summaryrefslogtreecommitdiff
path: root/arch/arc/mm/cache.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arc/mm/cache.c')
-rw-r--r--arch/arc/mm/cache.c641
1 files changed, 267 insertions, 374 deletions
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index a867575a758b..7d2f93dc1e91 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* ARC Cache Management
*
* Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
* 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.
*/
#include <linux/module.h>
@@ -31,6 +28,10 @@ int slc_enable = 1, ioc_enable = 1;
unsigned long perip_base = ARC_UNCACHED_ADDR_SPACE; /* legacy value for boot */
unsigned long perip_end = 0xFFFFFFFF; /* legacy value */
+static struct cpuinfo_arc_cache {
+ unsigned int sz_k, line_len, colors;
+} ic_info, dc_info, slc_info;
+
void (*_cache_line_loop_ic_fn)(phys_addr_t paddr, unsigned long vaddr,
unsigned long sz, const int op, const int full_page);
@@ -38,150 +39,122 @@ void (*__dma_cache_wback_inv)(phys_addr_t start, unsigned long sz);
void (*__dma_cache_inv)(phys_addr_t start, unsigned long sz);
void (*__dma_cache_wback)(phys_addr_t start, unsigned long sz);
-char *arc_cache_mumbojumbo(int c, char *buf, int len)
-{
- int n = 0;
- struct cpuinfo_arc_cache *p;
-
-#define PR_CACHE(p, cfg, str) \
- if (!(p)->line_len) \
- n += scnprintf(buf + n, len - n, str"\t\t: N/A\n"); \
- else \
- n += scnprintf(buf + n, len - n, \
- str"\t\t: %uK, %dway/set, %uB Line, %s%s%s\n", \
- (p)->sz_k, (p)->assoc, (p)->line_len, \
- (p)->vipt ? "VIPT" : "PIPT", \
- (p)->alias ? " aliasing" : "", \
- IS_USED_CFG(cfg));
-
- PR_CACHE(&cpuinfo_arc700[c].icache, CONFIG_ARC_HAS_ICACHE, "I-Cache");
- PR_CACHE(&cpuinfo_arc700[c].dcache, CONFIG_ARC_HAS_DCACHE, "D-Cache");
-
- p = &cpuinfo_arc700[c].slc;
- if (p->line_len)
- n += scnprintf(buf + n, len - n,
- "SLC\t\t: %uK, %uB Line%s\n",
- p->sz_k, p->line_len, IS_USED_RUN(slc_enable));
-
- n += scnprintf(buf + n, len - n, "Peripherals\t: %#lx%s%s\n",
- perip_base,
- IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency "));
-
- 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
- */
-static void read_decode_cache_bcr_arcv2(int cpu)
+static int read_decode_cache_bcr_arcv2(int c, char *buf, int len)
{
- struct cpuinfo_arc_cache *p_slc = &cpuinfo_arc700[cpu].slc;
+ struct cpuinfo_arc_cache *p_slc = &slc_info;
+ struct bcr_identity ident;
struct bcr_generic sbcr;
-
- struct bcr_slc_cfg {
-#ifdef CONFIG_CPU_BIG_ENDIAN
- unsigned int pad:24, way:2, lsz:2, sz:4;
-#else
- unsigned int sz:4, lsz:2, way:2, pad:24;
-#endif
- } slc_cfg;
-
- struct bcr_clust_cfg {
-#ifdef CONFIG_CPU_BIG_ENDIAN
- unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
-#else
- unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
-#endif
- } cbcr;
-
- struct bcr_volatile {
-#ifdef CONFIG_CPU_BIG_ENDIAN
- unsigned int start:4, limit:4, pad:22, order:1, disable:1;
-#else
- unsigned int disable:1, order:1, pad:22, limit:4, start:4;
-#endif
- } vol;
-
+ struct bcr_clust_cfg cbcr;
+ struct bcr_volatile vol;
+ int n = 0;
READ_BCR(ARC_REG_SLC_BCR, sbcr);
if (sbcr.ver) {
+ struct bcr_slc_cfg slc_cfg;
READ_BCR(ARC_REG_SLC_CFG, slc_cfg);
p_slc->sz_k = 128 << slc_cfg.sz;
l2_line_sz = p_slc->line_len = (slc_cfg.lsz == 0) ? 128 : 64;
+ n += scnprintf(buf + n, len - n,
+ "SLC\t\t: %uK, %uB Line%s\n",
+ p_slc->sz_k, p_slc->line_len, IS_USED_RUN(slc_enable));
}
READ_BCR(ARC_REG_CLUSTER_BCR, cbcr);
- if (cbcr.c)
+ if (cbcr.c) {
ioc_exists = 1;
- else
+
+ /*
+ * 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) || is_pae40_enabled())
+ ioc_enable = 0;
+ } else {
ioc_enable = 0;
+ }
+
+ READ_BCR(AUX_IDENTITY, ident);
/* HS 2.0 didn't have AUX_VOL */
- if (cpuinfo_arc700[cpu].core.family > 0x51) {
+ if (ident.family > 0x51) {
READ_BCR(AUX_VOL, vol);
perip_base = vol.start << 28;
/* HS 3.0 has limit and strict-ordering fields */
- if (cpuinfo_arc700[cpu].core.family > 0x52)
+ if (ident.family > 0x52)
perip_end = (vol.limit << 28) - 1;
}
+
+ n += scnprintf(buf + n, len - n, "Peripherals\t: %#lx%s%s\n",
+ perip_base,
+ IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency (per-device) "));
+
+ return n;
}
-void read_decode_cache_bcr(void)
+int arc_cache_mumbojumbo(int c, char *buf, int len)
{
- 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;
+ struct cpuinfo_arc_cache *p_ic = &ic_info, *p_dc = &dc_info;
+ struct bcr_cache ibcr, dbcr;
+ int vipt, assoc;
+ int n = 0;
- p_ic = &cpuinfo_arc700[cpu].icache;
READ_BCR(ARC_REG_IC_BCR, ibcr);
-
if (!ibcr.ver)
goto dc_chk;
- if (ibcr.ver <= 3) {
+ if (is_isa_arcompact() && (ibcr.ver <= 3)) {
BUG_ON(ibcr.config != 3);
- p_ic->assoc = 2; /* Fixed to 2w set assoc */
- } else if (ibcr.ver >= 4) {
- p_ic->assoc = 1 << ibcr.config; /* 1,2,4,8 */
+ assoc = 2; /* Fixed to 2w set assoc */
+ } else if (is_isa_arcv2() && (ibcr.ver >= 4)) {
+ assoc = 1 << ibcr.config; /* 1,2,4,8 */
}
p_ic->line_len = 8 << ibcr.line_len;
p_ic->sz_k = 1 << (ibcr.sz - 1);
- p_ic->vipt = 1;
- p_ic->alias = p_ic->sz_k/p_ic->assoc/TO_KB(PAGE_SIZE) > 1;
+ p_ic->colors = p_ic->sz_k/assoc/TO_KB(PAGE_SIZE);
+
+ n += scnprintf(buf + n, len - n,
+ "I-Cache\t\t: %uK, %dway/set, %uB Line, VIPT%s%s\n",
+ p_ic->sz_k, assoc, p_ic->line_len,
+ p_ic->colors > 1 ? " aliasing" : "",
+ IS_USED_CFG(CONFIG_ARC_HAS_ICACHE));
dc_chk:
- p_dc = &cpuinfo_arc700[cpu].dcache;
READ_BCR(ARC_REG_DC_BCR, dbcr);
-
if (!dbcr.ver)
goto slc_chk;
- if (dbcr.ver <= 3) {
+ if (is_isa_arcompact() && (dbcr.ver <= 3)) {
BUG_ON(dbcr.config != 2);
- p_dc->assoc = 4; /* Fixed to 4w set assoc */
- p_dc->vipt = 1;
- p_dc->alias = p_dc->sz_k/p_dc->assoc/TO_KB(PAGE_SIZE) > 1;
- } else if (dbcr.ver >= 4) {
- p_dc->assoc = 1 << dbcr.config; /* 1,2,4,8 */
- p_dc->vipt = 0;
- p_dc->alias = 0; /* PIPT so can't VIPT alias */
+ vipt = 1;
+ assoc = 4; /* Fixed to 4w set assoc */
+ p_dc->colors = p_dc->sz_k/assoc/TO_KB(PAGE_SIZE);
+ } else if (is_isa_arcv2() && (dbcr.ver >= 4)) {
+ vipt = 0;
+ assoc = 1 << dbcr.config; /* 1,2,4,8 */
+ p_dc->colors = 1; /* PIPT so can't VIPT alias */
}
p_dc->line_len = 16 << dbcr.line_len;
p_dc->sz_k = 1 << (dbcr.sz - 1);
+ n += scnprintf(buf + n, len - n,
+ "D-Cache\t\t: %uK, %dway/set, %uB Line, %s%s\n",
+ p_dc->sz_k, assoc, p_dc->line_len,
+ vipt ? "VIPT" : "PIPT",
+ IS_USED_CFG(CONFIG_ARC_HAS_DCACHE));
+
slc_chk:
if (is_isa_arcv2())
- read_decode_cache_bcr_arcv2(cpu);
+ n += read_decode_cache_bcr_arcv2(c, buf + n, len - n);
+
+ return n;
}
/*
@@ -194,93 +167,24 @@ slc_chk:
#define OP_INV_IC 0x4
/*
- * I-Cache Aliasing in ARC700 VIPT caches (MMU v1-v3)
+ * Cache Flush programming model
*
- * 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.
+ * ARC700 MMUv3 I$ and D$ are both VIPT and can potentially alias.
+ * Programming model requires both paddr and vaddr irrespecive of aliasing
+ * considerations:
+ * - vaddr in {I,D}C_IV?L
+ * - paddr in {I,D}C_PTAG
*
- * However for larger Caches (way-size > page-size) - i.e. in Aliasing config,
- * paddr alone could not be used to correctly index the cache.
+ * In HS38x (MMUv4), D$ is PIPT, I$ is VIPT and can still alias.
+ * Programming model is different for aliasing vs. non-aliasing I$
+ * - D$ / Non-aliasing I$: only paddr in {I,D}C_IV?L
+ * - Aliasing I$: same as ARC700 above (so MMUv3 routine used for MMUv4 I$)
*
- * ------------------
- * MMU v1/v2 (Fixed Page Size 8k)
- * ------------------
- * The solution was to provide CDU with these additonal vaddr bits. These
- * would be bits [x:13], x would depend on cache-geometry, 13 comes from
- * standard page size of 8k.
- * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits
- * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the
- * orig 5 bits of paddr were anyways ignored by CDU line ops, as they
- * represent the offset within cache-line. The adv of using this "clumsy"
- * interface for additional info was no new reg was needed in CDU programming
- * model.
- *
- * 17:13 represented the max num of bits passable, actual bits needed were
- * fewer, based on the num-of-aliases possible.
- * -for 2 alias possibility, only bit 13 needed (32K cache)
- * -for 4 alias possibility, bits 14:13 needed (64K cache)
- *
- * ------------------
- * MMU v3
- * ------------------
- * This ver of MMU supports variable page sizes (1k-16k): although Linux will
- * only support 8k (default), 16k and 4k.
- * However from hardware perspective, smaller page sizes aggravate aliasing
- * meaning more vaddr bits needed to disambiguate the cache-line-op ;
- * the existing scheme of piggybacking won't work for certain configurations.
- * Two new registers IC_PTAG and DC_PTAG inttoduced.
- * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs
+ * - If PAE40 is enabled, independent of aliasing considerations, the higher
+ * bits needs to be written into PTAG_HI
*/
static inline
-void __cache_line_loop_v2(phys_addr_t paddr, unsigned long vaddr,
- unsigned long sz, const int op, const int full_page)
-{
- unsigned int aux_cmd;
- int num_lines;
-
- if (op == OP_INV_IC) {
- aux_cmd = ARC_REG_IC_IVIL;
- } else {
- /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
- aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
- }
-
- /* 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 (!full_page) {
- sz += paddr & ~CACHE_LINE_MASK;
- paddr &= CACHE_LINE_MASK;
- vaddr &= CACHE_LINE_MASK;
- }
-
- num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
-
- /* MMUv2 and before: paddr contains stuffed vaddrs bits */
- paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
-
- while (num_lines-- > 0) {
- write_aux_reg(aux_cmd, paddr);
- paddr += L1_CACHE_BYTES;
- }
-}
-
-/*
- * For ARC700 MMUv3 I-cache and D-cache flushes
- * - ARC700 programming model requires paddr and vaddr be passed in seperate
- * AUX registers (*_IV*L and *_PTAG respectively) irrespective of whether the
- * caches actually alias or not.
- * - For HS38, only the aliasing I-cache configuration uses the PTAG reg
- * (non aliasing I-cache version doesn't; while D-cache can't possibly alias)
- */
-static inline
void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
unsigned long sz, const int op, const int full_page)
{
@@ -339,17 +243,6 @@ void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
#ifndef USE_RGN_FLSH
/*
- * In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
- * Here's how cache ops are implemented
- *
- * - D-cache: only paddr needed (in DC_IVDL/DC_FLDL)
- * - I-cache Non Aliasing: Despite VIPT, only paddr needed (in IC_IVIL)
- * - I-cache Aliasing: Both vaddr and paddr needed (in IC_IVIL, IC_PTAG
- * respectively, similar to MMU v3 programming model, hence
- * __cache_line_loop_v3() is used)
- *
- * If PAE40 is enabled, independent of aliasing considerations, the higher bits
- * needs to be written into PTAG_HI
*/
static inline
void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
@@ -449,11 +342,9 @@ void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
#endif
-#if (CONFIG_ARC_MMU_VER < 3)
-#define __cache_line_loop __cache_line_loop_v2
-#elif (CONFIG_ARC_MMU_VER == 3)
+#ifdef CONFIG_ARC_MMU_V3
#define __cache_line_loop __cache_line_loop_v3
-#elif (CONFIG_ARC_MMU_VER > 3)
+#else
#define __cache_line_loop __cache_line_loop_v4
#endif
@@ -472,7 +363,7 @@ static inline void __before_dc_op(const int op)
{
if (op == OP_FLUSH_N_INV) {
/* Dcache provides 2 cmd: FLUSH or INV
- * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE
+ * INV in turn has sub-modes: DISCARD or FLUSH-BEFORE
* flush-n-inv is achieved by INV cmd but with IM=1
* So toggle INV sub-mode depending on op request and default
*/
@@ -652,7 +543,7 @@ static void __ic_line_inv_vaddr(phys_addr_t paddr, unsigned long vaddr,
#endif /* CONFIG_ARC_HAS_ICACHE */
-noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
+static noinline void slc_op_rgn(phys_addr_t paddr, unsigned long sz, const int op)
{
#ifdef CONFIG_ISA_ARCV2
/*
@@ -665,6 +556,7 @@ 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 +586,19 @@ 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);
@@ -703,6 +606,58 @@ noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
#endif
}
+static __maybe_unused noinline void slc_op_line(phys_addr_t paddr, unsigned long sz, const int op)
+{
+#ifdef CONFIG_ISA_ARCV2
+ /*
+ * SLC is shared between all cores and concurrent aux operations from
+ * multiple cores need to be serialized using a spinlock
+ * A concurrent operation can be silently ignored and/or the old/new
+ * operation can remain incomplete forever (lockup in SLC_CTRL_BUSY loop
+ * below)
+ */
+ static DEFINE_SPINLOCK(lock);
+
+ const unsigned long SLC_LINE_MASK = ~(l2_line_sz - 1);
+ unsigned int ctrl, cmd;
+ unsigned long flags;
+ int num_lines;
+
+ spin_lock_irqsave(&lock, flags);
+
+ ctrl = read_aux_reg(ARC_REG_SLC_CTRL);
+
+ /* Don't rely on default value of IM bit */
+ if (!(op & OP_FLUSH)) /* i.e. OP_INV */
+ ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
+ else
+ ctrl |= SLC_CTRL_IM;
+
+ write_aux_reg(ARC_REG_SLC_CTRL, ctrl);
+
+ cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
+
+ sz += paddr & ~SLC_LINE_MASK;
+ paddr &= SLC_LINE_MASK;
+
+ num_lines = DIV_ROUND_UP(sz, l2_line_sz);
+
+ while (num_lines-- > 0) {
+ write_aux_reg(cmd, paddr);
+ paddr += l2_line_sz;
+ }
+
+ /* 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);
+
+ spin_unlock_irqrestore(&lock, flags);
+#endif
+}
+
+#define slc_op(paddr, sz, op) slc_op_rgn(paddr, sz, op)
+
noinline static void slc_entire_op(const int op)
{
unsigned int ctrl, r = ARC_REG_SLC_CTRL;
@@ -716,7 +671,10 @@ noinline static void slc_entire_op(const int op)
write_aux_reg(r, ctrl);
- write_aux_reg(ARC_REG_SLC_INVALIDATE, 1);
+ if (op & OP_INV) /* Inv or flush-n-inv use same cmd reg */
+ write_aux_reg(ARC_REG_SLC_INVALIDATE, 0x1);
+ else
+ write_aux_reg(ARC_REG_SLC_FLUSH, 0x1);
/* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
read_aux_reg(r);
@@ -744,47 +702,16 @@ static inline void arc_slc_enable(void)
* 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)
+void flush_dcache_folio(struct folio *folio)
{
- 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_mapcount(page)) {
-
- /* kernel reading from page with U-mapping */
- phys_addr_t paddr = (unsigned long)page_address(page);
- unsigned long vaddr = page->index << PAGE_SHIFT;
+ clear_bit(PG_dc_clean, &folio->flags.f);
+ return;
+}
+EXPORT_SYMBOL(flush_dcache_folio);
- if (addr_not_cache_congruent(paddr, vaddr))
- __flush_dcache_page(paddr, vaddr);
- }
+void flush_dcache_page(struct page *page)
+{
+ return flush_dcache_folio(page_folio(page));
}
EXPORT_SYMBOL(flush_dcache_page);
@@ -830,15 +757,6 @@ 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)
@@ -923,7 +841,7 @@ EXPORT_SYMBOL(flush_icache_range);
* @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
+ * use a paddr to index the cache (despite VIPT). This is fine since a
* builtin kernel page will not have any virtual mappings.
* kprobe on loadable module will be kernel vaddr.
*/
@@ -934,18 +852,18 @@ void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len)
}
/* wrapper to compile time eliminate alignment checks in flush loop */
-void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr)
+void __inv_icache_pages(phys_addr_t paddr, unsigned long vaddr, unsigned nr)
{
- __ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE);
+ __ic_line_inv_vaddr(paddr, vaddr, nr * PAGE_SIZE);
}
/*
* wrapper to clearout kernel or userspace mappings of a page
* For kernel mappings @vaddr == @paddr
*/
-void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr)
+void __flush_dcache_pages(phys_addr_t paddr, unsigned long vaddr, unsigned nr)
{
- __dc_line_op(paddr, vaddr & PAGE_MASK, PAGE_SIZE, OP_FLUSH_N_INV);
+ __dc_line_op(paddr, vaddr & PAGE_MASK, nr * PAGE_SIZE, OP_FLUSH_N_INV);
}
noinline void flush_cache_all(void)
@@ -961,88 +879,18 @@ noinline void flush_cache_all(void)
}
-#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;
-
- u_vaddr &= PAGE_MASK;
-
- __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)
{
+ struct folio *src = page_folio(from);
+ struct folio *dst = page_folio(to);
void *kfrom = kmap_atomic(from);
void *kto = kmap_atomic(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
- *
- * For !VIPT cache, all of this gets compiled out as
- * addr_not_cache_congruent() is 0
- */
- if (page_mapcount(from) && addr_not_cache_congruent(kfrom, u_vaddr)) {
- __flush_dcache_page((unsigned long)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((unsigned long)kfrom, (unsigned long)kfrom);
- set_bit(PG_dc_clean, &from->flags);
- } else {
- clear_bit(PG_dc_clean, &from->flags);
- }
+ clear_bit(PG_dc_clean, &dst->flags.f);
+ clear_bit(PG_dc_clean, &src->flags.f);
kunmap_atomic(kto);
kunmap_atomic(kfrom);
@@ -1050,10 +898,11 @@ void copy_user_highpage(struct page *to, struct page *from,
void clear_user_page(void *to, unsigned long u_vaddr, struct page *page)
{
+ struct folio *folio = page_folio(page);
clear_page(to);
- clear_bit(PG_dc_clean, &page->flags);
+ clear_bit(PG_dc_clean, &folio->flags.f);
}
-
+EXPORT_SYMBOL(clear_user_page);
/**********************************************************************
* Explicit Cache flush request from user space via syscall
@@ -1081,9 +930,23 @@ SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags)
* 3. All Caches need to be disabled when setting up IOC to elide any in-flight
* Coherency transactions
*/
-noinline void __init arc_ioc_setup(void)
+static noinline void __init arc_ioc_setup(void)
{
- unsigned int ap_sz;
+ unsigned int ioc_base, mem_sz;
+
+ /*
+ * If IOC was already enabled (due to bootloader) it technically needs to
+ * be reconfigured with aperture base,size corresponding to Linux memory map
+ * which will certainly be different than uboot's. But disabling and
+ * reenabling IOC when DMA might be potentially active is tricky business.
+ * To avoid random memory issues later, just panic here and ask user to
+ * upgrade bootloader to one which doesn't enable IOC
+ */
+ if (read_aux_reg(ARC_REG_IO_COH_ENABLE) & ARC_IO_COH_ENABLE_BIT)
+ panic("IOC already enabled, please upgrade bootloader!\n");
+
+ if (!ioc_enable)
+ return;
/* Flush + invalidate + disable L1 dcache */
__dc_disable();
@@ -1092,31 +955,47 @@ noinline void __init arc_ioc_setup(void)
if (read_aux_reg(ARC_REG_SLC_BCR))
slc_entire_op(OP_FLUSH_N_INV);
- /* IOC Aperture start: TDB: handle non default CONFIG_LINUX_LINK_BASE */
- write_aux_reg(ARC_REG_IO_COH_AP0_BASE, 0x80000);
-
/*
- * IOC Aperture size:
- * decoded as 2 ^ (SIZE + 2) KB: so setting 0x11 implies 512M
+ * currently IOC Aperture covers entire DDR
* TBD: fix for PGU + 1GB of low mem
* TBD: fix for PAE
*/
- ap_sz = order_base_2(arc_get_mem_sz()/1024) - 2;
- write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, ap_sz);
+ mem_sz = arc_get_mem_sz();
+
+ if (!is_power_of_2(mem_sz) || mem_sz < 4096)
+ panic("IOC Aperture size must be power of 2 larger than 4KB");
+
+ /*
+ * IOC Aperture size decoded as 2 ^ (SIZE + 2) KB,
+ * so setting 0x11 implies 512MB, 0x12 implies 1GB...
+ */
+ write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, order_base_2(mem_sz >> 10) - 2);
- write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
- write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);
+ /* for now assume kernel base is start of IOC aperture */
+ ioc_base = CONFIG_LINUX_RAM_BASE;
+
+ if (ioc_base % mem_sz != 0)
+ panic("IOC Aperture start must be aligned to the size of the aperture");
+
+ write_aux_reg(ARC_REG_IO_COH_AP0_BASE, ioc_base >> 12);
+ write_aux_reg(ARC_REG_IO_COH_PARTIAL, ARC_IO_COH_PARTIAL_BIT);
+ write_aux_reg(ARC_REG_IO_COH_ENABLE, ARC_IO_COH_ENABLE_BIT);
/* Re-enable L1 dcache */
__dc_enable();
}
-void __init arc_cache_init_master(void)
+/*
+ * 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
+ */
+static noinline void __init arc_cache_init_master(void)
{
- unsigned int __maybe_unused cpu = smp_processor_id();
-
if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
- struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;
+ struct cpuinfo_arc_cache *ic = &ic_info;
if (!ic->line_len)
panic("cache support enabled but non-existent cache\n");
@@ -1129,14 +1008,14 @@ void __init arc_cache_init_master(void)
* In MMU v4 (HS38x) the aliasing icache config uses IVIL/PTAG
* pair to provide vaddr/paddr respectively, just as in MMU v3
*/
- if (is_isa_arcv2() && ic->alias)
+ if (is_isa_arcv2() && ic->colors > 1)
_cache_line_loop_ic_fn = __cache_line_loop_v3;
else
_cache_line_loop_ic_fn = __cache_line_loop;
}
if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE)) {
- struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache;
+ struct cpuinfo_arc_cache *dc = &dc_info;
if (!dc->line_len)
panic("cache support enabled but non-existent cache\n");
@@ -1146,33 +1025,29 @@ void __init arc_cache_init_master(void)
dc->line_len, L1_CACHE_BYTES);
/* check for D-Cache aliasing on ARCompact: ARCv2 has PIPT */
- if (is_isa_arcompact()) {
- int handled = IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
- int num_colors = dc->sz_k/dc->assoc/TO_KB(PAGE_SIZE);
-
- if (dc->alias) {
- if (!handled)
- panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
- if (CACHE_COLORS_NUM != num_colors)
- panic("CACHE_COLORS_NUM not optimized for config\n");
- } else if (!dc->alias && handled) {
- panic("Disable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
- }
+ if (is_isa_arcompact() && dc->colors > 1) {
+ panic("Aliasing VIPT cache not supported\n");
}
}
+ /*
+ * 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();
- if (is_isa_arcv2() && ioc_enable)
+ if (is_isa_arcv2() && ioc_exists)
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;
@@ -1181,21 +1056,39 @@ 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 devices using coherent DMA.
+ * arch_sync_dma_for_cpu() -> dma_cache_*() -> __dma_cache_*()
+ */
}
void __ref arc_cache_init(void)
{
unsigned int __maybe_unused cpu = smp_processor_id();
- char str[256];
- printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
+ if (!cpu)
+ arc_cache_init_master();
/*
- * 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
+ * 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 (!cpu)
- arc_cache_init_master();
+ 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);
+ }
+ }
}