dt-bindings: riscv: Add fine-grained IO memory PMP attributes

Introduce new macros to define bitfields for RISC-V Physical Memory
Protection (PMP) attributes, specifically for specifying Read, Write,
and Execute permissions for IO memory regions in device tree bindings.

The following macros are added:
- ATTR_RISCV_TYPE_IO_R: Read access (Bit 8)
- ATTR_RISCV_TYPE_IO_W: Write access (Bit 9)
- ATTR_RISCV_TYPE_IO_X: Execute access (Bit 10)

Corresponding macros for device tree usage are also added:
- DT_MEM_RISCV_TYPE_IO_R
- DT_MEM_RISCV_TYPE_IO_W
- DT_MEM_RISCV_TYPE_IO_X

These macros allow device tree source files to precisely describe the
intended access permissions for memory-mapped IO regions, enhancing
the system's memory protection configuration.

Signed-off-by: Firas Sammoura <[email protected]>

Author: fsammoura1980

include/zephyr/dt-bindings/memory-attr/memory-attr-riscv.h

@@ -24,6 +24,9 @@
 #define  ATTR_RISCV_AMO_ARITHMETIC		BIT(5)
 #define  ATTR_RISCV_IO_IDEMPOTENT_READ		BIT(6)
 #define  ATTR_RISCV_IO_IDEMPOTENT_WRITE		BIT(7)
+#define  ATTR_RISCV_TYPE_IO_R			BIT(8)
+#define  ATTR_RISCV_TYPE_IO_W			BIT(9)
+#define  ATTR_RISCV_TYPE_IO_X			BIT(10)
 
 #define DT_MEM_RISCV_TYPE_MAIN			DT_MEM_RISCV(ATTR_RISCV_TYPE_MAIN)
 #define DT_MEM_RISCV_TYPE_IO			DT_MEM_RISCV(ATTR_RISCV_TYPE_IO)
@@ -33,6 +36,9 @@
 #define DT_MEM_RISCV_AMO_ARITHMETIC		DT_MEM_RISCV(ATTR_RISCV_AMO_ARITHMETIC)
 #define DT_MEM_RISCV_IO_IDEMPOTENT_READ		DT_MEM_RISCV(ATTR_RISCV_IO_IDEMPOTENT_READ)
 #define DT_MEM_RISCV_IO_IDEMPOTENT_WRITE	DT_MEM_RISCV(ATTR_RISCV_IO_IDEMPOTENT_WRITE)
+#define DT_MEM_RISCV_TYPE_IO_R			DT_MEM_RISCV(ATTR_RISCV_TYPE_IO_R)
+#define DT_MEM_RISCV_TYPE_IO_W			DT_MEM_RISCV(ATTR_RISCV_TYPE_IO_W)
+#define DT_MEM_RISCV_TYPE_IO_X			DT_MEM_RISCV(ATTR_RISCV_TYPE_IO_X)
 #define DT_MEM_RISCV_UNKNOWN			DT_MEM_ARCH_ATTR_UNKNOWN
 
 #endif /* ZEPHYR_INCLUDE_DT_BINDINGS_MEM_ATTR_RISCV_H_ */