From ba4cd855839daa2e13f251b2e9db28e5b03b5f40 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Cl=C3=A9ment=20L=C3=A9ger?= Date: Wed, 19 Jun 2024 13:35:18 +0200 Subject: [PATCH] riscv: add ISA parsing for Zca, Zcf, Zcd and Zcb MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The Zc* standard extension for code reduction introduces new extensions. This patch adds support for Zca, Zcf, Zcd and Zcb. Zce, Zcmt and Zcmp are left out of this patch since they are targeting microcontrollers/ embedded CPUs instead of application processors. Signed-off-by: Clément Léger Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20240619113529.676940-9-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/hwcap.h | 4 +++ arch/riscv/kernel/cpufeature.c | 55 +++++++++++++++++++++++++++++++++- 2 files changed, 58 insertions(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index 18859277843ae..b12ae3f2141c1 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -87,6 +87,10 @@ #define RISCV_ISA_EXT_ZVE64F 78 #define RISCV_ISA_EXT_ZVE64D 79 #define RISCV_ISA_EXT_ZIMOP 80 +#define RISCV_ISA_EXT_ZCA 81 +#define RISCV_ISA_EXT_ZCB 82 +#define RISCV_ISA_EXT_ZCD 83 +#define RISCV_ISA_EXT_ZCF 84 #define RISCV_ISA_EXT_XLINUXENVCFG 127 diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index a3af976f36c9a..aa631fe49b7ca 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -111,6 +111,9 @@ static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data, #define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, NULL) +#define __RISCV_ISA_EXT_DATA_VALIDATE(_name, _id, _validate) \ + _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0, _validate) + /* Used to declare pure "lasso" extension (Zk for instance) */ #define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \ _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, \ @@ -122,6 +125,37 @@ static int riscv_ext_zicboz_validate(const struct riscv_isa_ext_data *data, #define __RISCV_ISA_EXT_SUPERSET_VALIDATE(_name, _id, _sub_exts, _validate) \ _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts), _validate) +static int riscv_ext_zca_depends(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA)) + return 0; + + return -EPROBE_DEFER; +} +static int riscv_ext_zcd_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) && + __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_d)) + return 0; + + return -EPROBE_DEFER; +} + +static int riscv_ext_zcf_validate(const struct riscv_isa_ext_data *data, + const unsigned long *isa_bitmap) +{ + if (IS_ENABLED(CONFIG_64BIT)) + return -EINVAL; + + if (__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_ZCA) && + __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_f)) + return 0; + + return -EPROBE_DEFER; +} + static const unsigned int riscv_zk_bundled_exts[] = { RISCV_ISA_EXT_ZBKB, RISCV_ISA_EXT_ZBKC, @@ -236,6 +270,21 @@ static const unsigned int riscv_xlinuxenvcfg_exts[] = { RISCV_ISA_EXT_XLINUXENVCFG }; +/* + * Zc* spec states that: + * - C always implies Zca + * - C+F implies Zcf (RV32 only) + * - C+D implies Zcd + * + * These extensions will be enabled and then validated depending on the + * availability of F/D RV32. + */ +static const unsigned int riscv_c_exts[] = { + RISCV_ISA_EXT_ZCA, + RISCV_ISA_EXT_ZCF, + RISCV_ISA_EXT_ZCD, +}; + /* * The canonical order of ISA extension names in the ISA string is defined in * chapter 27 of the unprivileged specification. @@ -282,7 +331,7 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = { __RISCV_ISA_EXT_DATA(f, RISCV_ISA_EXT_f), __RISCV_ISA_EXT_DATA(d, RISCV_ISA_EXT_d), __RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q), - __RISCV_ISA_EXT_DATA(c, RISCV_ISA_EXT_c), + __RISCV_ISA_EXT_SUPERSET(c, RISCV_ISA_EXT_c, riscv_c_exts), __RISCV_ISA_EXT_SUPERSET(v, RISCV_ISA_EXT_v, riscv_v_exts), __RISCV_ISA_EXT_DATA(h, RISCV_ISA_EXT_h), __RISCV_ISA_EXT_SUPERSET_VALIDATE(zicbom, RISCV_ISA_EXT_ZICBOM, riscv_xlinuxenvcfg_exts, @@ -301,6 +350,10 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = { __RISCV_ISA_EXT_DATA(zfa, RISCV_ISA_EXT_ZFA), __RISCV_ISA_EXT_DATA(zfh, RISCV_ISA_EXT_ZFH), __RISCV_ISA_EXT_DATA(zfhmin, RISCV_ISA_EXT_ZFHMIN), + __RISCV_ISA_EXT_DATA(zca, RISCV_ISA_EXT_ZCA), + __RISCV_ISA_EXT_DATA_VALIDATE(zcb, RISCV_ISA_EXT_ZCB, riscv_ext_zca_depends), + __RISCV_ISA_EXT_DATA_VALIDATE(zcd, RISCV_ISA_EXT_ZCD, riscv_ext_zcd_validate), + __RISCV_ISA_EXT_DATA_VALIDATE(zcf, RISCV_ISA_EXT_ZCF, riscv_ext_zcf_validate), __RISCV_ISA_EXT_DATA(zba, RISCV_ISA_EXT_ZBA), __RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB), __RISCV_ISA_EXT_DATA(zbc, RISCV_ISA_EXT_ZBC), -- 2.39.5