[U-Boot] [PATCH v4] arm: cache: always flush cache line size for page table
Stefan Agner
stefan at agner.ch
Sun Aug 7 19:43:00 CEST 2016
From: Stefan Agner <stefan.agner at toradex.com>
The page table is maintained by the CPU, hence it is safe to always
align cache flush to a whole cache line size. This allows to use
mmu_page_table_flush for a single page table, e.g. when configure
only small regions through mmu_set_region_dcache_behaviour.
Signed-off-by: Stefan Agner <stefan.agner at toradex.com>
Tested-by: Fabio Estevam <fabio.estevam at nxp.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
---
Changes in v4:
- Fixed spelling misstake for real
Changes in v3:
- Fixed spelling misstake
Changes in v2:
- Move cache line alignment from mmu_page_table_flush to
mmu_set_region_dcache_behaviour
arch/arm/lib/cache-cp15.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c
index 1121dc3..488094e 100644
--- a/arch/arm/lib/cache-cp15.c
+++ b/arch/arm/lib/cache-cp15.c
@@ -62,6 +62,7 @@ void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
enum dcache_option option)
{
u32 *page_table = (u32 *)gd->arch.tlb_addr;
+ phys_addr_t startpt, stoppt;
unsigned long upto, end;
end = ALIGN(start + size, MMU_SECTION_SIZE) >> MMU_SECTION_SHIFT;
@@ -70,7 +71,17 @@ void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
option);
for (upto = start; upto < end; upto++)
set_section_dcache(upto, option);
- mmu_page_table_flush((u32)&page_table[start], (u32)&page_table[end]);
+
+ /*
+ * Make sure range is cache line aligned
+ * Only CPU maintains page tables, hence it is safe to always
+ * flush complete cache lines...
+ */
+ startpt = (phys_addr_t)&page_table[start];
+ startpt &= ~(CONFIG_SYS_CACHELINE_SIZE - 1);
+ stoppt = (phys_addr_t)&page_table[end];
+ stoppt = ALIGN(stoppt, CONFIG_SYS_CACHELINE_SIZE);
+ mmu_page_table_flush(startpt, stoppt);
}
__weak void dram_bank_mmu_setup(int bank)
--
2.9.0
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