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Diffstat (limited to 'arch/arc/mm/cache.c')
-rw-r--r--arch/arc/mm/cache.c53
1 files changed, 35 insertions, 18 deletions
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index 9dbe645ee127..f2701c13a66b 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -65,7 +65,7 @@ char *arc_cache_mumbojumbo(int c, char *buf, int len)
n += scnprintf(buf + n, len - n, "Peripherals\t: %#lx%s%s\n",
perip_base,
- IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency "));
+ IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency (per-device) "));
return buf;
}
@@ -897,15 +897,6 @@ static void __dma_cache_wback_slc(phys_addr_t start, unsigned long sz)
}
/*
- * DMA ops for systems with IOC
- * IOC hardware snoops all DMA traffic keeping the caches consistent with
- * memory - eliding need for any explicit cache maintenance of DMA buffers
- */
-static void __dma_cache_wback_inv_ioc(phys_addr_t start, unsigned long sz) {}
-static void __dma_cache_inv_ioc(phys_addr_t start, unsigned long sz) {}
-static void __dma_cache_wback_ioc(phys_addr_t start, unsigned long sz) {}
-
-/*
* Exported DMA API
*/
void dma_cache_wback_inv(phys_addr_t start, unsigned long sz)
@@ -1038,7 +1029,7 @@ void flush_cache_mm(struct mm_struct *mm)
void flush_cache_page(struct vm_area_struct *vma, unsigned long u_vaddr,
unsigned long pfn)
{
- unsigned int paddr = pfn << PAGE_SHIFT;
+ phys_addr_t paddr = pfn << PAGE_SHIFT;
u_vaddr &= PAGE_MASK;
@@ -1058,8 +1049,9 @@ void flush_anon_page(struct vm_area_struct *vma, struct page *page,
unsigned long u_vaddr)
{
/* TBD: do we really need to clear the kernel mapping */
- __flush_dcache_page(page_address(page), u_vaddr);
- __flush_dcache_page(page_address(page), page_address(page));
+ __flush_dcache_page((phys_addr_t)page_address(page), u_vaddr);
+ __flush_dcache_page((phys_addr_t)page_address(page),
+ (phys_addr_t)page_address(page));
}
@@ -1152,6 +1144,19 @@ noinline void __init arc_ioc_setup(void)
{
unsigned int ioc_base, mem_sz;
+ /*
+ * As for today we don't support both IOC and ZONE_HIGHMEM enabled
+ * simultaneously. This happens because as of today IOC aperture covers
+ * only ZONE_NORMAL (low mem) and any dma transactions outside this
+ * region won't be HW coherent.
+ * If we want to use both IOC and ZONE_HIGHMEM we can use
+ * bounce_buffer to handle dma transactions to HIGHMEM.
+ * Also it is possible to modify dma_direct cache ops or increase IOC
+ * aperture size if we are planning to use HIGHMEM without PAE.
+ */
+ if (IS_ENABLED(CONFIG_HIGHMEM))
+ panic("IOC and HIGHMEM can't be used simultaneously");
+
/* Flush + invalidate + disable L1 dcache */
__dc_disable();
@@ -1246,6 +1251,16 @@ void __init arc_cache_init_master(void)
}
}
+ /*
+ * Check that SMP_CACHE_BYTES (and hence ARCH_DMA_MINALIGN) is larger
+ * or equal to any cache line length.
+ */
+ BUILD_BUG_ON_MSG(L1_CACHE_BYTES > SMP_CACHE_BYTES,
+ "SMP_CACHE_BYTES must be >= any cache line length");
+ if (is_isa_arcv2() && (l2_line_sz > SMP_CACHE_BYTES))
+ panic("L2 Cache line [%d] > kernel Config [%d]\n",
+ l2_line_sz, SMP_CACHE_BYTES);
+
/* Note that SLC disable not formally supported till HS 3.0 */
if (is_isa_arcv2() && l2_line_sz && !slc_enable)
arc_slc_disable();
@@ -1253,11 +1268,7 @@ void __init arc_cache_init_master(void)
if (is_isa_arcv2() && ioc_enable)
arc_ioc_setup();
- if (is_isa_arcv2() && ioc_enable) {
- __dma_cache_wback_inv = __dma_cache_wback_inv_ioc;
- __dma_cache_inv = __dma_cache_inv_ioc;
- __dma_cache_wback = __dma_cache_wback_ioc;
- } else if (is_isa_arcv2() && l2_line_sz && slc_enable) {
+ if (is_isa_arcv2() && l2_line_sz && slc_enable) {
__dma_cache_wback_inv = __dma_cache_wback_inv_slc;
__dma_cache_inv = __dma_cache_inv_slc;
__dma_cache_wback = __dma_cache_wback_slc;
@@ -1266,6 +1277,12 @@ void __init arc_cache_init_master(void)
__dma_cache_inv = __dma_cache_inv_l1;
__dma_cache_wback = __dma_cache_wback_l1;
}
+ /*
+ * In case of IOC (say IOC+SLC case), pointers above could still be set
+ * but end up not being relevant as the first function in chain is not
+ * called at all for @dma_direct_ops
+ * arch_sync_dma_for_cpu() -> dma_cache_*() -> __dma_cache_*()
+ */
}
void __ref arc_cache_init(void)