lib: sbi: Improve PMP CSR detection and progamming

As-per latest RISC-V privilege spec up to 64 PMP entries are supported.
Implementations may implement zero, 16, or 64 PMP CSRs. All PMP CSR
fields are WARL and may be hardwired to zero.

This patch improves PMP CSR detection and progamming considering
above facts.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

diff --git a/include/sbi/riscv_encoding.h b/include/sbi/riscv_encoding.h
index 827c86c..073261f 100644 (file)
--- a/include/sbi/riscv_encoding.h
+++ b/include/sbi/riscv_encoding.h
@@ -144,7 +144,12 @@
 #define PMP_L                          _UL(0x80)
 
 #define PMP_SHIFT                      2
-#define PMP_COUNT                      16
+#define PMP_COUNT                      64
+#if __riscv_xlen == 64
+#define PMP_ADDR_MASK                  ((_ULL(0x1) << 54) - 1)
+#else
+#define PMP_ADDR_MASK                  _UL(0xFFFFFFFF)
+#endif
 
 #if __riscv_xlen == 64
 #define MSTATUS_SD                     MSTATUS64_SD
@@ -263,6 +268,18 @@
 #define CSR_PMPCFG1                    0x3a1
 #define CSR_PMPCFG2                    0x3a2
 #define CSR_PMPCFG3                    0x3a3
+#define CSR_PMPCFG4                    0x3a4
+#define CSR_PMPCFG5                    0x3a5
+#define CSR_PMPCFG6                    0x3a6
+#define CSR_PMPCFG7                    0x3a7
+#define CSR_PMPCFG8                    0x3a8
+#define CSR_PMPCFG9                    0x3a9
+#define CSR_PMPCFG10                   0x3aa
+#define CSR_PMPCFG11                   0x3ab
+#define CSR_PMPCFG12                   0x3ac
+#define CSR_PMPCFG13                   0x3ad
+#define CSR_PMPCFG14                   0x3ae
+#define CSR_PMPCFG15                   0x3af
 #define CSR_PMPADDR0                   0x3b0
 #define CSR_PMPADDR1                   0x3b1
 #define CSR_PMPADDR2                   0x3b2
@@ -279,6 +296,54 @@
 #define CSR_PMPADDR13                  0x3bd
 #define CSR_PMPADDR14                  0x3be
 #define CSR_PMPADDR15                  0x3bf
+#define CSR_PMPADDR16                  0x3c0
+#define CSR_PMPADDR17                  0x3c1
+#define CSR_PMPADDR18                  0x3c2
+#define CSR_PMPADDR19                  0x3c3
+#define CSR_PMPADDR20                  0x3c4
+#define CSR_PMPADDR21                  0x3c5
+#define CSR_PMPADDR22                  0x3c6
+#define CSR_PMPADDR23                  0x3c7
+#define CSR_PMPADDR24                  0x3c8
+#define CSR_PMPADDR25                  0x3c9
+#define CSR_PMPADDR26                  0x3ca
+#define CSR_PMPADDR27                  0x3cb
+#define CSR_PMPADDR28                  0x3cc
+#define CSR_PMPADDR29                  0x3cd
+#define CSR_PMPADDR30                  0x3ce
+#define CSR_PMPADDR31                  0x3cf
+#define CSR_PMPADDR32                  0x3d0
+#define CSR_PMPADDR33                  0x3d1
+#define CSR_PMPADDR34                  0x3d2
+#define CSR_PMPADDR35                  0x3d3
+#define CSR_PMPADDR36                  0x3d4
+#define CSR_PMPADDR37                  0x3d5
+#define CSR_PMPADDR38                  0x3d6
+#define CSR_PMPADDR39                  0x3d7
+#define CSR_PMPADDR40                  0x3d8
+#define CSR_PMPADDR41                  0x3d9
+#define CSR_PMPADDR42                  0x3da
+#define CSR_PMPADDR43                  0x3db
+#define CSR_PMPADDR44                  0x3dc
+#define CSR_PMPADDR45                  0x3dd
+#define CSR_PMPADDR46                  0x3de
+#define CSR_PMPADDR47                  0x3df
+#define CSR_PMPADDR48                  0x3e0
+#define CSR_PMPADDR49                  0x3e1
+#define CSR_PMPADDR50                  0x3e2
+#define CSR_PMPADDR51                  0x3e3
+#define CSR_PMPADDR52                  0x3e4
+#define CSR_PMPADDR53                  0x3e5
+#define CSR_PMPADDR54                  0x3e6
+#define CSR_PMPADDR55                  0x3e7
+#define CSR_PMPADDR56                  0x3e8
+#define CSR_PMPADDR57                  0x3e9
+#define CSR_PMPADDR58                  0x3ea
+#define CSR_PMPADDR59                  0x3eb
+#define CSR_PMPADDR60                  0x3ec
+#define CSR_PMPADDR61                  0x3ed
+#define CSR_PMPADDR62                  0x3ee
+#define CSR_PMPADDR63                  0x3ef
 #define CSR_TSELECT                    0x7a0
 #define CSR_TDATA1                     0x7a1
 #define CSR_TDATA2                     0x7a2

diff --git a/lib/sbi/riscv_asm.c b/lib/sbi/riscv_asm.c
index 6dfebd9..799123f 100644 (file)
--- a/lib/sbi/riscv_asm.c
+++ b/lib/sbi/riscv_asm.c
@@ -90,142 +90,88 @@ void misa_string(int xlen, char *out, unsigned int out_sz)
 
 unsigned long csr_read_num(int csr_num)
 {
+#define switchcase_csr_read(__csr_num, __val)          \
+       case __csr_num:                                 \
+               __val = csr_read(__csr_num);            \
+               break;
+#define switchcase_csr_read_2(__csr_num, __val)        \
+       switchcase_csr_read(__csr_num + 0, __val)       \
+       switchcase_csr_read(__csr_num + 1, __val)
+#define switchcase_csr_read_4(__csr_num, __val)        \
+       switchcase_csr_read_2(__csr_num + 0, __val)     \
+       switchcase_csr_read_2(__csr_num + 2, __val)
+#define switchcase_csr_read_8(__csr_num, __val)        \
+       switchcase_csr_read_4(__csr_num + 0, __val)     \
+       switchcase_csr_read_4(__csr_num + 4, __val)
+#define switchcase_csr_read_16(__csr_num, __val)       \
+       switchcase_csr_read_8(__csr_num + 0, __val)     \
+       switchcase_csr_read_8(__csr_num + 8, __val)
+#define switchcase_csr_read_32(__csr_num, __val)       \
+       switchcase_csr_read_16(__csr_num + 0, __val)    \
+       switchcase_csr_read_16(__csr_num + 16, __val)
+#define switchcase_csr_read_64(__csr_num, __val)       \
+       switchcase_csr_read_32(__csr_num + 0, __val)    \
+       switchcase_csr_read_32(__csr_num + 32, __val)
+
        unsigned long ret = 0;
 
        switch (csr_num) {
-       case CSR_PMPCFG0:
-               ret = csr_read(CSR_PMPCFG0);
-               break;
-       case CSR_PMPCFG1:
-               ret = csr_read(CSR_PMPCFG1);
-               break;
-       case CSR_PMPCFG2:
-               ret = csr_read(CSR_PMPCFG2);
-               break;
-       case CSR_PMPCFG3:
-               ret = csr_read(CSR_PMPCFG3);
-               break;
-       case CSR_PMPADDR0:
-               ret = csr_read(CSR_PMPADDR0);
-               break;
-       case CSR_PMPADDR1:
-               ret = csr_read(CSR_PMPADDR1);
-               break;
-       case CSR_PMPADDR2:
-               ret = csr_read(CSR_PMPADDR2);
-               break;
-       case CSR_PMPADDR3:
-               ret = csr_read(CSR_PMPADDR3);
-               break;
-       case CSR_PMPADDR4:
-               ret = csr_read(CSR_PMPADDR4);
-               break;
-       case CSR_PMPADDR5:
-               ret = csr_read(CSR_PMPADDR5);
-               break;
-       case CSR_PMPADDR6:
-               ret = csr_read(CSR_PMPADDR6);
-               break;
-       case CSR_PMPADDR7:
-               ret = csr_read(CSR_PMPADDR7);
-               break;
-       case CSR_PMPADDR8:
-               ret = csr_read(CSR_PMPADDR8);
-               break;
-       case CSR_PMPADDR9:
-               ret = csr_read(CSR_PMPADDR9);
-               break;
-       case CSR_PMPADDR10:
-               ret = csr_read(CSR_PMPADDR10);
-               break;
-       case CSR_PMPADDR11:
-               ret = csr_read(CSR_PMPADDR11);
-               break;
-       case CSR_PMPADDR12:
-               ret = csr_read(CSR_PMPADDR12);
-               break;
-       case CSR_PMPADDR13:
-               ret = csr_read(CSR_PMPADDR13);
-               break;
-       case CSR_PMPADDR14:
-               ret = csr_read(CSR_PMPADDR14);
-               break;
-       case CSR_PMPADDR15:
-               ret = csr_read(CSR_PMPADDR15);
-               break;
+       switchcase_csr_read_16(CSR_PMPCFG0, ret)
+       switchcase_csr_read_64(CSR_PMPADDR0, ret)
        default:
                break;
        };
 
        return ret;
+
+#undef switchcase_csr_read_64
+#undef switchcase_csr_read_32
+#undef switchcase_csr_read_16
+#undef switchcase_csr_read_8
+#undef switchcase_csr_read_4
+#undef switchcase_csr_read_2
+#undef switchcase_csr_read
 }
 
 void csr_write_num(int csr_num, unsigned long val)
 {
+#define switchcase_csr_write(__csr_num, __val)         \
+       case __csr_num:                                 \
+               csr_write(__csr_num, __val);            \
+               break;
+#define switchcase_csr_write_2(__csr_num, __val)       \
+       switchcase_csr_write(__csr_num + 0, __val)      \
+       switchcase_csr_write(__csr_num + 1, __val)
+#define switchcase_csr_write_4(__csr_num, __val)       \
+       switchcase_csr_write_2(__csr_num + 0, __val)    \
+       switchcase_csr_write_2(__csr_num + 2, __val)
+#define switchcase_csr_write_8(__csr_num, __val)       \
+       switchcase_csr_write_4(__csr_num + 0, __val)    \
+       switchcase_csr_write_4(__csr_num + 4, __val)
+#define switchcase_csr_write_16(__csr_num, __val)      \
+       switchcase_csr_write_8(__csr_num + 0, __val)    \
+       switchcase_csr_write_8(__csr_num + 8, __val)
+#define switchcase_csr_write_32(__csr_num, __val)      \
+       switchcase_csr_write_16(__csr_num + 0, __val)   \
+       switchcase_csr_write_16(__csr_num + 16, __val)
+#define switchcase_csr_write_64(__csr_num, __val)      \
+       switchcase_csr_write_32(__csr_num + 0, __val)   \
+       switchcase_csr_write_32(__csr_num + 32, __val)
+
        switch (csr_num) {
-       case CSR_PMPCFG0:
-               csr_write(CSR_PMPCFG0, val);
-               break;
-       case CSR_PMPCFG1:
-               csr_write(CSR_PMPCFG1, val);
-               break;
-       case CSR_PMPCFG2:
-               csr_write(CSR_PMPCFG2, val);
-               break;
-       case CSR_PMPCFG3:
-               csr_write(CSR_PMPCFG3, val);
-               break;
-       case CSR_PMPADDR0:
-               csr_write(CSR_PMPADDR0, val);
-               break;
-       case CSR_PMPADDR1:
-               csr_write(CSR_PMPADDR1, val);
-               break;
-       case CSR_PMPADDR2:
-               csr_write(CSR_PMPADDR2, val);
-               break;
-       case CSR_PMPADDR3:
-               csr_write(CSR_PMPADDR3, val);
-               break;
-       case CSR_PMPADDR4:
-               csr_write(CSR_PMPADDR4, val);
-               break;
-       case CSR_PMPADDR5:
-               csr_write(CSR_PMPADDR5, val);
-               break;
-       case CSR_PMPADDR6:
-               csr_write(CSR_PMPADDR6, val);
-               break;
-       case CSR_PMPADDR7:
-               csr_write(CSR_PMPADDR7, val);
-               break;
-       case CSR_PMPADDR8:
-               csr_write(CSR_PMPADDR8, val);
-               break;
-       case CSR_PMPADDR9:
-               csr_write(CSR_PMPADDR9, val);
-               break;
-       case CSR_PMPADDR10:
-               csr_write(CSR_PMPADDR10, val);
-               break;
-       case CSR_PMPADDR11:
-               csr_write(CSR_PMPADDR11, val);
-               break;
-       case CSR_PMPADDR12:
-               csr_write(CSR_PMPADDR12, val);
-               break;
-       case CSR_PMPADDR13:
-               csr_write(CSR_PMPADDR13, val);
-               break;
-       case CSR_PMPADDR14:
-               csr_write(CSR_PMPADDR14, val);
-               break;
-       case CSR_PMPADDR15:
-               csr_write(CSR_PMPADDR15, val);
-               break;
+       switchcase_csr_write_16(CSR_PMPCFG0, val)
+       switchcase_csr_write_64(CSR_PMPADDR0, val)
        default:
                break;
        };
+
+#undef switchcase_csr_write_64
+#undef switchcase_csr_write_32
+#undef switchcase_csr_write_16
+#undef switchcase_csr_write_8
+#undef switchcase_csr_write_4
+#undef switchcase_csr_write_2
+#undef switchcase_csr_write
 }
 
 static unsigned long ctz(unsigned long x)

diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index 80ed86a..8f31d58 100644 (file)
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -340,31 +340,55 @@ static void hart_detect_features(struct sbi_scratch *scratch)
        hfeatures->features = 0;
        hfeatures->pmp_count = 0;
 
-       /* Detect if hart supports PMP feature */
-#define __detect_pmp(__pmp_csr)                                        \
-       val = csr_read_allowed(__pmp_csr, (ulong)&trap);        \
-       if (!trap.cause) {                                      \
-               csr_write_allowed(__pmp_csr, (ulong)&trap, val);\
-               if (!trap.cause)                                \
-                       hfeatures->pmp_count++;                 \
+#define __check_csr(__csr, __rdonly, __wrval, __field, __skip) \
+       val = csr_read_allowed(__csr, (ulong)&trap);                    \
+       if (!trap.cause) {                                              \
+               if (__rdonly) {                                         \
+                       (hfeatures->__field)++;                         \
+               } else {                                                \
+                       csr_write_allowed(__csr, (ulong)&trap, __wrval);\
+                       if (!trap.cause) {                              \
+                               if (csr_swap(__csr, val) == __wrval)    \
+                                       (hfeatures->__field)++;         \
+                               else                                    \
+                                       goto __skip;                    \
+                       } else {                                        \
+                               goto __skip;                            \
+                       }                                               \
+               }                                                       \
+       } else {                                                        \
+               goto __skip;                                            \
        }
-       __detect_pmp(CSR_PMPADDR0);
-       __detect_pmp(CSR_PMPADDR1);
-       __detect_pmp(CSR_PMPADDR2);
-       __detect_pmp(CSR_PMPADDR3);
-       __detect_pmp(CSR_PMPADDR4);
-       __detect_pmp(CSR_PMPADDR5);
-       __detect_pmp(CSR_PMPADDR6);
-       __detect_pmp(CSR_PMPADDR7);
-       __detect_pmp(CSR_PMPADDR8);
-       __detect_pmp(CSR_PMPADDR9);
-       __detect_pmp(CSR_PMPADDR10);
-       __detect_pmp(CSR_PMPADDR11);
-       __detect_pmp(CSR_PMPADDR12);
-       __detect_pmp(CSR_PMPADDR13);
-       __detect_pmp(CSR_PMPADDR14);
-       __detect_pmp(CSR_PMPADDR15);
-#undef __detect_pmp
+#define __check_csr_2(__csr, __rdonly, __wrval, __field, __skip)       \
+       __check_csr(__csr + 0, __rdonly, __wrval, __field, __skip)      \
+       __check_csr(__csr + 1, __rdonly, __wrval, __field, __skip)
+#define __check_csr_4(__csr, __rdonly, __wrval, __field, __skip)       \
+       __check_csr_2(__csr + 0, __rdonly, __wrval, __field, __skip)    \
+       __check_csr_2(__csr + 2, __rdonly, __wrval, __field, __skip)
+#define __check_csr_8(__csr, __rdonly, __wrval, __field, __skip)       \
+       __check_csr_4(__csr + 0, __rdonly, __wrval, __field, __skip)    \
+       __check_csr_4(__csr + 4, __rdonly, __wrval, __field, __skip)
+#define __check_csr_16(__csr, __rdonly, __wrval, __field, __skip)      \
+       __check_csr_8(__csr + 0, __rdonly, __wrval, __field, __skip)    \
+       __check_csr_8(__csr + 8, __rdonly, __wrval, __field, __skip)
+#define __check_csr_32(__csr, __rdonly, __wrval, __field, __skip)      \
+       __check_csr_16(__csr + 0, __rdonly, __wrval, __field, __skip)   \
+       __check_csr_16(__csr + 16, __rdonly, __wrval, __field, __skip)
+#define __check_csr_64(__csr, __rdonly, __wrval, __field, __skip)      \
+       __check_csr_32(__csr + 0, __rdonly, __wrval, __field, __skip)   \
+       __check_csr_32(__csr + 32, __rdonly, __wrval, __field, __skip)
+
+       /* Detect number of PMP regions */
+       __check_csr_64(CSR_PMPADDR0, 0, PMP_ADDR_MASK, pmp_count, __pmp_skip);
+__pmp_skip:
+
+#undef __check_csr_64
+#undef __check_csr_32
+#undef __check_csr_16
+#undef __check_csr_8
+#undef __check_csr_4
+#undef __check_csr_2
+#undef __check_csr
 
        /* Detect if hart supports SCOUNTEREN feature */
        trap.cause = 0;