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ARM: 9356/2: Move asm statements accessing TTBCR into C functions

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This patch implements cpu_get_ttbcr() and cpu_set_ttbcr() and replaces
the corresponding asm statements.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
This commit is contained in:
Linus Walleij 2024-03-25 08:28:50 +01:00 committed by Russell King (Oracle)
parent a8f15b31a6
commit 66abdd3b5d
2 changed files with 15 additions and 4 deletions
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12
arch/arm/include/asm/proc-fns.h
View file

@ -178,6 +178,18 @@ extern void cpu_resume(void);
})
#endif
static inline unsigned int cpu_get_ttbcr(void)
{
unsigned int ttbcr;
asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
return ttbcr;
}
static inline void cpu_set_ttbcr(unsigned int ttbcr)
{
asm("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr));
}
#else /*!CONFIG_MMU */
#define cpu_switch_mm(pgd,mm) { }

7
arch/arm/mm/mmu.c
View file

@ -1687,9 +1687,8 @@ static void __init early_paging_init(const struct machine_desc *mdesc)
*/
cr = get_cr();
set_cr(cr & ~(CR_I | CR_C));
asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
asm volatile("mcr p15, 0, %0, c2, c0, 2"
: : "r" (ttbcr & ~(3 << 8 | 3 << 10)));
ttbcr = cpu_get_ttbcr();
cpu_set_ttbcr(ttbcr & ~(3 << 8 | 3 << 10));
flush_cache_all();
/*
@ -1701,7 +1700,7 @@ static void __init early_paging_init(const struct machine_desc *mdesc)
lpae_pgtables_remap(offset, pa_pgd);
/* Re-enable the caches and cacheable TLB walks */
asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr));
cpu_set_ttbcr(ttbcr);
set_cr(cr);
}