From ce3f7cb96e67d6518c7fc7b361a76409c3817d64 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Tue, 1 Sep 2009 13:32:48 +0900 Subject: [PATCH] sh: Fix dcache flushing for N-way write-through caches. This adopts the special-cased 2-way write-through dcache flusher for N-ways and moves it in to the generic path. Assignment is done at runtime via the check for the CCR_CACHE_WT bit in the same path as the per-way writeback flushers. Signed-off-by: Matt Fleming Signed-off-by: Paul Mundt --- arch/sh/mm/cache-sh4.c | 48 ++++++++++++++++++++++++------------------ 1 file changed, 27 insertions(+), 21 deletions(-) diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c index 397c1030c7a6..b36a9c986a58 100644 --- a/arch/sh/mm/cache-sh4.c +++ b/arch/sh/mm/cache-sh4.c @@ -25,13 +25,14 @@ #define MAX_DCACHE_PAGES 64 /* XXX: Tune for ways */ #define MAX_ICACHE_PAGES 32 +static void __flush_dcache_segment_writethrough(unsigned long start, + unsigned long extent); static void __flush_dcache_segment_1way(unsigned long start, unsigned long extent); static void __flush_dcache_segment_2way(unsigned long start, unsigned long extent); static void __flush_dcache_segment_4way(unsigned long start, unsigned long extent); - static void __flush_cache_4096(unsigned long addr, unsigned long phys, unsigned long exec_offset); @@ -95,10 +96,17 @@ static void __init emit_cache_params(void) */ void __init p3_cache_init(void) { + unsigned int wt_enabled = !!(__raw_readl(CCR) & CCR_CACHE_WT); + compute_alias(&boot_cpu_data.icache); compute_alias(&boot_cpu_data.dcache); compute_alias(&boot_cpu_data.scache); + if (wt_enabled) { + __flush_dcache_segment_fn = __flush_dcache_segment_writethrough; + goto out; + } + switch (boot_cpu_data.dcache.ways) { case 1: __flush_dcache_segment_fn = __flush_dcache_segment_1way; @@ -114,6 +122,7 @@ void __init p3_cache_init(void) break; } +out: emit_cache_params(); } @@ -607,6 +616,23 @@ static void __flush_cache_4096(unsigned long addr, unsigned long phys, * - If caches are disabled or configured in write-through mode, then * the movca.l writes garbage directly into memory. */ +static void __flush_dcache_segment_writethrough(unsigned long start, + unsigned long extent_per_way) +{ + unsigned long addr; + int i; + + addr = CACHE_OC_ADDRESS_ARRAY | (start & cpu_data->dcache.entry_mask); + + while (extent_per_way) { + for (i = 0; i < cpu_data->dcache.ways; i++) + __raw_writel(0, addr + cpu_data->dcache.way_incr * i); + + addr += cpu_data->dcache.linesz; + extent_per_way -= cpu_data->dcache.linesz; + } +} + static void __flush_dcache_segment_1way(unsigned long start, unsigned long extent_per_way) { @@ -655,25 +681,6 @@ static void __flush_dcache_segment_1way(unsigned long start, } while (a0 < a0e); } -#ifdef CONFIG_CACHE_WRITETHROUGH -/* This method of cache flushing avoids the problems discussed - * in the comment above if writethrough caches are enabled. */ -static void __flush_dcache_segment_2way(unsigned long start, - unsigned long extent_per_way) -{ - unsigned long array_addr; - - array_addr = CACHE_OC_ADDRESS_ARRAY | - (start & cpu_data->dcache.entry_mask); - - while (extent_per_way) { - ctrl_outl(0, array_addr); - ctrl_outl(0, array_addr + cpu_data->dcache.way_incr); - array_addr += cpu_data->dcache.linesz; - extent_per_way -= cpu_data->dcache.linesz; - } -} -#else static void __flush_dcache_segment_2way(unsigned long start, unsigned long extent_per_way) { @@ -732,7 +739,6 @@ static void __flush_dcache_segment_2way(unsigned long start, a1 += linesz; } while (a0 < a0e); } -#endif static void __flush_dcache_segment_4way(unsigned long start, unsigned long extent_per_way) -- 2.34.1