Change in coreboot[master]: arch/riscv: Document mprv_{read, write}_* functions

[Jonathan Neuschäfer (Code Review)]

Jonathan Neuschäfer has uploaded this change for review. ( https://review.coreboot.org/21342

Change subject: arch/riscv: Document mprv_{read,write}_* functions
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arch/riscv: Document mprv_{read,write}_* functions

Change-Id: Iaf0cb241f0eb4de241f0983c0b32dbcc28f96480
Signed-off-by: Jonathan Neuschäfer 
---
M src/arch/riscv/include/vm.h
1 file changed, 11 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/42/21342/1

diff --git a/src/arch/riscv/include/vm.h b/src/arch/riscv/include/vm.h
index a65aba9..dadfecd 100644
--- a/src/arch/riscv/include/vm.h
+++ b/src/arch/riscv/include/vm.h
@@ -91,6 +91,17 @@
    	);							\
    }

+/*
+ * mprv_{read,write}_* - Modified privilege memory access functions.
+ *
+ * These inline functions perform a read or write memory operation with the
+ * mstatus.MPRV bit set. This causes the memory protections and translation of
+ * the previous mode (e.g. U-mode, if we're handling a trap from U-mode) to be
+ * applied.
+ *
+ * The user of these functions must make sure to avoid trap loops through
+ * unaligned memory accesses.
+ */
 DEFINE_MPRV_READ(mprv_read_u8, uint8_t, lbu)
 DEFINE_MPRV_READ(mprv_read_u16, uint16_t, lhu)
 DEFINE_MPRV_READ(mprv_read_u32, uint32_t, lwu)