From f12d0d7c7786af39435ef6ae9defe47fb58f6091 Mon Sep 17 00:00:00 2001 From: "Hyok S. Choi" Date: Tue, 26 Sep 2006 17:36:37 +0900 Subject: [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 Signed-off-by: Russell King --- arch/arm/kernel/head-nommu.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel/head-nommu.S') diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index ac9eb3d3051..698a537915d 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 @@ -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 -- cgit v1.2.3