)					\
>  	case (x):	/* fall through */
>  
> +#define ETE_ONLY_SYSREG_LIST(op, val)		\
> +	CASE_##op((val), TRCRSR)		\
> +	CASE_##op((val), TRCEXTINSELRn(1))	\
> +	CASE_##op((val), TRCEXTINSELRn(2))	\
> +	CASE_##op((val), TRCEXTINSELRn(3))
> +
>  /* List of registers accessible via System instructions */
> -#define ETM_SYSREG_LIST(op, val)		\
> -	CASE_##op((val), TRCPRGCTLR)		\
> +#define ETM4x_ONLY_SYSREG_LIST(op, val)		\
>  	CASE_##op((val), TRCPROCSELR)		\
> +	CASE_##op((val), TRCVDCTLR)		\
> +	CASE_##op((val), TRCVDSACCTLR)		\
> +	CASE_##op((val), TRCVDARCCTLR)		\
> +	CASE_##op((val), TRCOSLAR)
> +
> +#define ETM_COMMON_SYSREG_LIST(op, val)		\
> +	CASE_##op((val), TRCPRGCTLR)		\
>  	CASE_##op((val), TRCSTATR)		\
>  	CASE_##op((val), TRCCONFIGR)		\
>  	CASE_##op((val), TRCAUXCTLR)		\
> @@ -180,9 +194,6 @@
>  	CASE_##op((val), TRCVIIECTLR)		\
>  	CASE_##op((val), TRCVISSCTLR)		\
>  	CASE_##op((val), TRCVIPCSSCTLR)		\
> -	CASE_##op((val), TRCVDCTLR)		\
> -	CASE_##op((val), TRCVDSACCTLR)		\
> -	CASE_##op((val), TRCVDARCCTLR)		\
>  	CASE_##op((val), TRCSEQEVRn(0))		\
>  	CASE_##op((val), TRCSEQEVRn(1))		\
>  	CASE_##op((val), TRCSEQEVRn(2))		\
> @@ -277,7 +288,6 @@
>  	CASE_##op((val), TRCSSPCICRn(5))	\
>  	CASE_##op((val), TRCSSPCICRn(6))	\
>  	CASE_##op((val), TRCSSPCICRn(7))	\
> -	CASE_##op((val), TRCOSLAR)		\
>  	CASE_##op((val), TRCOSLSR)		\
>  	CASE_##op((val), TRCACVRn(0))		\
>  	CASE_##op((val), TRCACVRn(1))		\
> @@ -369,12 +379,36 @@
>  	CASE_##op((val), TRCPIDR2)		\
>  	CASE_##op((val), TRCPIDR3)
>  
> -#define ETM4x_READ_SYSREG_CASES(res)	ETM_SYSREG_LIST(READ, (res))
> -#define ETM4x_WRITE_SYSREG_CASES(val)	ETM_SYSREG_LIST(WRITE, (val))
> +#define ETM4x_READ_SYSREG_CASES(res)		\
> +	ETM_COMMON_SYSREG_LIST(READ, (res))	\
> +	ETM4x_ONLY_SYSREG_LIST(READ, (res))
> +
> +#define ETM4x_WRITE_SYSREG_CASES(val)		\
> +	ETM_COMMON_SYSREG_LIST(WRITE, (val))	\
> +	ETM4x_ONLY_SYSREG_LIST(WRITE, (val))
> +
> +#define ETM_COMMON_SYSREG_LIST_CASES		\
> +	ETM_COMMON_SYSREG_LIST(NOP, __unused)
> +
> +#define ETM4x_SYSREG_LIST_CASES			\
> +	ETM_COMMON_SYSREG_LIST_CASES		\
> +	ETM4x_ONLY_SYSREG_LIST(NOP, __unused)
>  
> -#define ETM4x_SYSREG_LIST_CASES		ETM_SYSREG_LIST(NOP, __unused)
>  #define ETM4x_MMAP_LIST_CASES		ETM_MMAP_LIST(NOP, __unused)
>  
> +/* ETE only supports system register access */
> +#define ETE_READ_CASES(res)			\
> +	ETM_COMMON_SYSREG_LIST(READ, (res))	\
> +	ETE_ONLY_SYSREG_LIST(READ, (res))
> +
> +#define ETE_WRITE_CASES(val)			\
> +	ETM_COMMON_SYSREG_LIST(WRITE, (val))	\
> +	ETE_ONLY_SYSREG_LIST(WRITE, (val))
> +
> +#define ETE_ONLY_SYSREG_LIST_CASES		\
> +	ETM_COMMON_SYSREG_LIST_CASES		\
> +	ETE_ONLY_SYSREG_LIST(NOP, __unused)
> +
>  #define read_etm4x_sysreg_offset(offset, _64bit)				\
>  	({									\
>  		u64 __val;							\
> -- 
> 2.7.4
>