diff options
Diffstat (limited to 'arch/arc/mm/cache_arc700.c')
| -rw-r--r-- | arch/arc/mm/cache_arc700.c | 676 |
1 files changed, 305 insertions, 371 deletions
diff --git a/arch/arc/mm/cache_arc700.c b/arch/arc/mm/cache_arc700.c index 88d617d8423..353b202c37c 100644 --- a/arch/arc/mm/cache_arc700.c +++ b/arch/arc/mm/cache_arc700.c @@ -68,24 +68,14 @@ #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> - -#ifdef CONFIG_ARC_HAS_ICACHE -static void __ic_line_inv_no_alias(unsigned long, int); -static void __ic_line_inv_2_alias(unsigned long, int); -static void __ic_line_inv_4_alias(unsigned long, int); - -/* Holds the ptr to flush routine, dependign on size due to aliasing issues */ -static void (*___flush_icache_rtn) (unsigned long, int); -#endif - -char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len) +char *arc_cache_mumbojumbo(int c, char *buf, int len) { int n = 0; - unsigned int c = smp_processor_id(); #define PR_CACHE(p, enb, str) \ { \ @@ -98,8 +88,10 @@ char *arc_cache_mumbojumbo(int cpu_id, char *buf, int 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"); + PR_CACHE(&cpuinfo_arc700[c].icache, IS_ENABLED(CONFIG_ARC_HAS_ICACHE), + "I-Cache"); + PR_CACHE(&cpuinfo_arc700[c].dcache, IS_ENABLED(CONFIG_ARC_HAS_DCACHE), + "D-Cache"); return buf; } @@ -109,17 +101,23 @@ char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len) * the cpuinfo structure for later use. * No Validation done here, simply read/convert the BCRs */ -void __init read_decode_cache_bcr(void) +void read_decode_cache_bcr(void) { - struct bcr_cache ibcr, dbcr; struct cpuinfo_arc_cache *p_ic, *p_dc; unsigned int cpu = smp_processor_id(); + struct bcr_cache { +#ifdef CONFIG_CPU_BIG_ENDIAN + unsigned int pad:12, line_len:4, sz:4, config:4, ver:8; +#else + unsigned int ver:8, config:4, sz:4, line_len:4, pad:12; +#endif + } ibcr, dbcr; p_ic = &cpuinfo_arc700[cpu].icache; READ_BCR(ARC_REG_IC_BCR, ibcr); - if (ibcr.config == 0x3) - p_ic->assoc = 2; + BUG_ON(ibcr.config != 3); + p_ic->assoc = 2; /* Fixed to 2w set assoc */ p_ic->line_len = 8 << ibcr.line_len; p_ic->sz = 0x200 << ibcr.sz; p_ic->ver = ibcr.ver; @@ -127,8 +125,8 @@ void __init read_decode_cache_bcr(void) p_dc = &cpuinfo_arc700[cpu].dcache; READ_BCR(ARC_REG_DC_BCR, dbcr); - if (dbcr.config == 0x2) - p_dc->assoc = 4; + BUG_ON(dbcr.config != 2); + p_dc->assoc = 4; /* Fixed to 4w set assoc */ p_dc->line_len = 16 << dbcr.line_len; p_dc->sz = 0x200 << dbcr.sz; p_dc->ver = dbcr.ver; @@ -141,112 +139,116 @@ void __init read_decode_cache_bcr(void) * 3. Enable the Caches, setup default flush mode for D-Cache * 3. Calculate the SHMLBA used by user space */ -void __init arc_cache_init(void) +void 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; + unsigned int __maybe_unused cpu = smp_processor_id(); + struct cpuinfo_arc_cache __maybe_unused *ic, __maybe_unused *dc; 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"); - + ic = &cpuinfo_arc700[cpu].icache; + if (ic->ver) { + if (ic->line_len != L1_CACHE_BYTES) + panic("ICache line [%d] != kernel Config [%d]", + ic->line_len, L1_CACHE_BYTES); + + if (ic->ver != CONFIG_ARC_MMU_VER) + panic("Cache ver [%d] doesn't match MMU ver [%d]\n", + ic->ver, CONFIG_ARC_MMU_VER); } #endif - /* - * if Cache way size is <= page size then no aliasing exhibited - * otherwise ratio determines num of aliases. - * e.g. 32K I$, 2 way set assoc, 8k pg size - * way-sz = 32k/2 = 16k - * way-pg-ratio = 16k/8k = 2, so 2 aliases possible - * (meaning 1 line could be in 2 possible locations). - */ - way_pg_ratio = ic->sz / ARC_ICACHE_WAYS / PAGE_SIZE; - switch (way_pg_ratio) { - case 0: - case 1: - ___flush_icache_rtn = __ic_line_inv_no_alias; - break; - case 2: - ___flush_icache_rtn = __ic_line_inv_2_alias; - break; - case 4: - ___flush_icache_rtn = __ic_line_inv_4_alias; - break; - default: - panic("Unsupported I-Cache Sz\n"); - } -#endif +#ifdef CONFIG_ARC_HAS_DCACHE + dc = &cpuinfo_arc700[cpu].dcache; + if (dc->ver) { + unsigned int dcache_does_alias; - /* Enable/disable I-Cache */ - temp = read_aux_reg(ARC_REG_IC_CTRL); + if (dc->line_len != L1_CACHE_BYTES) + panic("DCache line [%d] != kernel Config [%d]", + dc->line_len, L1_CACHE_BYTES); -#ifdef CONFIG_ARC_HAS_ICACHE - temp &= ~IC_CTRL_CACHE_DISABLE; -#else - temp |= IC_CTRL_CACHE_DISABLE; + /* check for D-Cache aliasing */ + dcache_does_alias = (dc->sz / dc->assoc) > PAGE_SIZE; + + 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 +} - write_aux_reg(ARC_REG_IC_CTRL, temp); +#define OP_INV 0x1 +#define OP_FLUSH 0x2 +#define OP_FLUSH_N_INV 0x3 +#define OP_INV_IC 0x4 -chk_dc: - if (!dc->ver) - return; +/* + * Common Helper for Line Operations on {I,D}-Cache + */ +static inline void __cache_line_loop(unsigned long paddr, unsigned long vaddr, + unsigned long sz, const int cacheop) +{ + unsigned int aux_cmd, aux_tag; + int num_lines; + const int full_page_op = __builtin_constant_p(sz) && sz == PAGE_SIZE; -#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"); + if (cacheop == OP_INV_IC) { + aux_cmd = ARC_REG_IC_IVIL; +#if (CONFIG_ARC_MMU_VER > 2) + aux_tag = ARC_REG_IC_PTAG; +#endif } - - /* check for D-Cache aliasing */ - if ((dc->sz / ARC_DCACHE_WAYS) > PAGE_SIZE) - panic("D$ aliasing not handled right now\n"); + else { + /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */ + aux_cmd = cacheop & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL; +#if (CONFIG_ARC_MMU_VER > 2) + aux_tag = ARC_REG_DC_PTAG; #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 + /* 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). */ - temp = read_aux_reg(ARC_REG_DC_CTRL); - temp &= ~DC_CTRL_INV_MODE_FLUSH; + if (!full_page_op) { + sz += paddr & ~CACHE_LINE_MASK; + paddr &= CACHE_LINE_MASK; + vaddr &= CACHE_LINE_MASK; + } -#ifdef CONFIG_ARC_HAS_DCACHE - /* Enable D-Cache: Clear Bit 0 */ - write_aux_reg(ARC_REG_DC_CTRL, temp & ~IC_CTRL_CACHE_DISABLE); + num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES); + +#if (CONFIG_ARC_MMU_VER <= 2) + /* MMUv2 and before: paddr contains stuffed vaddrs bits */ + paddr |= (vaddr >> PAGE_SHIFT) & 0x1F; #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); + /* if V-P const for loop, PTAG can be written once outside loop */ + if (full_page_op) + write_aux_reg(aux_tag, paddr); #endif - return; + while (num_lines-- > 0) { +#if (CONFIG_ARC_MMU_VER > 2) + /* MMUv3, cache ops require paddr seperately */ + if (!full_page_op) { + write_aux_reg(aux_tag, paddr); + paddr += L1_CACHE_BYTES; + } + + write_aux_reg(aux_cmd, vaddr); + vaddr += L1_CACHE_BYTES; +#else + write_aux_reg(aux_cmd, paddr); + paddr += L1_CACHE_BYTES; +#endif + } } -#define OP_INV 0x1 -#define OP_FLUSH 0x2 -#define OP_FLUSH_N_INV 0x3 - #ifdef CONFIG_ARC_HAS_DCACHE /*************************************************************** @@ -267,11 +269,9 @@ static inline void wait_for_flush(void) */ static inline void __dc_entire_op(const int cacheop) { - unsigned long flags, tmp = tmp; + unsigned int 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 @@ -295,58 +295,18 @@ static inline void __dc_entire_op(const int cacheop) /* 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 - */ -static inline void __dc_line_loop(unsigned long start, unsigned long sz, - int aux_reg) -{ - int num_lines, slack; - - /* Ensure we properly floor/ceil the non-line aligned/sized requests - * and have @start - aligned to cache line and integral @num_lines. - * This however can be avoided for page sized since: - * -@start 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)) { - slack = start & ~DCACHE_LINE_MASK; - sz += slack; - start -= slack; - } - - num_lines = DIV_ROUND_UP(sz, ARC_DCACHE_LINE_LEN); - - 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 - * But we pass phy addr for both. This works since Linux - * doesn't support aliasing configs for D$, yet. - * Thus paddr is enough to provide both tag and index. - */ - write_aux_reg(ARC_REG_DC_PTAG, start); -#endif - write_aux_reg(aux_reg, start); - start += ARC_DCACHE_LINE_LEN; - } -} +/* For kernel mappings cache operation: index is same as paddr */ +#define __dc_line_op_k(p, sz, op) __dc_line_op(p, p, sz, op) /* * D-Cache : Per Line INV (discard or wback+discard) or FLUSH (wback) */ -static inline void __dc_line_op(unsigned long start, unsigned long sz, - const int cacheop) +static inline void __dc_line_op(unsigned long paddr, unsigned long vaddr, + unsigned long sz, const int cacheop) { unsigned long flags, tmp = tmp; - int aux; local_irq_save(flags); @@ -361,12 +321,7 @@ static inline void __dc_line_op(unsigned long start, unsigned long sz, write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH); } - if (cacheop & OP_INV) /* Inv / flush-n-inv use same cmd reg */ - aux = ARC_REG_DC_IVDL; - else - aux = ARC_REG_DC_FLDL; - - __dc_line_loop(start, sz, aux); + __cache_line_loop(paddr, vaddr, sz, cacheop); if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */ wait_for_flush(); @@ -381,7 +336,8 @@ static inline void __dc_line_op(unsigned long start, unsigned long sz, #else #define __dc_entire_op(cacheop) -#define __dc_line_op(start, sz, cacheop) +#define __dc_line_op(paddr, vaddr, sz, cacheop) +#define __dc_line_op_k(paddr, sz, cacheop) #endif /* CONFIG_ARC_HAS_DCACHE */ @@ -391,75 +347,38 @@ static inline void __dc_line_op(unsigned long start, unsigned long sz, /* * I-Cache Aliasing in ARC700 VIPT caches * - * For fetching code from I$, ARC700 uses vaddr (embedded in program code) - * to "index" into SET of cache-line and paddr from MMU to match the TAG - * in the WAYS of SET. - * - * However the CDU iterface (to flush/inv) lines from software, only takes - * paddr (to have simpler hardware interface). For simpler cases, using paddr - * alone suffices. - * e.g. 2-way-set-assoc, 16K I$ (8k MMU pg sz, 32b cache line size): - * way_sz = cache_sz / num_ways = 16k/2 = 8k - * num_sets = way_sz / line_sz = 8k/32 = 256 => 8 bits - * Ignoring the bottom 5 bits corresp to the off within a 32b cacheline, - * bits req for calc set-index = bits 12:5 (0 based). Since this range fits - * inside the bottom 13 bits of paddr, which are same for vaddr and paddr - * (with 8k pg sz), paddr alone can be safely used by CDU to unambigously - * locate a cache-line. + * 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 a difft sized cache, say 32k I$, above math yields need - * for 14 bits of vaddr to locate a cache line, which can't be provided by - * paddr, since the bit 13 (0 based) might differ between the two. - * - * This lack of extra bits needed for correct line addressing, defines the - * classical problem of Cache aliasing with VIPT architectures - * num_aliases = 1 << extra_bits - * e.g. 2-way-set-assoc, 32K I$ with 8k MMU pg sz => 2 aliases - * 2-way-set-assoc, 64K I$ with 8k MMU pg sz => 4 aliases - * 2-way-set-assoc, 16K I$ with 8k MMU pg sz => NO aliases + * 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-geom. + * 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. + * 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) * - * Since vaddr was not available for all instances of I$ flush req by core - * kernel, the only safe way (non-optimal though) was to kill all possible - * lines which could represent an alias (even if they didnt represent one - * in execution). - * e.g. for 64K I$, 4 aliases possible, so we did - * flush start - * flush start | 0x01 - * flush start | 0x2 - * flush start | 0x3 - * - * The penalty was invoking the operation itself, since tag match is anyways - * paddr based, a line which didn't represent an alias would not match the - * paddr, hence wont be killed - * - * Note that aliasing concerns are independent of line-sz for a given cache - * geometry (size + set_assoc) because the extra bits required by line-sz are - * reduced from the set calc. - * e.g. 2-way-set-assoc, 32K I$ with 8k MMU pg sz and using math above - * 32b line-sz: 9 bits set-index-calc, 5 bits offset-in-line => 1 extra bit - * 64b line-sz: 8 bits set-index-calc, 6 bits offset-in-line => 1 extra bit - * * ------------------ * MMU v3 * ------------------ - * This ver of MMU supports var page sizes (1k-16k) - Linux will support - * 8k (default), 16k and 4k. + * 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. @@ -468,144 +387,44 @@ static inline void __dc_line_op(unsigned long start, unsigned long sz, */ /*********************************************************** - * Machine specific helpers for per line I-Cache invalidate. - * 3 routines to accpunt for 1, 2, 4 aliases possible + * Machine specific helper for per line I-Cache invalidate. */ - -static void __ic_line_inv_no_alias(unsigned long start, int num_lines) -{ - while (num_lines-- > 0) { -#if (CONFIG_ARC_MMU_VER > 2) - write_aux_reg(ARC_REG_IC_PTAG, start); -#endif - write_aux_reg(ARC_REG_IC_IVIL, start); - start += ARC_ICACHE_LINE_LEN; - } -} - -static void __ic_line_inv_2_alias(unsigned long start, int num_lines) -{ - while (num_lines-- > 0) { - -#if (CONFIG_ARC_MMU_VER > 2) - /* - * MMU v3, CDU prog model (for line ops) now uses a new IC_PTAG - * reg to pass the "tag" bits and existing IVIL reg only looks - * at bits relevant for "index" (details above) - * Programming Notes: - * -when writing tag to PTAG reg, bit chopping can be avoided, - * CDU ignores non-tag bits. - * -Ideally "index" must be computed from vaddr, but it is not - * avail in these rtns. So to be safe, we kill the lines in all - * possible indexes corresp to num of aliases possible for - * given cache config. - */ - write_aux_reg(ARC_REG_IC_PTAG, start); - write_aux_reg(ARC_REG_IC_IVIL, - start & ~(0x1 << PAGE_SHIFT)); - write_aux_reg(ARC_REG_IC_IVIL, start | (0x1 << PAGE_SHIFT)); -#else - write_aux_reg(ARC_REG_IC_IVIL, start); - write_aux_reg(ARC_REG_IC_IVIL, start | 0x01); -#endif - start += ARC_ICACHE_LINE_LEN; - } -} - -static void __ic_line_inv_4_alias(unsigned long start, int num_lines) -{ - while (num_lines-- > 0) { - -#if (CONFIG_ARC_MMU_VER > 2) - write_aux_reg(ARC_REG_IC_PTAG, start); - - write_aux_reg(ARC_REG_IC_IVIL, - start & ~(0x3 << PAGE_SHIFT)); - write_aux_reg(ARC_REG_IC_IVIL, - start & ~(0x2 << PAGE_SHIFT)); - write_aux_reg(ARC_REG_IC_IVIL, - start & ~(0x1 << PAGE_SHIFT)); - write_aux_reg(ARC_REG_IC_IVIL, start | (0x3 << PAGE_SHIFT)); -#else - write_aux_reg(ARC_REG_IC_IVIL, start); - write_aux_reg(ARC_REG_IC_IVIL, start | 0x01); - write_aux_reg(ARC_REG_IC_IVIL, start | 0x02); - write_aux_reg(ARC_REG_IC_IVIL, start | 0x03); -#endif - start += ARC_ICACHE_LINE_LEN; - } -} - -static void __ic_line_inv(unsigned long start, unsigned long sz) +static void __ic_line_inv_vaddr_local(unsigned long paddr, unsigned long vaddr, + unsigned long sz) { unsigned long flags; - int num_lines, slack; - - /* - * Ensure we properly floor/ceil the non-line aligned/sized requests - * and have @start - aligned to cache line, and integral @num_lines - * However page sized flushes can be compile time optimised. - * -@start 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)) { - slack = start & ~ICACHE_LINE_MASK; - sz += slack; - start -= slack; - } - - num_lines = DIV_ROUND_UP(sz, ARC_ICACHE_LINE_LEN); local_irq_save(flags); - (*___flush_icache_rtn) (start, num_lines); + __cache_line_loop(paddr, vaddr, sz, OP_INV_IC); local_irq_restore(flags); } -/* Unlike routines above, having vaddr for flush op (along with paddr), - * prevents the need to speculatively kill the lines in multiple sets - * based on ratio of way_sz : pg_sz - */ -static void __ic_line_inv_vaddr(unsigned long phy_start, - unsigned long vaddr, unsigned long sz) +static inline void __ic_entire_inv(void) { - unsigned long flags; - int num_lines, slack; - unsigned int addr; - - slack = phy_start & ~ICACHE_LINE_MASK; - sz += slack; - phy_start -= slack; - num_lines = DIV_ROUND_UP(sz, ARC_ICACHE_LINE_LEN); - -#if (CONFIG_ARC_MMU_VER > 2) - vaddr &= ~ICACHE_LINE_MASK; - addr = phy_start; -#else - /* bits 17:13 of vaddr go as bits 4:0 of paddr */ - addr = phy_start | ((vaddr >> 13) & 0x1F); -#endif + write_aux_reg(ARC_REG_IC_IVIC, 1); + read_aux_reg(ARC_REG_IC_CTRL); /* blocks */ +} - 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, addr); +struct ic_line_inv_vaddr_ipi { + unsigned long paddr, vaddr; + int sz; +}; - /* index bits come from vaddr */ - write_aux_reg(ARC_REG_IC_IVIL, vaddr); - vaddr += ARC_ICACHE_LINE_LEN; -#else - /* this paddr contains vaddrs bits as needed */ - write_aux_reg(ARC_REG_IC_IVIL, addr); -#endif - addr += ARC_ICACHE_LINE_LEN; - } - local_irq_restore(flags); +static void __ic_line_inv_vaddr_helper(void *info) +{ + struct ic_line_inv_vaddr_ipi *ic_inv = (struct ic_line_inv_vaddr_ipi*) info; + __ic_line_inv_vaddr_local(ic_inv->paddr, ic_inv->vaddr, ic_inv->sz); } +static void __ic_line_inv_vaddr(unsigned long paddr, unsigned long vaddr, + unsigned long sz) +{ + struct ic_line_inv_vaddr_ipi ic_inv = { paddr, vaddr , sz}; + on_each_cpu(__ic_line_inv_vaddr_helper, &ic_inv, 1); +} #else -#define __ic_line_inv(start, sz) +#define __ic_entire_inv() #define __ic_line_inv_vaddr(pstart, vstart, sz) #endif /* CONFIG_ARC_HAS_ICACHE */ @@ -615,35 +434,72 @@ static void __ic_line_inv_vaddr(unsigned long phy_start, * Exported APIs */ -/* TBD: use pg_arch_1 to optimize this */ +/* + * 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) { - __dc_line_op((unsigned long)page_address(page), PAGE_SIZE, OP_FLUSH); + struct address_space *mapping; + + if (!cache_is_vipt_aliasing()) { + clear_bit(PG_dc_clean, &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)) { + clear_bit(PG_dc_clean, &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(start, sz, OP_FLUSH_N_INV); + __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(start, sz, OP_INV); + __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(start, sz, OP_FLUSH); + __dc_line_op_k(start, sz, OP_FLUSH); } EXPORT_SYMBOL(dma_cache_wback); /* - * This is API for making I/D Caches consistent when modifying code - * (loadable modules, kprobes, etc) + * 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 @@ -652,7 +508,6 @@ void flush_icache_range(unsigned long kstart, unsigned long kend) { unsigned int tot_sz, off, sz; unsigned long phy, pfn; - unsigned long flags; /* printk("Kernel Cache Cohenercy: %lx to %lx\n",kstart, kend); */ @@ -673,8 +528,13 @@ void flush_icache_range(unsigned long kstart, unsigned long kend) /* Case: Kernel Phy addr (0x8000_0000 onwards) */ if (likely(kstart > PAGE_OFFSET)) { - __ic_line_inv(kstart, kend - kstart); - __dc_line_op(kstart, kend - kstart, OP_FLUSH); + /* + * 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; } @@ -692,70 +552,144 @@ void flush_icache_range(unsigned long kstart, unsigned long kend) pfn = vmalloc_to_pfn((void *)kstart); phy = (pfn << PAGE_SHIFT) + off; sz = min_t(unsigned int, tot_sz, PAGE_SIZE - off); - local_irq_save(flags); - __dc_line_op(phy, sz, OP_FLUSH); - __ic_line_inv(phy, sz); - local_irq_restore(flags); + __sync_icache_dcache(phy, kstart, sz); kstart += sz; tot_sz -= sz; } } /* - * Optimised ver of flush_icache_range() with spec callers: ptrace/signals - * where vaddr is also available. This allows passing both vaddr and paddr - * bits to CDU for cache flush, short-circuting the current pessimistic algo - * which kills all possible aliases. - * An added adv of knowing that vaddr is user-vaddr avoids various checks - * and handling for k-vaddr, k-paddr as done in orig ver above + * General purpose helper to make I and D cache lines consistent. + * @paddr is phy addr of region + * @vaddr is typically user vaddr (breakpoint) or kernel vaddr (vmalloc) + * However in one instance, when called 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 + * builtin kernel page will not have any virtual mappings. + * kprobe on loadable module will be kernel vaddr. */ -void flush_icache_range_vaddr(unsigned long paddr, unsigned long u_vaddr, - int len) +void __sync_icache_dcache(unsigned long paddr, unsigned long vaddr, int len) { - __ic_line_inv_vaddr(paddr, u_vaddr, len); - __dc_line_op(paddr, len, OP_FLUSH); + __dc_line_op(paddr, vaddr, len, OP_FLUSH_N_INV); + __ic_line_inv_vaddr(paddr, vaddr, len); +} + +/* 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); } /* - * XXX: This also needs to be optim using pg_arch_1 - * This is called when a page-cache page is about to be mapped into a - * user process' address space. It offers an opportunity for a - * port to ensure d-cache/i-cache coherency if necessary. + * wrapper to clearout kernel or userspace mappings of a page + * For kernel mappings @vaddr == @paddr */ -void flush_icache_page(struct vm_area_struct *vma, struct page *page) +void ___flush_dcache_page(unsigned long paddr, unsigned long vaddr) { - if (!(vma->vm_flags & VM_EXEC)) - return; - - __ic_line_inv((unsigned long)page_address(page), PAGE_SIZE); + __dc_line_op(paddr, vaddr & PAGE_MASK, PAGE_SIZE, OP_FLUSH_N_INV); } -void flush_icache_all(void) +noinline void flush_cache_all(void) { unsigned long flags; local_irq_save(flags); - write_aux_reg(ARC_REG_IC_IVIC, 1); + __ic_entire_inv(); + __dc_entire_op(OP_FLUSH_N_INV); - /* 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) +#ifdef CONFIG_ARC_CACHE_VIPT_ALIASING + +void flush_cache_mm(struct mm_struct *mm) { - unsigned long flags; + flush_cache_all(); +} - local_irq_save(flags); +void flush_cache_page(struct vm_area_struct *vma, unsigned long u_vaddr, + unsigned long pfn) +{ + unsigned int paddr = pfn << PAGE_SHIFT; - flush_icache_all(); - __dc_entire_op(OP_FLUSH_N_INV); + u_vaddr &= PAGE_MASK; - local_irq_restore(flags); + ___flush_dcache_page(paddr, u_vaddr); + + if (vma->vm_flags & VM_EXEC) + __inv_icache_page(paddr, u_vaddr); +} + +void flush_cache_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + flush_cache_all(); +} + +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 + +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). + */ + clear_bit(PG_dc_clean, &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); + set_bit(PG_dc_clean, &from->flags); + } else { + clear_bit(PG_dc_clean, &from->flags); + } +} + +void clear_user_page(void *to, unsigned long u_vaddr, struct page *page) +{ + clear_page(to); + clear_bit(PG_dc_clean, &page->flags); +} + + /********************************************************************** * Explicit Cache flush request from user space via syscall * Needed for JITs which generate code on the fly |