[PATCH 2/5] lib: sbi: Allow specifying mode in sbi_hart_pmp_check_addr() API
Atish Patra
atishp at atishpatra.org
Tue Sep 15 03:32:09 EDT 2020
On Wed, Sep 9, 2020 at 7:51 AM Anup Patel <anup.patel at wdc.com> wrote:
>
> We extend sbi_hart_pmp_check_addr() API so that users can specify
> privilege mode of the address for checking PMP access permissions.
>
> To achieve this, we end-up converting "unsigned long *size" parameter
> to "unsigned long *log2len" for pmp_get() implementation so that we
> can deal with regions of "1UL << __riscv_xlen" size in a special case
> in sbi_hart_pmp_check_addr() implementation.
>
> Signed-off-by: Anup Patel <anup.patel at wdc.com>
> ---
> include/sbi/riscv_asm.h | 2 +-
> include/sbi/sbi_hart.h | 3 ++-
> lib/sbi/riscv_asm.c | 18 ++++++++----------
> lib/sbi/sbi_hart.c | 28 +++++++++++++++++++++-------
> lib/sbi/sbi_hsm.c | 2 +-
> 5 files changed, 33 insertions(+), 20 deletions(-)
>
> diff --git a/include/sbi/riscv_asm.h b/include/sbi/riscv_asm.h
> index 6e093ca..10f31a7 100644
> --- a/include/sbi/riscv_asm.h
> +++ b/include/sbi/riscv_asm.h
> @@ -180,7 +180,7 @@ int pmp_set(unsigned int n, unsigned long prot, unsigned long addr,
> unsigned long log2len);
>
> int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
> - unsigned long *size);
> + unsigned long *log2len);
>
> #endif /* !__ASSEMBLY__ */
>
> diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h
> index 1e1eb67..0ba68f0 100644
> --- a/include/sbi/sbi_hart.h
> +++ b/include/sbi/sbi_hart.h
> @@ -42,7 +42,8 @@ int sbi_hart_pmp_get(struct sbi_scratch *scratch, unsigned int n,
> unsigned long *prot_out, unsigned long *addr_out,
> unsigned long *size);
> void sbi_hart_pmp_dump(struct sbi_scratch *scratch);
> -int sbi_hart_pmp_check_addr(struct sbi_scratch *scratch, unsigned long daddr,
> +int sbi_hart_pmp_check_addr(struct sbi_scratch *scratch,
> + unsigned long daddr, unsigned long mode,
> unsigned long attr);
> bool sbi_hart_has_feature(struct sbi_scratch *scratch, unsigned long feature);
> void sbi_hart_get_features_str(struct sbi_scratch *scratch,
> diff --git a/lib/sbi/riscv_asm.c b/lib/sbi/riscv_asm.c
> index 799123f..8c54c11 100644
> --- a/lib/sbi/riscv_asm.c
> +++ b/lib/sbi/riscv_asm.c
> @@ -239,16 +239,16 @@ int pmp_set(unsigned int n, unsigned long prot, unsigned long addr,
> }
>
> int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
> - unsigned long *size)
> + unsigned long *log2len)
> {
> int pmpcfg_csr, pmpcfg_shift, pmpaddr_csr;
> unsigned long cfgmask, pmpcfg, prot;
> - unsigned long t1, addr, log2len;
> + unsigned long t1, addr, len;
>
> /* check parameters */
> - if (n >= PMP_COUNT || !prot_out || !addr_out || !size)
> + if (n >= PMP_COUNT || !prot_out || !addr_out || !log2len)
> return SBI_EINVAL;
> - *prot_out = *addr_out = *size = 0;
> + *prot_out = *addr_out = *log2len = 0;
>
> /* calculate PMP register and offset */
> #if __riscv_xlen == 32
> @@ -275,23 +275,21 @@ int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
> addr = csr_read_num(pmpaddr_csr);
> if (addr == -1UL) {
> addr = 0;
> - log2len = __riscv_xlen;
> + len = __riscv_xlen;
> } else {
> t1 = ctz(~addr);
> addr = (addr & ~((1UL << t1) - 1)) << PMP_SHIFT;
> - log2len = (t1 + PMP_SHIFT + 1);
> + len = (t1 + PMP_SHIFT + 1);
> }
> } else {
> addr = csr_read_num(pmpaddr_csr) << PMP_SHIFT;
> - log2len = PMP_SHIFT;
> + len = PMP_SHIFT;
> }
>
> /* return details */
> *prot_out = prot;
> *addr_out = addr;
> -
> - if (log2len < __riscv_xlen)
> - *size = (1UL << log2len);
> + *log2len = len;
>
> return 0;
> }
> diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
> index d788918..4cbe8ce 100644
> --- a/lib/sbi/sbi_hart.c
> +++ b/lib/sbi/sbi_hart.c
> @@ -156,22 +156,31 @@ int sbi_hart_pmp_get(struct sbi_scratch *scratch, unsigned int n,
> unsigned long *prot_out, unsigned long *addr_out,
> unsigned long *size)
> {
> + int err;
> + unsigned long log2size;
> +
> if (sbi_hart_pmp_count(scratch) <= n)
> return SBI_EINVAL;
>
> - return pmp_get(n, prot_out, addr_out, size);
> + err = pmp_get(n, prot_out, addr_out, &log2size);
> + if (err)
> + return err;
> + *size = (log2size < __riscv_xlen) ? 1UL << log2size : 0;
> +
> + return 0;
> }
>
> void sbi_hart_pmp_dump(struct sbi_scratch *scratch)
> {
> - unsigned long prot, addr, size;
> + unsigned long prot, addr, size, log2size;
> unsigned int i, pmp_count;
>
> pmp_count = sbi_hart_pmp_count(scratch);
> for (i = 0; i < pmp_count; i++) {
> - pmp_get(i, &prot, &addr, &size);
> + pmp_get(i, &prot, &addr, &log2size);
> if (!(prot & PMP_A))
> continue;
> + size = (log2size < __riscv_xlen) ? 1UL << log2size : 0;
> #if __riscv_xlen == 32
> sbi_printf("PMP%d : 0x%08lx-0x%08lx (A",
> #else
> @@ -190,18 +199,23 @@ void sbi_hart_pmp_dump(struct sbi_scratch *scratch)
> }
> }
>
> -int sbi_hart_pmp_check_addr(struct sbi_scratch *scratch, unsigned long addr,
> +int sbi_hart_pmp_check_addr(struct sbi_scratch *scratch,
> + unsigned long addr, unsigned long mode,
> unsigned long attr)
> {
> - unsigned long prot, size, tempaddr;
> + unsigned long prot, size, log2size, tempaddr;
> unsigned int i, pmp_count;
>
> pmp_count = sbi_hart_pmp_count(scratch);
> for (i = 0; i < pmp_count; i++) {
> - pmp_get(i, &prot, &tempaddr, &size);
> + pmp_get(i, &prot, &tempaddr, &log2size);
> if (!(prot & PMP_A))
> continue;
> - if (tempaddr <= addr && addr <= tempaddr + size)
> + if (mode == PRV_M && !(prot & PMP_L))
> + continue;
> + size = 1UL << log2size;
> + if ((log2size >= __riscv_xlen) ||
> + ((tempaddr <= addr && addr <= tempaddr + size)))
> if (!(prot & attr))
> return SBI_EINVALID_ADDR;
> }
> diff --git a/lib/sbi/sbi_hsm.c b/lib/sbi/sbi_hsm.c
> index b430793..8c1b7b0 100644
> --- a/lib/sbi/sbi_hsm.c
> +++ b/lib/sbi/sbi_hsm.c
> @@ -231,7 +231,7 @@ int sbi_hsm_hart_start(struct sbi_scratch *scratch, u32 hartid,
> if (hstate != SBI_HART_STOPPED)
> return SBI_EINVAL;
>
> - rc = sbi_hart_pmp_check_addr(scratch, saddr, PMP_X);
> + rc = sbi_hart_pmp_check_addr(scratch, saddr, smode, PMP_X);
> if (rc)
> return rc;
> //TODO: We also need to check saddr for valid physical address as well.
> --
> 2.25.1
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi
LGTM.
Reviewed-by: Atish Patra <atish.patra at wdc.com>
--
Regards,
Atish
More information about the opensbi
mailing list