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authorKamal Dasu <kdasu.kdev@gmail.com>2020-02-07 17:33:07 -0500
committerThomas Bogendoerfer <tsbogend@alpha.franken.de>2020-03-16 16:09:56 +0100
commitbe2807643302bb4161b6c009f569e63f0f79672c (patch)
treee16ecf5ff18566f37ff009843a8b0894f0bd5627 /arch/mips
parentMIPS: pass non-NULL dev_id on shared request_irq() (diff)
downloadlinux-dev-be2807643302bb4161b6c009f569e63f0f79672c.tar.xz
linux-dev-be2807643302bb4161b6c009f569e63f0f79672c.zip
MIPS: c-r4k: Invalidate BMIPS5000 ZSCM prefetch lines
Zephyr secondary cache is 256KB, 128B lines. 32B sectors. A secondary cache line can contain two instruction cache lines (64B), or four data cache lines (32B). Hardware prefetch Cache detects stream access, and prefetches ahead of processor access. Add support to invalidate BMIPS5000 cpu zephyr secondary cache module (ZSCM) on DMA from device so that data returned is coherent during DMA read operations. Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Diffstat (limited to 'arch/mips')
-rw-r--r--arch/mips/mm/c-r4k.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 3472f6deaf92..36a311348739 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -901,6 +901,31 @@ static void r4k_dma_cache_wback_inv(unsigned long addr, unsigned long size)
__sync();
}
+static void prefetch_cache_inv(unsigned long addr, unsigned long size)
+{
+ unsigned int linesz = cpu_scache_line_size();
+ unsigned long addr0 = addr, addr1;
+
+ addr0 &= ~(linesz - 1);
+ addr1 = (addr0 + size - 1) & ~(linesz - 1);
+
+ protected_writeback_scache_line(addr0);
+ if (likely(addr1 != addr0))
+ protected_writeback_scache_line(addr1);
+ else
+ return;
+
+ addr0 += linesz;
+ if (likely(addr1 != addr0))
+ protected_writeback_scache_line(addr0);
+ else
+ return;
+
+ addr1 -= linesz;
+ if (likely(addr1 > addr0))
+ protected_writeback_scache_line(addr0);
+}
+
static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
{
/* Catch bad driver code */
@@ -908,6 +933,10 @@ static void r4k_dma_cache_inv(unsigned long addr, unsigned long size)
return;
preempt_disable();
+
+ if (current_cpu_type() == CPU_BMIPS5000)
+ prefetch_cache_inv(addr, size);
+
if (cpu_has_inclusive_pcaches) {
if (size >= scache_size) {
if (current_cpu_type() != CPU_LOONGSON64)