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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-05 01:22:07 +0300 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-10 12:52:41 +0300 |
| commit | 6c5c2a01fcfdb70f2e95e30e96ccf53b88e81023 (patch) | |
| tree | 43270eb85618290754b284806a66ff1bbb6d0223 /arch/arm/mm/proc-macros.S | |
| parent | f6ac49ba29499387e12e864a22e6d4bf46dafe9b (diff) | |
| download | linux-6c5c2a01fcfdb70f2e95e30e96ccf53b88e81023.tar.xz | |
ARM: proc-arm94*.S: fix setup function
Both ARM946 and ARM940 setup functions were corrupting r1 and r2,
which is not permissible - these are used to carry the machine ID
and boot data into the kernel, and must be preserved.
The code responsible for this was the same in both files: they were
using the registers to generate a protection region register value.
Fix this by turning this process into a macro, and using that macro
in both these files with an alternative register allocation. r0,
r3 and r7 can be used for temporary values here.
Reported-by: Alex Dumitrache <broscutamaker@gmail.com>
Tested-by: Georg Hofstetter <g3gg0.de@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/proc-macros.S')
| -rw-r--r-- | arch/arm/mm/proc-macros.S | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S index 082b9f2f7e90..d081c9d9420d 100644 --- a/arch/arm/mm/proc-macros.S +++ b/arch/arm/mm/proc-macros.S @@ -331,3 +331,27 @@ ENTRY(\name\()_tlb_fns) .globl \x .equ \x, \y .endm + + /* + * Macro to calculate the log2 size for the protection region + * registers. This calculates rd = log2(size) - 1. tmp must + * not be the same register as rd. + */ +.macro pr_sz, rd, size, tmp + mov \tmp, \size, lsr #12 + mov \rd, #11 +1: movs \tmp, \tmp, lsr #1 + addne \rd, \rd, #1 + bne 1b +.endm + + /* + * Macro to generate a protection region register value + * given a pre-masked address, size, and enable bit. + * Corrupts size. + */ +.macro pr_val, dest, addr, size, enable + pr_sz \dest, \size, \size @ calculate log2(size) - 1 + orr \dest, \addr, \dest, lsl #1 @ mask in the region size + orr \dest, \dest, \enable +.endm |