Commit d626f547 authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: Don't fiddle with non-existent caches 



!CONFIG_ARC_HAS_(I|D)CACHE makes Linux disable caches (assuming they
exist in hardware) - mostly for debugging issues with new peripherals.
However, independent of CONFIG_ARC_HAS_(I|D)CACHE, Linux also needs to
handle, non-existant caches, using the information in Cache BCRs (Build
Configuration Reg)

Reported-by: default avatarAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent db8e35d5

arch/arc/mm/cache_arc700.c

+9 −12
Original line number Diff line number Diff line
@@ -144,23 +144,18 @@ void __init read_decode_cache_bcr(void) 
void __init arc_cache_init(void)

{

	unsigned int temp;

#ifdef CONFIG_ARC_CACHE

	unsigned int cpu = smp_processor_id();

#endif

#ifdef CONFIG_ARC_HAS_ICACHE

	struct cpuinfo_arc_cache *ic;

#endif

#ifdef CONFIG_ARC_HAS_DCACHE

	struct cpuinfo_arc_cache *dc;

#endif

	struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;

	struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache;

	int way_pg_ratio = way_pg_ratio;

	char str[256];



	printk(arc_cache_mumbojumbo(0, str, sizeof(str)));



#ifdef CONFIG_ARC_HAS_ICACHE

	ic = &cpuinfo_arc700[cpu].icache;

	if (!ic->ver)

		goto chk_dc;



#ifdef CONFIG_ARC_HAS_ICACHE

	/* 1. Confirm some of I-cache params which Linux assumes */

	if ((ic->assoc != ARC_ICACHE_WAYS) ||

	    (ic->line_len != ARC_ICACHE_LINE_LEN)) {
@@ -213,9 +208,11 @@ void __init arc_cache_init(void) 


	write_aux_reg(ARC_REG_IC_CTRL, temp);



#ifdef CONFIG_ARC_HAS_DCACHE

	dc = &cpuinfo_arc700[cpu].dcache;

chk_dc:

	if (!dc->ver)

		return;



#ifdef CONFIG_ARC_HAS_DCACHE

	if ((dc->assoc != ARC_DCACHE_WAYS) ||

	    (dc->line_len != ARC_DCACHE_LINE_LEN)) {

		panic("Cache H/W doesn't match kernel Config");

CRA Git | Maintained and supported by SUSTech CRA and CCSE