lib: sbi: Introduce pmp_t type

To help abstract details of PMP encoding and access, add a new pmp_t
type which contains address and cfg in the format of the riscv CSRs.
There is no functional change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260430045528.420437-2-npiggin@gmail.com
Signed-off-by: Anup Patel <anup@brainfault.org>
This commit is contained in:
Nicholas Piggin
2026-04-30 14:55:18 +10:00
committed by Anup Patel
parent 73bc794b40
commit 8ae3b0985a
+26 -15
View File
@@ -272,6 +272,12 @@ void csr_write_num(int csr_num, unsigned long val)
#undef switchcase_csr_write
}
struct pmp {
unsigned long addr;
u8 cfg;
};
typedef struct pmp pmp_t;
static unsigned long ctz(unsigned long x)
{
unsigned long ret = 0;
@@ -335,7 +341,8 @@ int pmp_set(unsigned int n, unsigned long prot, unsigned long addr,
{
int pmpcfg_csr, pmpcfg_shift, pmpaddr_csr;
unsigned long cfgmask, pmpcfg;
unsigned long addrmask, pmpaddr;
unsigned long addrmask;
pmp_t pmp;
/* check parameters */
if (n >= PMP_COUNT || log2len > __riscv_xlen || log2len < PMP_SHIFT)
@@ -356,25 +363,26 @@ int pmp_set(unsigned int n, unsigned long prot, unsigned long addr,
/* encode PMP config */
prot &= ~PMP_A;
prot |= (log2len == PMP_SHIFT) ? PMP_A_NA4 : PMP_A_NAPOT;
cfgmask = ~(0xffUL << pmpcfg_shift);
pmpcfg = (csr_read_num(pmpcfg_csr) & cfgmask);
pmpcfg |= ((prot << pmpcfg_shift) & ~cfgmask);
pmp.cfg = prot;
/* encode PMP address */
if (log2len == PMP_SHIFT) {
pmpaddr = (addr >> PMP_SHIFT);
pmp.addr = (addr >> PMP_SHIFT);
} else {
if (log2len == __riscv_xlen) {
pmpaddr = -1UL;
pmp.addr = -1UL;
} else {
addrmask = (1UL << (log2len - PMP_SHIFT)) - 1;
pmpaddr = ((addr >> PMP_SHIFT) & ~addrmask);
pmpaddr |= (addrmask >> 1);
pmp.addr = ((addr >> PMP_SHIFT) & ~addrmask);
pmp.addr |= (addrmask >> 1);
}
}
/* write csrs */
csr_write_num(pmpaddr_csr, pmpaddr);
csr_write_num(pmpaddr_csr, pmp.addr);
cfgmask = ~(0xffUL << pmpcfg_shift);
pmpcfg = (csr_read_num(pmpcfg_csr) & cfgmask);
pmpcfg |= (((unsigned long)pmp.cfg << pmpcfg_shift) & ~cfgmask);
csr_write_num(pmpcfg_csr, pmpcfg);
return 0;
@@ -384,8 +392,9 @@ int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
unsigned long *log2len)
{
int pmpcfg_csr, pmpcfg_shift, pmpaddr_csr;
unsigned long cfgmask, pmpcfg, prot;
unsigned long cfgmask, prot;
unsigned long t1, addr, len;
pmp_t pmp;
/* check parameters */
if (n >= PMP_COUNT || !prot_out || !addr_out || !log2len)
@@ -404,14 +413,16 @@ int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
#endif
pmpaddr_csr = CSR_PMPADDR0 + n;
/* decode PMP config */
cfgmask = (0xffUL << pmpcfg_shift);
pmpcfg = csr_read_num(pmpcfg_csr) & cfgmask;
prot = pmpcfg >> pmpcfg_shift;
pmp.cfg = (csr_read_num(pmpcfg_csr) & cfgmask) >> pmpcfg_shift;
pmp.addr = csr_read_num(pmpaddr_csr);
/* decode PMP config */
prot = pmp.cfg;
/* decode PMP address */
if ((prot & PMP_A) == PMP_A_NAPOT) {
addr = csr_read_num(pmpaddr_csr);
addr = pmp.addr;
if (addr == -1UL) {
addr = 0;
len = __riscv_xlen;
@@ -421,7 +432,7 @@ int pmp_get(unsigned int n, unsigned long *prot_out, unsigned long *addr_out,
len = (t1 + PMP_SHIFT + 1);
}
} else {
addr = csr_read_num(pmpaddr_csr) << PMP_SHIFT;
addr = pmp.addr << PMP_SHIFT;
len = PMP_SHIFT;
}