RISC-V Physical Memory Protection

Implements the physical memory protection extension as specified in
Privileged ISA Version 1.10.

PMP (Physical Memory Protection) is as-of-yet unused and needs testing.
The SiFive verification team have PMP test cases that will be run.

Nothing currently depends on PMP support. It would be preferable to keep
the code in-tree for folk that are interested in RISC-V PMP support.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Daire McNamara <daire.mcnamara@emdalo.com>
Signed-off-by: Ivan Griffin <ivan.griffin@emdalo.com>
Signed-off-by: Michael Clark <mjc@sifive.com>

1 files changed, 64 insertions, 0 deletions

diff --git a/target/riscv/pmp.h b/target/riscv/pmp.h
new file mode 100644
index 0000000000..e3953c885f
--- /dev/null
+++ b/target/riscv/pmp.h
@@ -0,0 +1,64 @@
+/*
+ * QEMU RISC-V PMP (Physical Memory Protection)
+ *
+ * Author: Daire McNamara, daire.mcnamara@emdalo.com
+ *         Ivan Griffin, ivan.griffin@emdalo.com
+ *
+ * This provides a RISC-V Physical Memory Protection interface
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _RISCV_PMP_H_
+#define _RISCV_PMP_H_
+
+typedef enum {
+    PMP_READ  = 1 << 0,
+    PMP_WRITE = 1 << 1,
+    PMP_EXEC  = 1 << 2,
+    PMP_LOCK  = 1 << 7
+} pmp_priv_t;
+
+typedef enum {
+    PMP_AMATCH_OFF,  /* Null (off)                            */
+    PMP_AMATCH_TOR,  /* Top of Range                          */
+    PMP_AMATCH_NA4,  /* Naturally aligned four-byte region    */
+    PMP_AMATCH_NAPOT /* Naturally aligned power-of-two region */
+} pmp_am_t;
+
+typedef struct {
+    target_ulong addr_reg;
+    uint8_t  cfg_reg;
+} pmp_entry_t;
+
+typedef struct {
+    target_ulong sa;
+    target_ulong ea;
+} pmp_addr_t;
+
+typedef struct {
+    pmp_entry_t pmp[MAX_RISCV_PMPS];
+    pmp_addr_t  addr[MAX_RISCV_PMPS];
+    uint32_t num_rules;
+} pmp_table_t;
+
+void pmpcfg_csr_write(CPURISCVState *env, uint32_t reg_index,
+    target_ulong val);
+target_ulong pmpcfg_csr_read(CPURISCVState *env, uint32_t reg_index);
+void pmpaddr_csr_write(CPURISCVState *env, uint32_t addr_index,
+    target_ulong val);
+target_ulong pmpaddr_csr_read(CPURISCVState *env, uint32_t addr_index);
+bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr,
+    target_ulong size, pmp_priv_t priv);
+
+#endif