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Diffstat (limited to 'arch/arc/mm/cache_arc700.c')
| -rw-r--r-- | arch/arc/mm/cache_arc700.c | 748 |
1 files changed, 748 insertions, 0 deletions
diff --git a/arch/arc/mm/cache_arc700.c b/arch/arc/mm/cache_arc700.c new file mode 100644 index 00000000000..2f12bca8aef --- /dev/null +++ b/arch/arc/mm/cache_arc700.c @@ -0,0 +1,748 @@ +/* + * ARC700 VIPT Cache Management + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * vineetg: May 2011: for Non-aliasing VIPT D-cache following can be NOPs + * -flush_cache_dup_mm (fork) + * -likewise for flush_cache_mm (exit/execve) + * -likewise for flush_cache_range,flush_cache_page (munmap, exit, COW-break) + * + * vineetg: Apr 2011 + * -Now that MMU can support larger pg sz (16K), the determiniation of + * aliasing shd not be based on assumption of 8k pg + * + * vineetg: Mar 2011 + * -optimised version of flush_icache_range( ) for making I/D coherent + * when vaddr is available (agnostic of num of aliases) + * + * vineetg: Mar 2011 + * -Added documentation about I-cache aliasing on ARC700 and the way it + * was handled up until MMU V2. + * -Spotted a three year old bug when killing the 4 aliases, which needs + * bottom 2 bits, so we need to do paddr | {0x00, 0x01, 0x02, 0x03} + * instead of paddr | {0x00, 0x01, 0x10, 0x11} + * (Rajesh you owe me one now) + * + * vineetg: Dec 2010 + * -Off-by-one error when computing num_of_lines to flush + * This broke signal handling with bionic which uses synthetic sigret stub + * + * vineetg: Mar 2010 + * -GCC can't generate ZOL for core cache flush loops. + * Conv them into iterations based as opposed to while (start < end) types + * + * Vineetg: July 2009 + * -In I-cache flush routine we used to chk for aliasing for every line INV. + * Instead now we setup routines per cache geometry and invoke them + * via function pointers. + * + * Vineetg: Jan 2009 + * -Cache Line flush routines used to flush an extra line beyond end addr + * because check was while (end >= start) instead of (end > start) + * =Some call sites had to work around by doing -1, -4 etc to end param + * =Some callers didnt care. This was spec bad in case of INV routines + * which would discard valid data (cause of the horrible ext2 bug + * in ARC IDE driver) + * + * vineetg: June 11th 2008: Fixed flush_icache_range( ) + * -Since ARC700 caches are not coherent (I$ doesnt snoop D$) both need + * to be flushed, which it was not doing. + * -load_module( ) passes vmalloc addr (Kernel Virtual Addr) to the API, + * however ARC cache maintenance OPs require PHY addr. Thus need to do + * vmalloc_to_phy. + * -Also added optimisation there, that for range > PAGE SIZE we flush the + * entire cache in one shot rather than line by line. For e.g. a module + * with Code sz 600k, old code flushed 600k worth of cache (line-by-line), + * while cache is only 16 or 32k. + */ + +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/cache.h> +#include <linux/mmu_context.h> +#include <linux/syscalls.h> +#include <linux/uaccess.h> +#include <linux/pagemap.h> +#include <asm/cacheflush.h> +#include <asm/cachectl.h> +#include <asm/setup.h> + +char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len) +{ + int n = 0; + unsigned int c = smp_processor_id(); + +#define PR_CACHE(p, enb, str) \ +{ \ + if (!(p)->ver) \ + n += scnprintf(buf + n, len - n, str"\t\t: N/A\n"); \ + else \ + n += scnprintf(buf + n, len - n, \ + str"\t\t: (%uK) VIPT, %dway set-asc, %ub Line %s\n", \ + TO_KB((p)->sz), (p)->assoc, (p)->line_len, \ + enb ? "" : "DISABLED (kernel-build)"); \ +} + + PR_CACHE(&cpuinfo_arc700[c].icache, __CONFIG_ARC_HAS_ICACHE, "I-Cache"); + PR_CACHE(&cpuinfo_arc700[c].dcache, __CONFIG_ARC_HAS_DCACHE, "D-Cache"); + + return buf; +} + +/* + * Read the Cache Build Confuration Registers, Decode them and save into + * the cpuinfo structure for later use. + * No Validation done here, simply read/convert the BCRs + */ +void __cpuinit read_decode_cache_bcr(void) +{ + struct bcr_cache ibcr, dbcr; + struct cpuinfo_arc_cache *p_ic, *p_dc; + unsigned int cpu = smp_processor_id(); + + p_ic = &cpuinfo_arc700[cpu].icache; + READ_BCR(ARC_REG_IC_BCR, ibcr); + + if (ibcr.config == 0x3) + p_ic->assoc = 2; + p_ic->line_len = 8 << ibcr.line_len; + p_ic->sz = 0x200 << ibcr.sz; + p_ic->ver = ibcr.ver; + + p_dc = &cpuinfo_arc700[cpu].dcache; + READ_BCR(ARC_REG_DC_BCR, dbcr); + + if (dbcr.config == 0x2) + p_dc->assoc = 4; + p_dc->line_len = 16 << dbcr.line_len; + p_dc->sz = 0x200 << dbcr.sz; + p_dc->ver = dbcr.ver; +} + +/* + * 1. Validate the Cache Geomtery (compile time config matches hardware) + * 2. If I-cache suffers from aliasing, setup work arounds (difft flush rtn) + * (aliasing D-cache configurations are not supported YET) + * 3. Enable the Caches, setup default flush mode for D-Cache + * 3. Calculate the SHMLBA used by user space + */ +void __cpuinit arc_cache_init(void) +{ + unsigned int temp; + unsigned int cpu = smp_processor_id(); + struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache; + struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache; + int way_pg_ratio = way_pg_ratio; + int dcache_does_alias; + char str[256]; + + printk(arc_cache_mumbojumbo(0, str, sizeof(str))); + + if (!ic->ver) + goto chk_dc; + +#ifdef CONFIG_ARC_HAS_ICACHE + /* 1. Confirm some of I-cache params which Linux assumes */ + if ((ic->assoc != ARC_ICACHE_WAYS) || + (ic->line_len != ARC_ICACHE_LINE_LEN)) { + panic("Cache H/W doesn't match kernel Config"); + } +#if (CONFIG_ARC_MMU_VER > 2) + if (ic->ver != 3) { + if (running_on_hw) + panic("Cache ver doesn't match MMU ver\n"); + + /* For ISS - suggest the toggles to use */ + pr_err("Use -prop=icache_version=3,-prop=dcache_version=3\n"); + + } +#endif +#endif + + /* Enable/disable I-Cache */ + temp = read_aux_reg(ARC_REG_IC_CTRL); + +#ifdef CONFIG_ARC_HAS_ICACHE + temp &= ~IC_CTRL_CACHE_DISABLE; +#else + temp |= IC_CTRL_CACHE_DISABLE; +#endif + + write_aux_reg(ARC_REG_IC_CTRL, temp); + +chk_dc: + if (!dc->ver) + return; + +#ifdef CONFIG_ARC_HAS_DCACHE + if ((dc->assoc != ARC_DCACHE_WAYS) || + (dc->line_len != ARC_DCACHE_LINE_LEN)) { + panic("Cache H/W doesn't match kernel Config"); + } + + dcache_does_alias = (dc->sz / ARC_DCACHE_WAYS) > PAGE_SIZE; + + /* check for D-Cache aliasing */ + if (dcache_does_alias && !cache_is_vipt_aliasing()) + panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n"); + else if (!dcache_does_alias && cache_is_vipt_aliasing()) + panic("Don't need CONFIG_ARC_CACHE_VIPT_ALIASING\n"); +#endif + + /* Set the default Invalidate Mode to "simpy discard dirty lines" + * as this is more frequent then flush before invalidate + * Ofcourse we toggle this default behviour when desired + */ + temp = read_aux_reg(ARC_REG_DC_CTRL); + temp &= ~DC_CTRL_INV_MODE_FLUSH; + +#ifdef CONFIG_ARC_HAS_DCACHE + /* Enable D-Cache: Clear Bit 0 */ + write_aux_reg(ARC_REG_DC_CTRL, temp & ~IC_CTRL_CACHE_DISABLE); +#else + /* Flush D cache */ + write_aux_reg(ARC_REG_DC_FLSH, 0x1); + /* Disable D cache */ + write_aux_reg(ARC_REG_DC_CTRL, temp | IC_CTRL_CACHE_DISABLE); +#endif + + return; +} + +#define OP_INV 0x1 +#define OP_FLUSH 0x2 +#define OP_FLUSH_N_INV 0x3 + +#ifdef CONFIG_ARC_HAS_DCACHE + +/*************************************************************** + * Machine specific helpers for Entire D-Cache or Per Line ops + */ + +static inline void wait_for_flush(void) +{ + while (read_aux_reg(ARC_REG_DC_CTRL) & DC_CTRL_FLUSH_STATUS) + ; +} + +/* + * Operation on Entire D-Cache + * @cacheop = {OP_INV, OP_FLUSH, OP_FLUSH_N_INV} + * Note that constant propagation ensures all the checks are gone + * in generated code + */ +static inline void __dc_entire_op(const int cacheop) +{ + unsigned long flags, tmp = tmp; + int aux; + + local_irq_save(flags); + + if (cacheop == OP_FLUSH_N_INV) { + /* Dcache provides 2 cmd: FLUSH or INV + * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE + * flush-n-inv is achieved by INV cmd but with IM=1 + * Default INV sub-mode is DISCARD, which needs to be toggled + */ + tmp = read_aux_reg(ARC_REG_DC_CTRL); + write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH); + } + + if (cacheop & OP_INV) /* Inv or flush-n-inv use same cmd reg */ + aux = ARC_REG_DC_IVDC; + else + aux = ARC_REG_DC_FLSH; + + write_aux_reg(aux, 0x1); + + if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */ + wait_for_flush(); + + /* Switch back the DISCARD ONLY Invalidate mode */ + if (cacheop == OP_FLUSH_N_INV) + write_aux_reg(ARC_REG_DC_CTRL, tmp & ~DC_CTRL_INV_MODE_FLUSH); + + local_irq_restore(flags); +} + +/* + * Per Line Operation on D-Cache + * Doesn't deal with type-of-op/IRQ-disabling/waiting-for-flush-to-complete + * It's sole purpose is to help gcc generate ZOL + * (aliasing VIPT dcache flushing needs both vaddr and paddr) + */ +static inline void __dc_line_loop(unsigned long paddr, unsigned long vaddr, + unsigned long sz, const int aux_reg) +{ + int num_lines; + + /* Ensure we properly floor/ceil the non-line aligned/sized requests + * and have @paddr - aligned to cache line and integral @num_lines. + * This however can be avoided for page sized since: + * -@paddr will be cache-line aligned already (being page aligned) + * -@sz will be integral multiple of line size (being page sized). + */ + if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) { + sz += paddr & ~DCACHE_LINE_MASK; + paddr &= DCACHE_LINE_MASK; + vaddr &= DCACHE_LINE_MASK; + } + + num_lines = DIV_ROUND_UP(sz, ARC_DCACHE_LINE_LEN); + +#if (CONFIG_ARC_MMU_VER <= 2) + paddr |= (vaddr >> PAGE_SHIFT) & 0x1F; +#endif + + while (num_lines-- > 0) { +#if (CONFIG_ARC_MMU_VER > 2) + /* + * Just as for I$, in MMU v3, D$ ops also require + * "tag" bits in DC_PTAG, "index" bits in FLDL,IVDL ops + */ + write_aux_reg(ARC_REG_DC_PTAG, paddr); + + write_aux_reg(aux_reg, vaddr); + vaddr += ARC_DCACHE_LINE_LEN; +#else + /* paddr contains stuffed vaddrs bits */ + write_aux_reg(aux_reg, paddr); +#endif + paddr += ARC_DCACHE_LINE_LEN; + } +} + +/* For kernel mappings cache operation: index is same as paddr */ +#define __dc_line_op_k(p, sz, op) __dc_line_op(p, p, sz, op) + +/* + * D-Cache : Per Line INV (discard or wback+discard) or FLUSH (wback) + */ +static inline void __dc_line_op(unsigned long paddr, unsigned long vaddr, + unsigned long sz, const int cacheop) +{ + unsigned long flags, tmp = tmp; + int aux; + + local_irq_save(flags); + + if (cacheop == OP_FLUSH_N_INV) { + /* + * Dcache provides 2 cmd: FLUSH or INV + * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE + * flush-n-inv is achieved by INV cmd but with IM=1 + * Default INV sub-mode is DISCARD, which needs to be toggled + */ + tmp = read_aux_reg(ARC_REG_DC_CTRL); + write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH); + } + + if (cacheop & OP_INV) /* Inv / flush-n-inv use same cmd reg */ + aux = ARC_REG_DC_IVDL; + else + aux = ARC_REG_DC_FLDL; + + __dc_line_loop(paddr, vaddr, sz, aux); + + if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */ + wait_for_flush(); + + /* Switch back the DISCARD ONLY Invalidate mode */ + if (cacheop == OP_FLUSH_N_INV) + write_aux_reg(ARC_REG_DC_CTRL, tmp & ~DC_CTRL_INV_MODE_FLUSH); + + local_irq_restore(flags); +} + +#else + +#define __dc_entire_op(cacheop) +#define __dc_line_op(paddr, vaddr, sz, cacheop) +#define __dc_line_op_k(paddr, sz, cacheop) + +#endif /* CONFIG_ARC_HAS_DCACHE */ + + +#ifdef CONFIG_ARC_HAS_ICACHE + +/* + * I-Cache Aliasing in ARC700 VIPT caches + * + * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag. + * The orig Cache Management Module "CDU" only required paddr to invalidate a + * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry. + * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching + * the exact same line. + * + * However for larger Caches (way-size > page-size) - i.e. in Aliasing config, + * paddr alone could not be used to correctly index the cache. + * + * ------------------ + * MMU v1/v2 (Fixed Page Size 8k) + * ------------------ + * The solution was to provide CDU with these additonal vaddr bits. These + * would be bits [x:13], x would depend on cache-geometry, 13 comes from + * standard page size of 8k. + * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits + * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the + * orig 5 bits of paddr were anyways ignored by CDU line ops, as they + * represent the offset within cache-line. The adv of using this "clumsy" + * interface for additional info was no new reg was needed in CDU programming + * model. + * + * 17:13 represented the max num of bits passable, actual bits needed were + * fewer, based on the num-of-aliases possible. + * -for 2 alias possibility, only bit 13 needed (32K cache) + * -for 4 alias possibility, bits 14:13 needed (64K cache) + * + * ------------------ + * MMU v3 + * ------------------ + * This ver of MMU supports variable page sizes (1k-16k): although Linux will + * only support 8k (default), 16k and 4k. + * However from hardware perspective, smaller page sizes aggrevate aliasing + * meaning more vaddr bits needed to disambiguate the cache-line-op ; + * the existing scheme of piggybacking won't work for certain configurations. + * Two new registers IC_PTAG and DC_PTAG inttoduced. + * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs + */ + +/*********************************************************** + * Machine specific helper for per line I-Cache invalidate. + */ +static void __ic_line_inv_vaddr(unsigned long paddr, unsigned long vaddr, + unsigned long sz) +{ + unsigned long flags; + int num_lines; + + /* + * Ensure we properly floor/ceil the non-line aligned/sized requests: + * However page sized flushes can be compile time optimised. + * -@paddr will be cache-line aligned already (being page aligned) + * -@sz will be integral multiple of line size (being page sized). + */ + if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) { + sz += paddr & ~ICACHE_LINE_MASK; + paddr &= ICACHE_LINE_MASK; + vaddr &= ICACHE_LINE_MASK; + } + + num_lines = DIV_ROUND_UP(sz, ARC_ICACHE_LINE_LEN); + +#if (CONFIG_ARC_MMU_VER <= 2) + /* bits 17:13 of vaddr go as bits 4:0 of paddr */ + paddr |= (vaddr >> PAGE_SHIFT) & 0x1F; +#endif + + local_irq_save(flags); + while (num_lines-- > 0) { +#if (CONFIG_ARC_MMU_VER > 2) + /* tag comes from phy addr */ + write_aux_reg(ARC_REG_IC_PTAG, paddr); + + /* index bits come from vaddr */ + write_aux_reg(ARC_REG_IC_IVIL, vaddr); + vaddr += ARC_ICACHE_LINE_LEN; +#else + /* paddr contains stuffed vaddrs bits */ + write_aux_reg(ARC_REG_IC_IVIL, paddr); +#endif + paddr += ARC_ICACHE_LINE_LEN; + } + local_irq_restore(flags); +} + +#else + +#define __ic_line_inv_vaddr(pstart, vstart, sz) + +#endif /* CONFIG_ARC_HAS_ICACHE */ + + +/*********************************************************** + * Exported APIs + */ + +/* + * Handle cache congruency of kernel and userspace mappings of page when kernel + * writes-to/reads-from + * + * The idea is to defer flushing of kernel mapping after a WRITE, possible if: + * -dcache is NOT aliasing, hence any U/K-mappings of page are congruent + * -U-mapping doesn't exist yet for page (finalised in update_mmu_cache) + * -In SMP, if hardware caches are coherent + * + * There's a corollary case, where kernel READs from a userspace mapped page. + * If the U-mapping is not congruent to to K-mapping, former needs flushing. + */ +void flush_dcache_page(struct page *page) +{ + struct address_space *mapping; + + if (!cache_is_vipt_aliasing()) { + set_bit(PG_arch_1, &page->flags); + return; + } + + /* don't handle anon pages here */ + mapping = page_mapping(page); + if (!mapping) + return; + + /* + * pagecache page, file not yet mapped to userspace + * Make a note that K-mapping is dirty + */ + if (!mapping_mapped(mapping)) { + set_bit(PG_arch_1, &page->flags); + } else if (page_mapped(page)) { + + /* kernel reading from page with U-mapping */ + void *paddr = page_address(page); + unsigned long vaddr = page->index << PAGE_CACHE_SHIFT; + + if (addr_not_cache_congruent(paddr, vaddr)) + __flush_dcache_page(paddr, vaddr); + } +} +EXPORT_SYMBOL(flush_dcache_page); + + +void dma_cache_wback_inv(unsigned long start, unsigned long sz) +{ + __dc_line_op_k(start, sz, OP_FLUSH_N_INV); +} +EXPORT_SYMBOL(dma_cache_wback_inv); + +void dma_cache_inv(unsigned long start, unsigned long sz) +{ + __dc_line_op_k(start, sz, OP_INV); +} +EXPORT_SYMBOL(dma_cache_inv); + +void dma_cache_wback(unsigned long start, unsigned long sz) +{ + __dc_line_op_k(start, sz, OP_FLUSH); +} +EXPORT_SYMBOL(dma_cache_wback); + +/* + * This is API for making I/D Caches consistent when modifying + * kernel code (loadable modules, kprobes, kgdb...) + * This is called on insmod, with kernel virtual address for CODE of + * the module. ARC cache maintenance ops require PHY address thus we + * need to convert vmalloc addr to PHY addr + */ +void flush_icache_range(unsigned long kstart, unsigned long kend) +{ + unsigned int tot_sz, off, sz; + unsigned long phy, pfn; + + /* printk("Kernel Cache Cohenercy: %lx to %lx\n",kstart, kend); */ + + /* This is not the right API for user virtual address */ + if (kstart < TASK_SIZE) { + BUG_ON("Flush icache range for user virtual addr space"); + return; + } + + /* Shortcut for bigger flush ranges. + * Here we don't care if this was kernel virtual or phy addr + */ + tot_sz = kend - kstart; + if (tot_sz > PAGE_SIZE) { + flush_cache_all(); + return; + } + + /* Case: Kernel Phy addr (0x8000_0000 onwards) */ + if (likely(kstart > PAGE_OFFSET)) { + /* + * The 2nd arg despite being paddr will be used to index icache + * This is OK since no alternate virtual mappings will exist + * given the callers for this case: kprobe/kgdb in built-in + * kernel code only. + */ + __sync_icache_dcache(kstart, kstart, kend - kstart); + return; + } + + /* + * Case: Kernel Vaddr (0x7000_0000 to 0x7fff_ffff) + * (1) ARC Cache Maintenance ops only take Phy addr, hence special + * handling of kernel vaddr. + * + * (2) Despite @tot_sz being < PAGE_SIZE (bigger cases handled already), + * it still needs to handle a 2 page scenario, where the range + * straddles across 2 virtual pages and hence need for loop + */ + while (tot_sz > 0) { + off = kstart % PAGE_SIZE; + pfn = vmalloc_to_pfn((void *)kstart); + phy = (pfn << PAGE_SHIFT) + off; + sz = min_t(unsigned int, tot_sz, PAGE_SIZE - off); + __sync_icache_dcache(phy, kstart, sz); + kstart += sz; + tot_sz -= sz; + } +} + +/* + * General purpose helper to make I and D cache lines consistent. + * @paddr is phy addr of region + * @vaddr is typically user or kernel vaddr (vmalloc) + * Howver in one instance, flush_icache_range() by kprobe (for a breakpt in + * builtin kernel code) @vaddr will be paddr only, meaning CDU operation will + * use a paddr to index the cache (despite VIPT). This is fine since since a + * built-in kernel page will not have any virtual mappings (not even kernel) + * kprobe on loadable module is different as it will have kvaddr. + */ +void __sync_icache_dcache(unsigned long paddr, unsigned long vaddr, int len) +{ + unsigned long flags; + + local_irq_save(flags); + __ic_line_inv_vaddr(paddr, vaddr, len); + __dc_line_op(paddr, vaddr, len, OP_FLUSH); + local_irq_restore(flags); +} + +/* wrapper to compile time eliminate alignment checks in flush loop */ +void __inv_icache_page(unsigned long paddr, unsigned long vaddr) +{ + __ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE); +} + +/* + * wrapper to clearout kernel or userspace mappings of a page + * For kernel mappings @vaddr == @paddr + */ +void ___flush_dcache_page(unsigned long paddr, unsigned long vaddr) +{ + __dc_line_op(paddr, vaddr & PAGE_MASK, PAGE_SIZE, OP_FLUSH_N_INV); +} + +void flush_icache_all(void) +{ + unsigned long flags; + + local_irq_save(flags); + + write_aux_reg(ARC_REG_IC_IVIC, 1); + + /* lr will not complete till the icache inv operation is not over */ + read_aux_reg(ARC_REG_IC_CTRL); + local_irq_restore(flags); +} + +noinline void flush_cache_all(void) +{ + unsigned long flags; + + local_irq_save(flags); + + flush_icache_all(); + __dc_entire_op(OP_FLUSH_N_INV); + + local_irq_restore(flags); + +} + +#ifdef CONFIG_ARC_CACHE_VIPT_ALIASING + +void flush_cache_mm(struct mm_struct *mm) +{ + flush_cache_all(); +} + +void flush_cache_page(struct vm_area_struct *vma, unsigned long u_vaddr, + unsigned long pfn) +{ + unsigned int paddr = pfn << PAGE_SHIFT; + + __sync_icache_dcache(paddr, u_vaddr, PAGE_SIZE); +} + +void flush_cache_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + flush_cache_all(); +} + +void copy_user_highpage(struct page *to, struct page *from, + unsigned long u_vaddr, struct vm_area_struct *vma) +{ + void *kfrom = page_address(from); + void *kto = page_address(to); + int clean_src_k_mappings = 0; + + /* + * If SRC page was already mapped in userspace AND it's U-mapping is + * not congruent with K-mapping, sync former to physical page so that + * K-mapping in memcpy below, sees the right data + * + * Note that while @u_vaddr refers to DST page's userspace vaddr, it is + * equally valid for SRC page as well + */ + if (page_mapped(from) && addr_not_cache_congruent(kfrom, u_vaddr)) { + __flush_dcache_page(kfrom, u_vaddr); + clean_src_k_mappings = 1; + } + + copy_page(kto, kfrom); + + /* + * Mark DST page K-mapping as dirty for a later finalization by + * update_mmu_cache(). Although the finalization could have been done + * here as well (given that both vaddr/paddr are available). + * But update_mmu_cache() already has code to do that for other + * non copied user pages (e.g. read faults which wire in pagecache page + * directly). + */ + set_bit(PG_arch_1, &to->flags); + + /* + * if SRC was already usermapped and non-congruent to kernel mapping + * sync the kernel mapping back to physical page + */ + if (clean_src_k_mappings) { + __flush_dcache_page(kfrom, kfrom); + } else { + set_bit(PG_arch_1, &from->flags); + } +} + +void clear_user_page(void *to, unsigned long u_vaddr, struct page *page) +{ + clear_page(to); + set_bit(PG_arch_1, &page->flags); +} + +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)); + +} + +#endif + +/********************************************************************** + * Explicit Cache flush request from user space via syscall + * Needed for JITs which generate code on the fly + */ +SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags) +{ + /* TBD: optimize this */ + flush_cache_all(); + return 0; +} |