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-rw-r--r--arch/arc/mm/cache.c50
-rw-r--r--arch/arc/mm/dma.c45
-rw-r--r--arch/arc/mm/tlb.c12
3 files changed, 98 insertions, 9 deletions
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index a867575a758b..7db283b46ebd 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -665,6 +665,7 @@ noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
static DEFINE_SPINLOCK(lock);
unsigned long flags;
unsigned int ctrl;
+ phys_addr_t end;
spin_lock_irqsave(&lock, flags);
@@ -694,8 +695,19 @@ noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
* END needs to be setup before START (latter triggers the operation)
* END can't be same as START, so add (l2_line_sz - 1) to sz
*/
- write_aux_reg(ARC_REG_SLC_RGN_END, (paddr + sz + l2_line_sz - 1));
- write_aux_reg(ARC_REG_SLC_RGN_START, paddr);
+ end = paddr + sz + l2_line_sz - 1;
+ if (is_pae40_enabled())
+ write_aux_reg(ARC_REG_SLC_RGN_END1, upper_32_bits(end));
+
+ write_aux_reg(ARC_REG_SLC_RGN_END, lower_32_bits(end));
+
+ if (is_pae40_enabled())
+ write_aux_reg(ARC_REG_SLC_RGN_START1, upper_32_bits(paddr));
+
+ write_aux_reg(ARC_REG_SLC_RGN_START, lower_32_bits(paddr));
+
+ /* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
+ read_aux_reg(ARC_REG_SLC_CTRL);
while (read_aux_reg(ARC_REG_SLC_CTRL) & SLC_CTRL_BUSY);
@@ -1111,6 +1123,13 @@ noinline void __init arc_ioc_setup(void)
__dc_enable();
}
+/*
+ * Cache related boot time checks/setups only needed on master CPU:
+ * - Geometry checks (kernel build and hardware agree: e.g. L1_CACHE_BYTES)
+ * Assume SMP only, so all cores will have same cache config. A check on
+ * one core suffices for all
+ * - IOC setup / dma callbacks only need to be done once
+ */
void __init arc_cache_init_master(void)
{
unsigned int __maybe_unused cpu = smp_processor_id();
@@ -1190,12 +1209,27 @@ void __ref arc_cache_init(void)
printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
- /*
- * Only master CPU needs to execute rest of function:
- * - Assume SMP so all cores will have same cache config so
- * any geomtry checks will be same for all
- * - IOC setup / dma callbacks only need to be setup once
- */
if (!cpu)
arc_cache_init_master();
+
+ /*
+ * In PAE regime, TLB and cache maintenance ops take wider addresses
+ * And even if PAE is not enabled in kernel, the upper 32-bits still need
+ * to be zeroed to keep the ops sane.
+ * As an optimization for more common !PAE enabled case, zero them out
+ * once at init, rather than checking/setting to 0 for every runtime op
+ */
+ if (is_isa_arcv2() && pae40_exist_but_not_enab()) {
+
+ if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE))
+ write_aux_reg(ARC_REG_IC_PTAG_HI, 0);
+
+ if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE))
+ write_aux_reg(ARC_REG_DC_PTAG_HI, 0);
+
+ if (l2_line_sz) {
+ write_aux_reg(ARC_REG_SLC_RGN_END1, 0);
+ write_aux_reg(ARC_REG_SLC_RGN_START1, 0);
+ }
+ }
}
diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 71d3efff99d3..e9d93604ad0f 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -153,6 +153,19 @@ static void _dma_cache_sync(phys_addr_t paddr, size_t size,
}
}
+/*
+ * arc_dma_map_page - map a portion of a page for streaming DMA
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed. The CPU
+ * can regain ownership by calling dma_unmap_page().
+ *
+ * Note: while it takes struct page as arg, caller can "abuse" it to pass
+ * a region larger than PAGE_SIZE, provided it is physically contiguous
+ * and this still works correctly
+ */
static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size, enum dma_data_direction dir,
unsigned long attrs)
@@ -165,6 +178,24 @@ static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
return plat_phys_to_dma(dev, paddr);
}
+/*
+ * arc_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ *
+ * Note: historically this routine was not implemented for ARC
+ */
+static void arc_dma_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ phys_addr_t paddr = plat_dma_to_phys(dev, handle);
+
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ _dma_cache_sync(paddr, size, dir);
+}
+
static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
@@ -178,6 +209,18 @@ static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
return nents;
}
+static void arc_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ arc_dma_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir,
+ attrs);
+}
+
static void arc_dma_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
{
@@ -223,7 +266,9 @@ const struct dma_map_ops arc_dma_ops = {
.free = arc_dma_free,
.mmap = arc_dma_mmap,
.map_page = arc_dma_map_page,
+ .unmap_page = arc_dma_unmap_page,
.map_sg = arc_dma_map_sg,
+ .unmap_sg = arc_dma_unmap_sg,
.sync_single_for_device = arc_dma_sync_single_for_device,
.sync_single_for_cpu = arc_dma_sync_single_for_cpu,
.sync_sg_for_cpu = arc_dma_sync_sg_for_cpu,
diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
index d0126fdfe2d8..b181f3ee38aa 100644
--- a/arch/arc/mm/tlb.c
+++ b/arch/arc/mm/tlb.c
@@ -104,6 +104,8 @@
/* A copy of the ASID from the PID reg is kept in asid_cache */
DEFINE_PER_CPU(unsigned int, asid_cache) = MM_CTXT_FIRST_CYCLE;
+static int __read_mostly pae_exists;
+
/*
* Utility Routine to erase a J-TLB entry
* Caller needs to setup Index Reg (manually or via getIndex)
@@ -784,7 +786,7 @@ void read_decode_mmu_bcr(void)
mmu->u_dtlb = mmu4->u_dtlb * 4;
mmu->u_itlb = mmu4->u_itlb * 4;
mmu->sasid = mmu4->sasid;
- mmu->pae = mmu4->pae;
+ pae_exists = mmu->pae = mmu4->pae;
}
}
@@ -809,6 +811,11 @@ char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len)
return buf;
}
+int pae40_exist_but_not_enab(void)
+{
+ return pae_exists && !is_pae40_enabled();
+}
+
void arc_mmu_init(void)
{
char str[256];
@@ -859,6 +866,9 @@ void arc_mmu_init(void)
/* swapper_pg_dir is the pgd for the kernel, used by vmalloc */
write_aux_reg(ARC_REG_SCRATCH_DATA0, swapper_pg_dir);
#endif
+
+ if (pae40_exist_but_not_enab())
+ write_aux_reg(ARC_REG_TLBPD1HI, 0);
}
/*