From patchwork Fri Jan 21 16:36:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Heiko_St=C3=BCbner?= X-Patchwork-Id: 533929 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CD4AC433EF for ; Fri, 21 Jan 2022 16:38:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347292AbiAUQi2 (ORCPT ); Fri, 21 Jan 2022 11:38:28 -0500 Received: from gloria.sntech.de ([185.11.138.130]:36132 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233605AbiAUQi1 (ORCPT ); Fri, 21 Jan 2022 11:38:27 -0500 Received: from p508fcef5.dip0.t-ipconnect.de ([80.143.206.245] helo=phil.fritz.box) by gloria.sntech.de with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nAwuT-0008GA-FJ; Fri, 21 Jan 2022 17:37:09 +0100 From: Heiko Stuebner To: palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu Cc: linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, wefu@redhat.com, liush@allwinnertech.com, guoren@kernel.org, atishp@atishpatra.org, anup@brainfault.org, drew@beagleboard.org, hch@lst.de, arnd@arndb.de, wens@csie.org, maxime@cerno.tech, dlustig@nvidia.com, gfavor@ventanamicro.com, andrea.mondelli@huawei.com, behrensj@mit.edu, xinhaoqu@huawei.com, huffman@cadence.com, mick@ics.forth.gr, allen.baum@esperantotech.com, jscheid@ventanamicro.com, rtrauben@gmail.com, samuel@sholland.org, cmuellner@linux.com, philipp.tomsich@vrull.eu, Heiko Stuebner Subject: [PATCH v5 14/14] riscv: add memory-type errata for T-Head Date: Fri, 21 Jan 2022 17:36:18 +0100 Message-Id: <20220121163618.351934-15-heiko@sntech.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220121163618.351934-1-heiko@sntech.de> References: <20220121163618.351934-1-heiko@sntech.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Some current cpus based on T-Head cores implement memory-types way different than described in the svpbmt spec even going so far as using PTE bits marked as reserved. Add the T-Head vendor-id and necessary errata code to replace the affected instructions. Signed-off-by: Heiko Stuebner --- arch/riscv/Kconfig.erratas | 19 ++++++ arch/riscv/errata/Makefile | 1 + arch/riscv/errata/sifive/errata.c | 7 ++- arch/riscv/errata/thead/Makefile | 1 + arch/riscv/errata/thead/errata.c | 85 ++++++++++++++++++++++++++ arch/riscv/include/asm/alternative.h | 5 ++ arch/riscv/include/asm/errata_list.h | 47 ++++++++++++-- arch/riscv/include/asm/pgtable-64.h | 18 +++++- arch/riscv/include/asm/pgtable.h | 18 +++++- arch/riscv/include/asm/vendorid_list.h | 1 + arch/riscv/kernel/alternative.c | 14 +++++ arch/riscv/kernel/cpufeature.c | 2 + arch/riscv/mm/init.c | 2 + 13 files changed, 211 insertions(+), 9 deletions(-) create mode 100644 arch/riscv/errata/thead/Makefile create mode 100644 arch/riscv/errata/thead/errata.c diff --git a/arch/riscv/Kconfig.erratas b/arch/riscv/Kconfig.erratas index d18be8ff0245..380ec039c3dc 100644 --- a/arch/riscv/Kconfig.erratas +++ b/arch/riscv/Kconfig.erratas @@ -31,4 +31,23 @@ config ERRATA_SIFIVE_CIP_1200 If you don't know what to do here, say "Y". +config ERRATA_THEAD + bool "T-HEAD errata" + help + All T-HEAD errata Kconfig depend on this Kconfig. Disabling + this Kconfig will disable all T-HEAD errata. Please say "Y" + here if your platform uses T-HEAD CPU cores. + + If you don't know what to do here, say "Y". + +config ERRATA_THEAD_PBMT + bool "Apply T-Head memory type errata" + depends on ERRATA_THEAD && 64BIT + default y + help + This will apply the memory type errata to handle the non-standard + memory type bits in page-table-entries on T-Head SoCs. + + If you don't know what to do here, say "Y". + endmenu diff --git a/arch/riscv/errata/Makefile b/arch/riscv/errata/Makefile index 0ca1c5281a2d..a1055965fbee 100644 --- a/arch/riscv/errata/Makefile +++ b/arch/riscv/errata/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_ERRATA_SIFIVE) += sifive/ +obj-$(CONFIG_ERRATA_THEAD) += thead/ diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c index 4fe03ac41fd7..f933d6cdf304 100644 --- a/arch/riscv/errata/sifive/errata.c +++ b/arch/riscv/errata/sifive/errata.c @@ -84,10 +84,15 @@ void __init sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry * unsigned int stage) { struct alt_entry *alt; - u32 cpu_req_errata = sifive_errata_probe(archid, impid); + u32 cpu_req_errata; u32 cpu_apply_errata = 0; u32 tmp; + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + return; + + cpu_req_errata = sifive_errata_probe(archid, impid); + for (alt = begin; alt < end; alt++) { if (alt->vendor_id != SIFIVE_VENDOR_ID) continue; diff --git a/arch/riscv/errata/thead/Makefile b/arch/riscv/errata/thead/Makefile new file mode 100644 index 000000000000..2d644e19caef --- /dev/null +++ b/arch/riscv/errata/thead/Makefile @@ -0,0 +1 @@ +obj-y += errata.o diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c new file mode 100644 index 000000000000..fd8e0538a3f0 --- /dev/null +++ b/arch/riscv/errata/thead/errata.c @@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 Heiko Stuebner + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct errata_info { + char name[ERRATA_STRING_LENGTH_MAX]; + bool (*check_func)(unsigned long arch_id, unsigned long impid); + unsigned int stage; +}; + +static bool errata_mt_check_func(unsigned long arch_id, unsigned long impid) +{ + if (arch_id != 0 || impid != 0) + return false; + return true; +} + +static const struct errata_info errata_list[ERRATA_THEAD_NUMBER] = { + { + .name = "memory-types", + .stage = RISCV_ALTERNATIVES_EARLY_BOOT, + .check_func = errata_mt_check_func + }, +}; + +static u32 thead_errata_probe(unsigned int stage, unsigned long archid, unsigned long impid) +{ + const struct errata_info *info; + u32 cpu_req_errata = 0; + int idx; + + for (idx = 0; idx < ERRATA_THEAD_NUMBER; idx++) { + info = &errata_list[idx]; + + if ((stage == RISCV_ALTERNATIVES_MODULE || + info->stage == stage) && info->check_func(archid, impid)) + cpu_req_errata |= (1U << idx); + } + + return cpu_req_errata; +} + +void __init_or_module thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, + unsigned long archid, unsigned long impid, + unsigned int stage) +{ + struct alt_entry *alt; + u32 cpu_req_errata = thead_errata_probe(stage, archid, impid); + u32 cpu_apply_errata = 0; + u32 tmp; + + for (alt = begin; alt < end; alt++) { + if (alt->vendor_id != THEAD_VENDOR_ID) + continue; + if (alt->errata_id >= ERRATA_THEAD_NUMBER) + continue; + + tmp = (1U << alt->errata_id); + if (cpu_req_errata & tmp) { + /* On vm-alternatives, the mmu isn't running yet */ + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + memcpy((void *)__pa_symbol(alt->old_ptr), + (void *)__pa_symbol(alt->alt_ptr), alt->alt_len); + else + patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len); + + cpu_apply_errata |= tmp; + } + } + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + local_flush_icache_all(); +} diff --git a/arch/riscv/include/asm/alternative.h b/arch/riscv/include/asm/alternative.h index cf3b22173834..d1154c91ab03 100644 --- a/arch/riscv/include/asm/alternative.h +++ b/arch/riscv/include/asm/alternative.h @@ -19,8 +19,10 @@ #define RISCV_ALTERNATIVES_BOOT 0 /* alternatives applied during regular boot */ #define RISCV_ALTERNATIVES_MODULE 1 /* alternatives applied during module-init */ +#define RISCV_ALTERNATIVES_EARLY_BOOT 2 /* alternatives applied before mmu start */ void __init apply_boot_alternatives(void); +void __init apply_early_boot_alternatives(void); void apply_module_alternatives(void *start, size_t length); struct alt_entry { @@ -39,6 +41,9 @@ struct errata_checkfunc_id { void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, unsigned long archid, unsigned long impid, unsigned int stage); +void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, + unsigned long archid, unsigned long impid, + unsigned int stage); void riscv_cpufeature_patch_func(struct alt_entry *begin, struct alt_entry *end, unsigned int stage); diff --git a/arch/riscv/include/asm/errata_list.h b/arch/riscv/include/asm/errata_list.h index a4a9b0842922..4fac46b82c16 100644 --- a/arch/riscv/include/asm/errata_list.h +++ b/arch/riscv/include/asm/errata_list.h @@ -14,6 +14,11 @@ #define ERRATA_SIFIVE_NUMBER 2 #endif +#ifdef CONFIG_ERRATA_THEAD +#define ERRATA_THEAD_PBMT 0 +#define ERRATA_THEAD_NUMBER 1 +#endif + #define CPUFEATURE_SVPBMT 0 #define CPUFEATURE_NUMBER 1 @@ -42,10 +47,44 @@ asm(ALTERNATIVE("sfence.vma %0", "sfence.vma", SIFIVE_VENDOR_ID, \ * in the default case. */ #define ALT_SVPBMT_SHIFT 61 -#define ALT_SVPBMT(_val, prot) \ -asm(ALTERNATIVE("li %0, 0\t\nnop", "li %0, %1\t\nslli %0,%0,%2", 0, \ - CPUFEATURE_SVPBMT, CONFIG_64BIT) \ - : "=r"(_val) : "I"(prot##_SVPBMT >> ALT_SVPBMT_SHIFT), "I"(ALT_SVPBMT_SHIFT)) +#define ALT_THEAD_PBMT_SHIFT 59 +#define ALT_SVPBMT(_val, prot) \ +asm(ALTERNATIVE_2("li %0, 0\t\nnop", \ + "li %0, %1\t\nslli %0,%0,%3", 0, CPUFEATURE_SVPBMT, CONFIG_64BIT, \ + "li %0, %2\t\nslli %0,%0,%4", THEAD_VENDOR_ID, ERRATA_THEAD_PBMT, \ + CONFIG_ERRATA_THEAD_PBMT) \ + : "=r"(_val) : "I"(prot##_SVPBMT >> ALT_SVPBMT_SHIFT), \ + "I"(prot##_THEAD >> ALT_THEAD_PBMT_SHIFT), \ + "I"(ALT_SVPBMT_SHIFT), "I"(ALT_THEAD_PBMT_SHIFT)) + +#ifdef CONFIG_ERRATA_THEAD_PBMT +/* + * IO/NOCACHE memory types are handled together with svpbmt, + * so on T-Head chips, check if no other memory type is set, + * and set the non-0 PMA type if applicable. + */ +#define ALT_THEAD_PMA(_val) \ +asm volatile(ALTERNATIVE( \ + "nop\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + "nop\n\t" \ + "nop", \ + "li t3, %2\n\t" \ + "slli t3, t3, %4\n\t" \ + "and t3, %0, t3\n\t" \ + "bne t3, zero, 2f\n\t" \ + "li t3, %3\n\t" \ + "slli t3, t3, %4\n\t" \ + "or %0, %0, t3\n\t" \ + "2:", THEAD_VENDOR_ID, ERRATA_THEAD_PBMT, CONFIG_ERRATA_THEAD_PBMT) \ + : "+r"(_val) : "0"(_val), "I"(_PAGE_MTMASK_THEAD >> ALT_THEAD_PBMT_SHIFT), \ + "I"(_PAGE_PMA_THEAD >> ALT_THEAD_PBMT_SHIFT), "I"(ALT_THEAD_PBMT_SHIFT)) +#else +#define ALT_THEAD_PMA(_val) +#endif #endif /* __ASSEMBLY__ */ diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h index 58b34ef74acb..e7ce01cdc235 100644 --- a/arch/riscv/include/asm/pgtable-64.h +++ b/arch/riscv/include/asm/pgtable-64.h @@ -49,6 +49,18 @@ typedef struct { #define _PAGE_IO_SVPBMT (1UL << 62) #define _PAGE_MTMASK_SVPBMT (_PAGE_NOCACHE_SVPBMT | _PAGE_IO_SVPBMT) +/* + * [63:59] T-Head Memory Type definitions: + * + * 00000 - NC Weakly-ordered, Non-cacheable, Non-bufferable, Non-shareable, Non-trustable + * 01110 - PMA Weakly-ordered, Cacheable, Bufferable, Shareable, Non-trustable + * 10000 - IO Strongly-ordered, Non-cacheable, Non-bufferable, Non-shareable, Non-trustable + */ +#define _PAGE_PMA_THEAD ((1UL << 62) | (1UL << 61) | (1UL << 60)) +#define _PAGE_NOCACHE_THEAD 0UL +#define _PAGE_IO_THEAD (1UL << 63) +#define _PAGE_MTMASK_THEAD (_PAGE_PMA_THEAD | _PAGE_IO_THEAD | (1UL << 59)) + static inline u64 riscv_page_mtmask(void) { u64 val; @@ -126,7 +138,11 @@ static inline struct page *pud_page(pud_t pud) static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot) { - return __pmd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot)); + unsigned long prot_val = pgprot_val(prot); + + ALT_THEAD_PMA(prot_val); + + return __pmd((pfn << _PAGE_PFN_SHIFT) | prot_val); } static inline unsigned long _pmd_pfn(pmd_t pmd) diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index a189a21a7c8a..c3b9220b2523 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -219,7 +219,11 @@ static inline void pmd_clear(pmd_t *pmdp) static inline pgd_t pfn_pgd(unsigned long pfn, pgprot_t prot) { - return __pgd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot)); + unsigned long prot_val = pgprot_val(prot); + + ALT_THEAD_PMA(prot_val); + + return __pgd((pfn << _PAGE_PFN_SHIFT) | prot_val); } static inline unsigned long _pgd_pfn(pgd_t pgd) @@ -258,7 +262,11 @@ static inline unsigned long pte_pfn(pte_t pte) /* Constructs a page table entry */ static inline pte_t pfn_pte(unsigned long pfn, pgprot_t prot) { - return __pte((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot)); + unsigned long prot_val = pgprot_val(prot); + + ALT_THEAD_PMA(prot_val); + + return __pte((pfn << _PAGE_PFN_SHIFT) | prot_val); } #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot) @@ -367,7 +375,11 @@ static inline int pmd_protnone(pmd_t pmd) /* Modify page protection bits */ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { - return __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)); + unsigned long newprot_val = pgprot_val(newprot); + + ALT_THEAD_PMA(newprot_val); + + return __pte((pte_val(pte) & _PAGE_CHG_MASK) | newprot_val); } #define pgd_ERROR(e) \ diff --git a/arch/riscv/include/asm/vendorid_list.h b/arch/riscv/include/asm/vendorid_list.h index 9d934215b3c8..cb89af3f0704 100644 --- a/arch/riscv/include/asm/vendorid_list.h +++ b/arch/riscv/include/asm/vendorid_list.h @@ -6,5 +6,6 @@ #define ASM_VENDOR_LIST_H #define SIFIVE_VENDOR_ID 0x489 +#define THEAD_VENDOR_ID 0x5b7 #endif diff --git a/arch/riscv/kernel/alternative.c b/arch/riscv/kernel/alternative.c index 54913857b682..e272599f96ef 100644 --- a/arch/riscv/kernel/alternative.c +++ b/arch/riscv/kernel/alternative.c @@ -48,6 +48,11 @@ static void __init init_alternative(void) case SIFIVE_VENDOR_ID: vendor_patch_func = sifive_errata_patch_func; break; +#endif +#ifdef CONFIG_ERRATA_THEAD + case THEAD_VENDOR_ID: + vendor_patch_func = thead_errata_patch_func; + break; #endif default: vendor_patch_func = NULL; @@ -85,6 +90,15 @@ void __init apply_boot_alternatives(void) RISCV_ALTERNATIVES_BOOT); } +void __init apply_early_boot_alternatives(void) +{ + init_alternative(); + + _apply_alternatives((struct alt_entry *)__alt_start, + (struct alt_entry *)__alt_end, + RISCV_ALTERNATIVES_EARLY_BOOT); +} + #ifdef CONFIG_MODULES void apply_module_alternatives(void *start, size_t length) { diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index d14289fba055..4ed18981d94d 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -224,6 +224,8 @@ static bool cpufeature_svpbmt_check_func(unsigned int stage) #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) switch (stage) { + case RISCV_ALTERNATIVES_EARLY_BOOT: + return false; case RISCV_ALTERNATIVES_BOOT: return cpufeature_svpbmt_check_fdt(); default: diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 24b2b8044602..063d5f022a05 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -624,6 +624,8 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); #endif + apply_early_boot_alternatives(); + pt_ops.alloc_pte = alloc_pte_early; pt_ops.get_pte_virt = get_pte_virt_early; #ifndef __PAGETABLE_PMD_FOLDED