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| author | Hyok S. Choi <hyok.choi@samsung.com> | 2006-09-26 17:36:37 +0900 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2006-09-27 17:34:30 +0100 |
| commit | f12d0d7c7786af39435ef6ae9defe47fb58f6091 (patch) | |
| tree | 03361f2b925754f2acf4f311df2122f844d3d4fe /arch/arm/kernel/head-nommu.S | |
| parent | fefdaa06ccdde394be865ed76509be82813e425b (diff) | |
| download | lwn-f12d0d7c7786af39435ef6ae9defe47fb58f6091.tar.gz lwn-f12d0d7c7786af39435ef6ae9defe47fb58f6091.zip | |
[ARM] nommu: manage the CP15 things
All the current CP15 access codes in ARM arch can be categorized and
conditioned by the defines as follows:
Related operation Safe condition
a. any CP15 access !CPU_CP15
b. alignment trap CPU_CP15_MMU
c. D-cache(C-bit) CPU_CP15
d. I-cache CPU_CP15 && !( CPU_ARM610 || CPU_ARM710 ||
CPU_ARM720 || CPU_ARM740 ||
CPU_XSCALE || CPU_XSC3 )
e. alternate vector CPU_CP15 && !CPU_ARM740
f. TTB CPU_CP15_MMU
g. Domain CPU_CP15_MMU
h. FSR/FAR CPU_CP15_MMU
For example, alternate vector is supported if and only if
"CPU_CP15 && !CPU_ARM740" is satisfied.
Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/head-nommu.S')
| -rw-r--r-- | arch/arm/kernel/head-nommu.S | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index ac9eb3d30518..698a537915dd 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -9,7 +9,6 @@ * published by the Free Software Foundation. * * Common kernel startup code (non-paged MM) - * for 32-bit CPUs which has a process ID register(CP15). * */ #include <linux/linkage.h> @@ -40,7 +39,11 @@ ENTRY(stext) msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | SVC_MODE @ ensure svc mode @ and irqs disabled +#ifndef CONFIG_CPU_CP15 + ldr r9, =CONFIG_PROCESSOR_ID +#else mrc p15, 0, r9, c0, c0 @ get processor id +#endif bl __lookup_processor_type @ r5=procinfo r9=cpuid movs r10, r5 @ invalid processor (r5=0)? beq __error_p @ yes, error 'p' @@ -58,6 +61,7 @@ ENTRY(stext) */ .type __after_proc_init, %function __after_proc_init: +#ifdef CONFIG_CPU_CP15 mrc p15, 0, r0, c1, c0, 0 @ read control reg #ifdef CONFIG_ALIGNMENT_TRAP orr r0, r0, #CR_A @@ -74,6 +78,7 @@ __after_proc_init: bic r0, r0, #CR_I #endif mcr p15, 0, r0, c1, c0, 0 @ write control reg +#endif /* CONFIG_CPU_CP15 */ mov pc, r13 @ clear the BSS and jump @ to start_kernel |