From patchwork Mon Feb 23 18:28:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 5867721 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4B108BF440 for ; Mon, 23 Feb 2015 18:32:40 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 0A45020634 for ; Mon, 23 Feb 2015 18:32:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E9BB42062A for ; Mon, 23 Feb 2015 18:32:36 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YPxkH-0004hu-Nl; Mon, 23 Feb 2015 18:28:41 +0000 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YPxkC-0004fu-WA for linux-arm-kernel@lists.infradead.org; Mon, 23 Feb 2015 18:28:38 +0000 Received: from foss-smtp-na-1.foss.arm.com (unknown [10.80.61.8]) by foss-mx-na.foss.arm.com (Postfix) with ESMTP id 5AEBF25B; Mon, 23 Feb 2015 12:28:06 -0600 (CST) Received: from collaborate-mta1.arm.com (highbank-bc01-b06.austin.arm.com [10.112.81.134]) by foss-smtp-na-1.foss.arm.com (Postfix) with ESMTP id 30EE75FAC1; Mon, 23 Feb 2015 12:28:04 -0600 (CST) Received: from e103737-lin.cambridge.arm.com (e103737-lin.cambridge.arm.com [10.1.207.150]) by collaborate-mta1.arm.com (Postfix) with ESMTP id 4D61013F6D0; Mon, 23 Feb 2015 12:28:03 -0600 (CST) From: Sudeep Holla To: linux-arm-kernel@lists.infradead.org, Russell King Subject: [PATCH 1/2] ARM: kernel: add support for cpu cache information Date: Mon, 23 Feb 2015 18:28:10 +0000 Message-Id: <1424716091-22914-1-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 1.9.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150223_102837_062069_66F42460 X-CRM114-Status: GOOD ( 24.47 ) X-Spam-Score: -0.0 (/) Cc: Lorenzo Pieralisi , Will Deacon , Sudeep Holla X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds support for cacheinfo on ARM platforms. On ARMv7, the cache hierarchy can be identified through Cache Level ID register(CLIDR) while the cache geometry is provided by Cache Size ID register(CCSIDR). On architecture versions before ARMv7, CLIDR and CCSIDR is not implemented. The cache type register(CTR) provides both cache hierarchy and geometry if implemented. For implementations that doesn't support CTR, we need to list the probable value of CTR if it was implemented along with the cpuid for the sake of simplicity to handle them. Since the architecture doesn't provide any way of detecting the cpus sharing particular cache, device tree is used fo the same purpose. On non-DT platforms, first level caches are per-cpu while higher level caches are assumed system-wide. This is based on the newly introduced generic cacheinfo infrastructure through the commit 246246cbde5e ("drivers: base: support cpu cache information interface to userspace via sysfs") Signed-off-by: Sudeep Holla Tested-by: Stephen Boyd Cc: Russell King Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org --- arch/arm/kernel/Makefile | 1 + arch/arm/kernel/cacheinfo.c | 282 ++++++++++++++++++++++++++++++++++++++++++++ arch/arm/mm/Kconfig | 13 ++ 3 files changed, 296 insertions(+) create mode 100644 arch/arm/kernel/cacheinfo.c diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 902397dd1000..2551b1a179eb 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -29,6 +29,7 @@ obj-y += entry-v7m.o v7m.o else obj-y += entry-armv.o endif +obj-$(CONFIG_CPU_HAS_CACHE) += cacheinfo.o obj-$(CONFIG_CPU_IDLE) += cpuidle.o obj-$(CONFIG_ISA_DMA_API) += dma.o diff --git a/arch/arm/kernel/cacheinfo.c b/arch/arm/kernel/cacheinfo.c new file mode 100644 index 000000000000..0c4a67dcbcaf --- /dev/null +++ b/arch/arm/kernel/cacheinfo.c @@ -0,0 +1,282 @@ +/* + * ARM cacheinfo support + * + * Copyright (C) 2015 ARM Ltd. + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include + +#include +#include +#include + +#define cache_is_armv7() \ + (cpu_architecture() >= CPU_ARCH_ARMv7 && !armv6_extended()) +#define MAX_CACHE_LEVEL (cache_is_armv7() ? 7 : 1) + +#define CTR_CTYPE_SHIFT 24 +#define CTR_CTYPE_MASK (1 << CTR_CTYPE_SHIFT) + +struct ctr_info { + unsigned int cpuid_part; + unsigned int ctr; +}; + +/* + * Cache Type Register + * +---------------------------------+ + * | 31 29 | 28 25 |24| 23 12 | 11 0 | + * +---------------------------------+ + * | 0 0 0 | Ctype | S| Dsize | Isize| + * +---------------------------------+ + * The table below encodes only Dsize and Isize + */ +static struct ctr_info cache_ctr_list[] = { + {0x4400a100, 0x0016A16A }, /* SA-110: 32kB D$, 32kB I$ */ + {0x4400a110, 0x0012A16A }, /* SA-1100: 16kB D$, 32kB I$ */ + {0x6900b110, 0x0012A16A }, /* SA-1110: 16kB D$, 32kB I$ */ +}; + +/* + * List of CPUs reported as ARMv7 but don't implement CLIDR, + * CSSELR and CCSIDR. Cache information is still available from CTR + */ +static int armv6_ext_cpuid_part[] = { + 0x4100b020, /* ARM11MP */ + 0x4100b760, /* ARM1176 */ +}; + +static bool armv6_extended(void) +{ + int i, cpuid_part = read_cpuid_part(); + + for (i = 0; i < ARRAY_SIZE(armv6_ext_cpuid_part); i++) + if (armv6_ext_cpuid_part[i] == cpuid_part) + return true; + return false; +} + +static int get_unimplemented_ctr(unsigned int *ctr) +{ + int i, cpuid_part = read_cpuid_part(); + + for (i = 0; i < ARRAY_SIZE(cache_ctr_list); i++) + if (cache_ctr_list[i].cpuid_part == cpuid_part) { + *ctr = cache_ctr_list[i].ctr; + return 0; + } + return -ENOENT; +} + +static unsigned int get_ctr(void) +{ + unsigned int ctr; + + if (get_unimplemented_ctr(&ctr)) + ctr = read_cpuid_cachetype(); + return ctr; +} + +static enum cache_type __get_cache_type(int level) +{ + if (level > MAX_CACHE_LEVEL) + return CACHE_TYPE_NOCACHE; + return get_ctr() & CTR_CTYPE_MASK ? + CACHE_TYPE_SEPARATE : CACHE_TYPE_UNIFIED; +} + +/* + * +---------------------------------+ + * | 9 8 7 6 | 5 4 3 | 2 | 1 0 | + * +---------------------------------+ + * | size | assoc | m | len | + * +---------------------------------+ + * linelen = 1 << (len + 3) + * multiplier = 2 + m + * nsets = 1 << (size + 6 - assoc - len) + * associativity = multiplier << (assoc - 1) + * cache_size = multiplier << (size + 8) + */ +#define CTR_LINESIZE_MASK 0x3 +#define CTR_MULTIPLIER_SHIFT 2 +#define CTR_MULTIPLIER_MASK 0x1 +#define CTR_ASSOCIAT_SHIFT 3 +#define CTR_ASSOCIAT_MASK 0x7 +#define CTR_SIZE_SHIFT 6 +#define CTR_SIZE_MASK 0xF +#define CTR_DCACHE_SHIFT 12 + +static void __ci_leaf_init(enum cache_type type, struct cacheinfo *this_leaf) +{ + unsigned int size, multiplier, assoc, len, tmp = get_ctr(); + + if (type == CACHE_TYPE_DATA) + tmp >>= CTR_DCACHE_SHIFT; + + len = tmp & CTR_LINESIZE_MASK; + size = (tmp >> CTR_SIZE_SHIFT) & CTR_SIZE_MASK; + assoc = (tmp >> CTR_ASSOCIAT_SHIFT) & CTR_ASSOCIAT_MASK; + multiplier = ((tmp >> CTR_MULTIPLIER_SHIFT) & CTR_MULTIPLIER_MASK) + 2; + + this_leaf->type = type; + this_leaf->coherency_line_size = 1 << (len + 3); + this_leaf->number_of_sets = 1 << (size + 6 - assoc - len); + this_leaf->ways_of_associativity = multiplier << (assoc - 1); + this_leaf->size = multiplier << (size + 8); +} + +/* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */ +#define CLIDR_CTYPE_SHIFT(level) (3 * (level - 1)) +#define CLIDR_CTYPE_MASK(level) (7 << CLIDR_CTYPE_SHIFT(level)) +#define CLIDR_CTYPE(clidr, level) \ + (((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level)) + +static inline enum cache_type __armv7_get_cache_type(int level) +{ + unsigned int clidr; + + if (level > MAX_CACHE_LEVEL) + return CACHE_TYPE_NOCACHE; + asm volatile ("mrc p15, 1, %0, c0, c0, 1" : "=r" (clidr)); + return CLIDR_CTYPE(clidr, level); +} + +/* + * NumSets, bits[27:13] - (Number of sets in cache) - 1 + * Associativity, bits[12:3] - (Associativity of cache) - 1 + * LineSize, bits[2:0] - (Log2(Number of words in cache line)) - 2 + */ +#define CCSIDR_WRITE_THROUGH BIT(31) +#define CCSIDR_WRITE_BACK BIT(30) +#define CCSIDR_READ_ALLOCATE BIT(29) +#define CCSIDR_WRITE_ALLOCATE BIT(28) +#define CCSIDR_LINESIZE_MASK 0x7 +#define CCSIDR_LINESIZE(x) ((x) & CCSIDR_LINESIZE_MASK) +#define CCSIDR_ASSOCIATIVITY_SHIFT 3 +#define CCSIDR_ASSOCIATIVITY_MASK 0x3ff +#define CCSIDR_ASSOCIATIVITY(x) \ + (((x) >> CCSIDR_ASSOCIATIVITY_SHIFT) & CCSIDR_ASSOCIATIVITY_MASK) +#define CCSIDR_NUMSETS_SHIFT 13 +#define CCSIDR_NUMSETS_MASK 0x7fff +#define CCSIDR_NUMSETS(x) \ + (((x) >> CCSIDR_NUMSETS_SHIFT) & CCSIDR_NUMSETS_MASK) + +#define CACHE_LINESIZE(x) (16 << CCSIDR_LINESIZE(x)) +#define CACHE_NUMSETS(x) (CCSIDR_NUMSETS(x) + 1) +#define CACHE_ASSOCIATIVITY(x) (CCSIDR_ASSOCIATIVITY(x) + 1) + +/* + * Cache Size Selection Register(CSSELR) selects which Cache Size ID + * Register(CCSIDR) is accessible by specifying the required cache + * level and the cache type. We need to ensure that no one else changes + * CSSELR by calling this in non-preemtible context + */ +static u32 __attribute_const__ cache_get_ccsidr(u32 csselr) +{ + u32 ccsidr; + + /* Put value into CSSELR */ + asm volatile ("mcr p15, 2, %0, c0, c0, 0" : : "r" (csselr)); + isb(); + /* Read result out of CCSIDR */ + asm volatile ("mrc p15, 1, %0, c0, c0, 0" : "=r" (ccsidr)); + + return ccsidr; +} + +static void __armv7_ci_leaf_init(enum cache_type type, + struct cacheinfo *this_leaf) +{ + bool is_icache = type & CACHE_TYPE_INST; + u32 tmp = cache_get_ccsidr((this_leaf->level - 1) << 1 | is_icache); + + this_leaf->type = type; + this_leaf->coherency_line_size = CACHE_LINESIZE(tmp); + this_leaf->number_of_sets = CACHE_NUMSETS(tmp); + this_leaf->ways_of_associativity = CACHE_ASSOCIATIVITY(tmp); + this_leaf->size = this_leaf->number_of_sets * + this_leaf->coherency_line_size * this_leaf->ways_of_associativity; + this_leaf->attributes = + ((tmp & CCSIDR_WRITE_THROUGH) ? CACHE_WRITE_THROUGH : 0) | + ((tmp & CCSIDR_WRITE_BACK) ? CACHE_WRITE_BACK : 0) | + ((tmp & CCSIDR_READ_ALLOCATE) ? CACHE_READ_ALLOCATE : 0) | + ((tmp & CCSIDR_WRITE_ALLOCATE) ? CACHE_WRITE_ALLOCATE : 0); +} + +static inline enum cache_type get_cache_type(int level) +{ + if (cache_is_armv7()) + return __armv7_get_cache_type(level); + return __get_cache_type(level); +} + +static void ci_leaf_init(struct cacheinfo *this_leaf, + enum cache_type type, unsigned int level) +{ + this_leaf->level = level; + if (cache_is_armv7()) + __armv7_ci_leaf_init(type, this_leaf); + else + __ci_leaf_init(type, this_leaf); +} + +static int __init_cache_level(unsigned int cpu) +{ + unsigned int ctype, level, leaves; + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); + + for (level = 1, leaves = 0; level <= MAX_CACHE_LEVEL; level++) { + ctype = get_cache_type(level); + if (ctype == CACHE_TYPE_NOCACHE) { + level--; + break; + } + /* Separate instruction and data caches */ + leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1; + } + + this_cpu_ci->num_levels = level; + this_cpu_ci->num_leaves = leaves; + + return 0; +} + +static int __populate_cache_leaves(unsigned int cpu) +{ + unsigned int level, idx; + enum cache_type type; + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); + struct cacheinfo *this_leaf = this_cpu_ci->info_list; + + for (idx = 0, level = 1; level <= this_cpu_ci->num_levels && + idx < this_cpu_ci->num_leaves; idx++, level++) { + type = get_cache_type(level); + if (type == CACHE_TYPE_SEPARATE) { + ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level); + ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level); + } else { + ci_leaf_init(this_leaf++, type, level); + } + } + return 0; +} + +DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level) +DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves) diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 9b4f29e595a4..355ebf108eda 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -494,30 +494,42 @@ config CPU_PABRT_V7 # The cache model config CPU_CACHE_V4 bool + select CPU_HAS_CACHE config CPU_CACHE_V4WT bool + select CPU_HAS_CACHE config CPU_CACHE_V4WB bool + select CPU_HAS_CACHE config CPU_CACHE_V6 bool + select CPU_HAS_CACHE config CPU_CACHE_V7 bool + select CPU_HAS_CACHE config CPU_CACHE_NOP bool + select CPU_HAS_CACHE config CPU_CACHE_VIVT bool + select CPU_HAS_CACHE config CPU_CACHE_VIPT bool + select CPU_HAS_CACHE config CPU_CACHE_FA bool + select CPU_HAS_CACHE + +config CPU_HAS_CACHE + bool if MMU # The copy-page model @@ -846,6 +858,7 @@ config DMA_CACHE_RWFO config OUTER_CACHE bool + select CPU_HAS_CACHE config OUTER_CACHE_SYNC bool