From c1537b4863da620f12f5b42ece61bf65314148ed Mon Sep 17 00:00:00 2001 From: Phil Edworthy Date: Mon, 9 Jan 2012 16:08:47 +0000 Subject: [PATCH] sh: sh2a: Improve cache flush/invalidate functions The cache functions lock out interrupts for long periods; this patch reduces the impact when operating on large address ranges. In such cases it will: - Invalidate the entire cache rather than individual addresses. - Do nothing when flushing the operand cache in write-through mode. - When flushing the operand cache in write-back mdoe, index the search for matching addresses on the cache entires instead of the addresses to flush Note: sh2a__flush_purge_region was only invalidating the operand cache, this adds flush. Signed-off-by: Phil Edworthy Signed-off-by: Paul Mundt --- arch/sh/mm/cache-sh2a.c | 123 +++++++++++++++++++++++++++------------- 1 file changed, 84 insertions(+), 39 deletions(-) diff --git a/arch/sh/mm/cache-sh2a.c b/arch/sh/mm/cache-sh2a.c index 1f51225426a..ae08cbbfa56 100644 --- a/arch/sh/mm/cache-sh2a.c +++ b/arch/sh/mm/cache-sh2a.c @@ -15,35 +15,78 @@ #include #include +/* + * The maximum number of pages we support up to when doing ranged dcache + * flushing. Anything exceeding this will simply flush the dcache in its + * entirety. + */ +#define MAX_OCACHE_PAGES 32 +#define MAX_ICACHE_PAGES 32 + +static void sh2a_flush_oc_line(unsigned long v, int way) +{ + unsigned long addr = (v & 0x000007f0) | (way << 11); + unsigned long data; + + data = __raw_readl(CACHE_OC_ADDRESS_ARRAY | addr); + if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) { + data &= ~SH_CACHE_UPDATED; + __raw_writel(data, CACHE_OC_ADDRESS_ARRAY | addr); + } +} + +static void sh2a_invalidate_line(unsigned long cache_addr, unsigned long v) +{ + /* Set associative bit to hit all ways */ + unsigned long addr = (v & 0x000007f0) | SH_CACHE_ASSOC; + __raw_writel((addr & CACHE_PHYSADDR_MASK), cache_addr | addr); +} + +/* + * Write back the dirty D-caches, but not invalidate them. + */ static void sh2a__flush_wback_region(void *start, int size) { +#ifdef CONFIG_CACHE_WRITEBACK unsigned long v; unsigned long begin, end; unsigned long flags; + int nr_ways; begin = (unsigned long)start & ~(L1_CACHE_BYTES-1); end = ((unsigned long)start + size + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1); + nr_ways = current_cpu_data.dcache.ways; local_irq_save(flags); jump_to_uncached(); - for (v = begin; v < end; v+=L1_CACHE_BYTES) { - unsigned long addr = CACHE_OC_ADDRESS_ARRAY | (v & 0x000007f0); + /* If there are too many pages then flush the entire cache */ + if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) { + begin = CACHE_OC_ADDRESS_ARRAY; + end = begin + (nr_ways * current_cpu_data.dcache.way_size); + + for (v = begin; v < end; v += L1_CACHE_BYTES) { + unsigned long data = __raw_readl(v); + if (data & SH_CACHE_UPDATED) + __raw_writel(data & ~SH_CACHE_UPDATED, v); + } + } else { int way; - for (way = 0; way < 4; way++) { - unsigned long data = __raw_readl(addr | (way << 11)); - if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) { - data &= ~SH_CACHE_UPDATED; - __raw_writel(data, addr | (way << 11)); - } + for (way = 0; way < nr_ways; way++) { + for (v = begin; v < end; v += L1_CACHE_BYTES) + sh2a_flush_oc_line(v, way); } } back_to_cached(); local_irq_restore(flags); +#endif } +/* + * Write back the dirty D-caches and invalidate them. + */ static void sh2a__flush_purge_region(void *start, int size) { unsigned long v; @@ -58,13 +101,22 @@ static void sh2a__flush_purge_region(void *start, int size) jump_to_uncached(); for (v = begin; v < end; v+=L1_CACHE_BYTES) { - __raw_writel((v & CACHE_PHYSADDR_MASK), - CACHE_OC_ADDRESS_ARRAY | (v & 0x000007f0) | 0x00000008); +#ifdef CONFIG_CACHE_WRITEBACK + int way; + int nr_ways = current_cpu_data.dcache.ways; + for (way = 0; way < nr_ways; way++) + sh2a_flush_oc_line(v, way); +#endif + sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v); } + back_to_cached(); local_irq_restore(flags); } +/* + * Invalidate the D-caches, but no write back please + */ static void sh2a__flush_invalidate_region(void *start, int size) { unsigned long v; @@ -74,29 +126,25 @@ static void sh2a__flush_invalidate_region(void *start, int size) begin = (unsigned long)start & ~(L1_CACHE_BYTES-1); end = ((unsigned long)start + size + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1); + local_irq_save(flags); jump_to_uncached(); -#ifdef CONFIG_CACHE_WRITEBACK - __raw_writel(__raw_readl(CCR) | CCR_OCACHE_INVALIDATE, CCR); - /* I-cache invalidate */ - for (v = begin; v < end; v+=L1_CACHE_BYTES) { - __raw_writel((v & CACHE_PHYSADDR_MASK), - CACHE_IC_ADDRESS_ARRAY | (v & 0x000007f0) | 0x00000008); - } -#else - for (v = begin; v < end; v+=L1_CACHE_BYTES) { - __raw_writel((v & CACHE_PHYSADDR_MASK), - CACHE_IC_ADDRESS_ARRAY | (v & 0x000007f0) | 0x00000008); - __raw_writel((v & CACHE_PHYSADDR_MASK), - CACHE_OC_ADDRESS_ARRAY | (v & 0x000007f0) | 0x00000008); + /* If there are too many pages then just blow the cache */ + if (((end - begin) >> PAGE_SHIFT) >= MAX_OCACHE_PAGES) { + __raw_writel(__raw_readl(CCR) | CCR_OCACHE_INVALIDATE, CCR); + } else { + for (v = begin; v < end; v += L1_CACHE_BYTES) + sh2a_invalidate_line(CACHE_OC_ADDRESS_ARRAY, v); } -#endif + back_to_cached(); local_irq_restore(flags); } -/* WBack O-Cache and flush I-Cache */ +/* + * Write back the range of D-cache, and purge the I-cache. + */ static void sh2a_flush_icache_range(void *args) { struct flusher_data *data = args; @@ -107,23 +155,20 @@ static void sh2a_flush_icache_range(void *args) start = data->addr1 & ~(L1_CACHE_BYTES-1); end = (data->addr2 + L1_CACHE_BYTES-1) & ~(L1_CACHE_BYTES-1); +#ifdef CONFIG_CACHE_WRITEBACK + sh2a__flush_wback_region((void *)start, end-start); +#endif + local_irq_save(flags); jump_to_uncached(); - for (v = start; v < end; v+=L1_CACHE_BYTES) { - unsigned long addr = (v & 0x000007f0); - int way; - /* O-Cache writeback */ - for (way = 0; way < 4; way++) { - unsigned long data = __raw_readl(CACHE_OC_ADDRESS_ARRAY | addr | (way << 11)); - if ((data & CACHE_PHYSADDR_MASK) == (v & CACHE_PHYSADDR_MASK)) { - data &= ~SH_CACHE_UPDATED; - __raw_writel(data, CACHE_OC_ADDRESS_ARRAY | addr | (way << 11)); - } - } - /* I-Cache invalidate */ - __raw_writel(addr, - CACHE_IC_ADDRESS_ARRAY | addr | 0x00000008); + /* I-Cache invalidate */ + /* If there are too many pages then just blow the cache */ + if (((end - start) >> PAGE_SHIFT) >= MAX_ICACHE_PAGES) { + __raw_writel(__raw_readl(CCR) | CCR_ICACHE_INVALIDATE, CCR); + } else { + for (v = start; v < end; v += L1_CACHE_BYTES) + sh2a_invalidate_line(CACHE_IC_ADDRESS_ARRAY, v); } back_to_cached(); -- 2.20.1