diff options
Diffstat (limited to 'arch/mips/mm')
| -rw-r--r-- | arch/mips/mm/sc-rm7k.c | 151 |
1 files changed, 128 insertions, 23 deletions
diff --git a/arch/mips/mm/sc-rm7k.c b/arch/mips/mm/sc-rm7k.c index 53634398a56..1ef75cd80a0 100644 --- a/arch/mips/mm/sc-rm7k.c +++ b/arch/mips/mm/sc-rm7k.c @@ -16,6 +16,7 @@ #include <asm/cacheops.h> #include <asm/mipsregs.h> #include <asm/processor.h> +#include <asm/sections.h> #include <asm/cacheflush.h> /* for run_uncached() */ /* Primary cache parameters. */ @@ -25,11 +26,15 @@ /* Secondary cache parameters. */ #define scache_size (256*1024) /* Fixed to 256KiB on RM7000 */ +/* Tertiary cache parameters */ +#define tc_lsize 32 + extern unsigned long icache_way_size, dcache_way_size; +unsigned long tcache_size; #include <asm/r4kcache.h> -static int rm7k_tcache_enabled; +static int rm7k_tcache_init; /* * Writeback and invalidate the primary cache dcache before DMA. @@ -46,7 +51,7 @@ static void rm7k_sc_wback_inv(unsigned long addr, unsigned long size) blast_scache_range(addr, addr + size); - if (!rm7k_tcache_enabled) + if (!rm7k_tcache_init) return; a = addr & ~(tc_pagesize - 1); @@ -70,7 +75,7 @@ static void rm7k_sc_inv(unsigned long addr, unsigned long size) blast_inv_scache_range(addr, addr + size); - if (!rm7k_tcache_enabled) + if (!rm7k_tcache_init) return; a = addr & ~(tc_pagesize - 1); @@ -83,6 +88,45 @@ static void rm7k_sc_inv(unsigned long addr, unsigned long size) } } +static void blast_rm7k_tcache(void) +{ + unsigned long start = CKSEG0ADDR(0); + unsigned long end = start + tcache_size; + + write_c0_taglo(0); + + while (start < end) { + cache_op(Page_Invalidate_T, start); + start += tc_pagesize; + } +} + +/* + * This function is executed in uncached address space. + */ +static __cpuinit void __rm7k_tc_enable(void) +{ + int i; + + set_c0_config(RM7K_CONF_TE); + + write_c0_taglo(0); + write_c0_taghi(0); + + for (i = 0; i < tcache_size; i += tc_lsize) + cache_op(Index_Store_Tag_T, CKSEG0ADDR(i)); +} + +static __cpuinit void rm7k_tc_enable(void) +{ + if (read_c0_config() & RM7K_CONF_TE) + return; + + BUG_ON(tcache_size == 0); + + run_uncached(__rm7k_tc_enable); +} + /* * This function is executed in uncached address space. */ @@ -104,13 +148,29 @@ static __cpuinit void rm7k_sc_enable(void) if (read_c0_config() & RM7K_CONF_SE) return; - printk(KERN_INFO "Enabling secondary cache...\n"); + pr_info("Enabling secondary cache...\n"); run_uncached(__rm7k_sc_enable); + + if (rm7k_tcache_init) + rm7k_tc_enable(); +} + +static void rm7k_tc_disable(void) +{ + unsigned long flags; + + local_irq_save(flags); + blast_rm7k_tcache(); + clear_c0_config(RM7K_CONF_TE); + local_irq_save(flags); } static void rm7k_sc_disable(void) { clear_c0_config(RM7K_CONF_SE); + + if (rm7k_tcache_init) + rm7k_tc_disable(); } static struct bcache_ops rm7k_sc_ops = { @@ -120,6 +180,52 @@ static struct bcache_ops rm7k_sc_ops = { .bc_inv = rm7k_sc_inv }; +/* + * This is a probing function like the one found in c-r4k.c, we look for the + * wrap around point with different addresses. + */ +static __cpuinit void __probe_tcache(void) +{ + unsigned long flags, addr, begin, end, pow2; + + begin = (unsigned long) &_stext; + begin &= ~((8 * 1024 * 1024) - 1); + end = begin + (8 * 1024 * 1024); + + local_irq_save(flags); + + set_c0_config(RM7K_CONF_TE); + + /* Fill size-multiple lines with a valid tag */ + pow2 = (256 * 1024); + for (addr = begin; addr <= end; addr = (begin + pow2)) { + unsigned long *p = (unsigned long *) addr; + __asm__ __volatile__("nop" : : "r" (*p)); + pow2 <<= 1; + } + + /* Load first line with a 0 tag, to check after */ + write_c0_taglo(0); + write_c0_taghi(0); + cache_op(Index_Store_Tag_T, begin); + + /* Look for the wrap-around */ + pow2 = (512 * 1024); + for (addr = begin + (512 * 1024); addr <= end; addr = begin + pow2) { + cache_op(Index_Load_Tag_T, addr); + if (!read_c0_taglo()) + break; + pow2 <<= 1; + } + + addr -= begin; + tcache_size = addr; + + clear_c0_config(RM7K_CONF_TE); + + local_irq_restore(flags); +} + void __cpuinit rm7k_sc_init(void) { struct cpuinfo_mips *c = ¤t_cpu_data; @@ -139,27 +245,26 @@ void __cpuinit rm7k_sc_init(void) if (!(config & RM7K_CONF_SE)) rm7k_sc_enable(); + bcops = &rm7k_sc_ops; + /* * While we're at it let's deal with the tertiary cache. */ - if (!(config & RM7K_CONF_TC)) { - - /* - * We can't enable the L3 cache yet. There may be board-specific - * magic necessary to turn it on, and blindly asking the CPU to - * start using it would may give cache errors. - * - * Also, board-specific knowledge may allow us to use the - * CACHE Flash_Invalidate_T instruction if the tag RAM supports - * it, and may specify the size of the L3 cache so we don't have - * to probe it. - */ - printk(KERN_INFO "Tertiary cache present, %s enabled\n", - (config & RM7K_CONF_TE) ? "already" : "not (yet)"); - - if ((config & RM7K_CONF_TE)) - rm7k_tcache_enabled = 1; - } - bcops = &rm7k_sc_ops; + rm7k_tcache_init = 0; + tcache_size = 0; + + if (config & RM7K_CONF_TC) + return; + + /* + * No efficient way to ask the hardware for the size of the tcache, + * so must probe for it. + */ + run_uncached(__probe_tcache); + rm7k_tc_enable(); + rm7k_tcache_init = 1; + c->tcache.linesz = tc_lsize; + c->tcache.ways = 1; + pr_info("Tertiary cache size %ldK.\n", (tcache_size >> 10)); } |