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author | Jonathan Neuschäfer <j.neuschaefer@gmx.net> | 2017-09-18 21:20:38 +0200 |
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committer | Martin Roth <martinroth@google.com> | 2017-09-27 16:39:49 +0000 |
commit | 69a143d682919bb27beb317616ef8d0eecf67dd4 (patch) | |
tree | cc235bfb72cf23d50c576b55594c36d3f839f41b | |
parent | d54c1cc770147039116e945b559928cc8467090e (diff) | |
download | coreboot-69a143d682919bb27beb317616ef8d0eecf67dd4.tar.xz |
arch/riscv: Document mprv_{read,write}_* functions
Change-Id: Iaf0cb241f0eb4de241f0983c0b32dbcc28f96480
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/21342
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
-rw-r--r-- | src/arch/riscv/include/vm.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/src/arch/riscv/include/vm.h b/src/arch/riscv/include/vm.h index a65aba9db8..dadfecd8b4 100644 --- a/src/arch/riscv/include/vm.h +++ b/src/arch/riscv/include/vm.h @@ -91,6 +91,17 @@ void flush_tlb(void); ); \ } +/* + * 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) |