Commit 5cedae9c authored by Deepak Saxena's avatar Deepak Saxena Committed by Linus Torvalds
Browse files

[PATCH] ARM: Fix XScale PMD setting 

The ARM Architecture Reference Manual lists bit 4 of the PMD as "implementation
defined" and it must be set to zero on Intel XScale CPUs or the cache does
not behave properly. Found by Mike Rapoport while debugging a flash issue
on the PXA255:

	http://marc.10east.com/?l=linux-arm-kernel&m=114845287600782&w=1



Signed-off-by: default avatarDeepak Saxena <dsaxena@plexity.net>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 29f767a2

arch/arm/mm/mm-armv.c

+2 −2
Original line number Diff line number Diff line
@@ -376,7 +376,7 @@ void __init build_mem_type_table(void) 
		ecc_mask = 0;

	}



	if (cpu_arch <= CPU_ARCH_ARMv5TEJ) {

	if (cpu_arch <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) {

		for (i = 0; i < ARRAY_SIZE(mem_types); i++) {

			if (mem_types[i].prot_l1)

				mem_types[i].prot_l1 |= PMD_BIT4;
@@ -631,7 +631,7 @@ void setup_mm_for_reboot(char mode) 
		pgd = init_mm.pgd;



	base_pmdval = PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT;

	if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ)

	if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())

		base_pmdval |= PMD_BIT4;



	for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++, pgd++) {

include/asm-arm/system.h

+6 −0
Original line number Diff line number Diff line
@@ -127,6 +127,12 @@ static inline int cpu_is_xsc3(void) 
}

#endif



#if !defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_CPU_XSC3)

#define	cpu_is_xscale()	0

#else

#define	cpu_is_xscale()	1

#endif



#define set_cr(x)					\

	__asm__ __volatile__(				\

	"mcr	p15, 0, %0, c1, c0, 0	@ set CR"	\

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