diff options
Diffstat (limited to 'arch/arc/mm')
| -rw-r--r-- | arch/arc/mm/cache.c | 50 | ||||
| -rw-r--r-- | arch/arc/mm/dma.c | 45 | ||||
| -rw-r--r-- | arch/arc/mm/tlb.c | 12 |
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); } /* |