[PATCH v2 1/5] lib: sbi: Remove redundant SBI_HART_HAS_PMP feature

[Alistair Francis]

On Mon, 2020-08-24 at 19:22 +0530, Anup Patel wrote:
> The SBI_HART_HAS_PMP feature is redundant because we already
> have number of PMP regions returned by sbi_hart_pmp_count().
> 
> Checking whether PMP is supported for a HART can be simply done
> by checking non-zero value returned by sbi_hart_pmp_count().
> 
> Signed-off-by: Anup Patel <anup.patel at wdc.com>

Reviewed-by: Alistair Francis <alistair.francis at wdc.com>

Alistair

> ---
>  include/sbi/sbi_hart.h    |  8 +++-----
>  lib/sbi/sbi_hart.c        | 15 +--------------
>  lib/utils/fdt/fdt_fixup.c |  2 +-
>  3 files changed, 5 insertions(+), 20 deletions(-)
> 
> diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h
> index 51c2c35..c2ea686 100644
> --- a/include/sbi/sbi_hart.h
> +++ b/include/sbi/sbi_hart.h
> @@ -14,14 +14,12 @@
>  
>  /** Possible feature flags of a hart */
>  enum sbi_hart_features {
> -	/** Hart has PMP support */
> -	SBI_HART_HAS_PMP = (1 << 0),
>  	/** Hart has S-mode counter enable */
> -	SBI_HART_HAS_SCOUNTEREN = (1 << 1),
> +	SBI_HART_HAS_SCOUNTEREN = (1 << 0),
>  	/** Hart has M-mode counter enable */
> -	SBI_HART_HAS_MCOUNTEREN = (1 << 2),
> +	SBI_HART_HAS_MCOUNTEREN = (1 << 1),
>  	/** HART has timer csr implementation in hardware */
> -	SBI_HART_HAS_TIME = (1 << 3),
> +	SBI_HART_HAS_TIME = (1 << 2),
>  
>  	/** Last index of Hart features*/
>  	SBI_HART_HAS_LAST_FEATURE = SBI_HART_HAS_TIME,
> diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
> index fa20bd2..80ed86a 100644
> --- a/lib/sbi/sbi_hart.c
> +++ b/lib/sbi/sbi_hart.c
> @@ -158,9 +158,6 @@ void sbi_hart_pmp_dump(struct sbi_scratch
> *scratch)
>  	unsigned long prot, addr, size;
>  	unsigned int i, pmp_count;
>  
> -	if (!sbi_hart_has_feature(scratch, SBI_HART_HAS_PMP))
> -		return;
> -
>  	pmp_count = sbi_hart_pmp_count(scratch);
>  	for (i = 0; i < pmp_count; i++) {
>  		pmp_get(i, &prot, &addr, &size);
> @@ -190,9 +187,6 @@ int sbi_hart_pmp_check_addr(struct sbi_scratch
> *scratch, unsigned long addr,
>  	unsigned long prot, size, tempaddr;
>  	unsigned int i, pmp_count;
>  
> -	if (!sbi_hart_has_feature(scratch, SBI_HART_HAS_PMP))
> -		return SBI_OK;
> -
>  	pmp_count = sbi_hart_pmp_count(scratch);
>  	for (i = 0; i < pmp_count; i++) {
>  		pmp_get(i, &prot, &tempaddr, &size);
> @@ -213,7 +207,7 @@ static int pmp_init(struct sbi_scratch *scratch,
> u32 hartid)
>  	ulong prot, addr, log2size;
>  	const struct sbi_platform *plat = sbi_platform_ptr(scratch);
>  
> -	if (!sbi_hart_has_feature(scratch, SBI_HART_HAS_PMP))
> +	if (!sbi_hart_pmp_count(scratch))
>  		return 0;
>  
>  	/* Firmware PMP region to protect OpenSBI firmware */
> @@ -276,9 +270,6 @@ static inline char
> *sbi_hart_feature_id2string(unsigned long feature)
>  		return NULL;
>  
>  	switch (feature) {
> -	case SBI_HART_HAS_PMP:
> -		fstr = "pmp";
> -		break;
>  	case SBI_HART_HAS_SCOUNTEREN:
>  		fstr = "scounteren";
>  		break;
> @@ -375,10 +366,6 @@ static void hart_detect_features(struct
> sbi_scratch *scratch)
>  	__detect_pmp(CSR_PMPADDR15);
>  #undef __detect_pmp
>  
> -	/* Set hart PMP feature if we have at least one PMP region */
> -	if (hfeatures->pmp_count)
> -		hfeatures->features |= SBI_HART_HAS_PMP;
> -
>  	/* Detect if hart supports SCOUNTEREN feature */
>  	trap.cause = 0;
>  	val = csr_read_allowed(CSR_SCOUNTEREN, (unsigned long)&trap);
> diff --git a/lib/utils/fdt/fdt_fixup.c b/lib/utils/fdt/fdt_fixup.c
> index a3bccae..4da7397 100644
> --- a/lib/utils/fdt/fdt_fixup.c
> +++ b/lib/utils/fdt/fdt_fixup.c
> @@ -199,7 +199,7 @@ int fdt_reserved_memory_fixup(void *fdt)
>  	 * With above assumption, we create child nodes directly.
>  	 */
>  
> -	if (!sbi_hart_has_feature(scratch, SBI_HART_HAS_PMP)) {
> +	if (!sbi_hart_pmp_count(scratch)) {
>  		/*
>  		 * Update the DT with firmware start & size even if PMP
> is not
>  		 * supported. This makes sure that supervisor OS is
> always