diff options
Diffstat (limited to 'lib/sbi/sbi_fwft.c')
| -rw-r--r-- | lib/sbi/sbi_fwft.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/lib/sbi/sbi_fwft.c b/lib/sbi/sbi_fwft.c new file mode 100644 index 0000000..b302b5d --- /dev/null +++ b/lib/sbi/sbi_fwft.c @@ -0,0 +1,178 @@ +/* + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2024 Rivos Inc. + * + * Authors: + * Clément Léger <cleger@rivosinc.com> + */ + +#include <sbi/sbi_console.h> +#include <sbi/sbi_bitmap.h> +#include <sbi/sbi_ecall_interface.h> +#include <sbi/sbi_error.h> +#include <sbi/sbi_hart.h> +#include <sbi/sbi_heap.h> +#include <sbi/sbi_scratch.h> +#include <sbi/sbi_string.h> +#include <sbi/sbi_types.h> + +#include <sbi/riscv_asm.h> +#include <sbi/riscv_encoding.h> + +/** Offset of pointer to FWFT HART state in scratch space */ +static unsigned long fwft_ptr_offset; + +#define fwft_get_hart_state_ptr(__scratch) \ + sbi_scratch_read_type((__scratch), void *, fwft_ptr_offset) + +#define fwft_thishart_state_ptr() \ + fwft_get_hart_state_ptr(sbi_scratch_thishart_ptr()) + +#define fwft_set_hart_state_ptr(__scratch, __phs) \ + sbi_scratch_write_type((__scratch), void *, fwft_ptr_offset, (__phs)) + +struct fwft_config; + +struct fwft_feature { + enum sbi_fwft_feature_t id; + int (*supported)(struct fwft_config *conf); + int (*set)(struct fwft_config *conf, unsigned long value); + int (*get)(struct fwft_config *conf, unsigned long *value); +}; + +struct fwft_config { + const struct fwft_feature *feature; + unsigned long flags; +}; + +struct fwft_hart_state { + unsigned int config_count; + struct fwft_config configs[]; +}; + +static const unsigned long fwft_defined_features[] = { + SBI_FWFT_MISALIGNED_EXC_DELEG, + SBI_FWFT_LANDING_PAD, + SBI_FWFT_SHADOW_STACK, + SBI_FWFT_DOUBLE_TRAP, + SBI_FWFT_PTE_AD_HW_UPDATING, +}; + +static bool fwft_is_defined_feature(enum sbi_fwft_feature_t feature) +{ + int i; + + for (i = 0; i < array_size(fwft_defined_features); i++) { + if (fwft_defined_features[i] == feature) + return true; + } + + return false; +} + +static struct fwft_config* get_feature_config(enum sbi_fwft_feature_t feature) +{ + int i; + struct fwft_hart_state *fhs = fwft_thishart_state_ptr(); + + if (feature & SBI_FWFT_GLOBAL_FEATURE_BIT) + return NULL; + + for (i = 0; i < fhs->config_count; i++){ + if (feature == fhs->configs[i].feature->id) + return &fhs->configs[i]; + } + + return NULL; +} + +static int fwft_get_feature(enum sbi_fwft_feature_t feature, + struct fwft_config **conf) +{ + int ret; + struct fwft_config *tconf; + + tconf = get_feature_config(feature); + if (!tconf) { + if (fwft_is_defined_feature(feature)) + return SBI_ENOTSUPP; + + return SBI_EDENIED; + } + + if (tconf->feature->supported) { + ret = tconf->feature->supported(tconf); + if (ret) + return ret; + } + *conf = tconf; + + return SBI_SUCCESS; +} + +int sbi_fwft_set(enum sbi_fwft_feature_t feature, unsigned long value, + unsigned long flags) +{ + int ret; + struct fwft_config *conf; + + ret = fwft_get_feature(feature, &conf); + if (ret) + return ret; + + if ((flags & ~SBI_FWFT_SET_FLAG_LOCK) != 0) + return SBI_ERR_INVALID_PARAM; + + if (conf->flags & SBI_FWFT_SET_FLAG_LOCK) + return SBI_EDENIED; + + ret = conf->feature->set(conf, value); + if (ret) + return ret; + + conf->flags = flags; + + return SBI_OK; +} + +int sbi_fwft_get(enum sbi_fwft_feature_t feature, unsigned long *out_val) +{ + int ret; + struct fwft_config *conf; + + ret = fwft_get_feature(feature, &conf); + if (ret) + return ret; + + return conf->feature->get(conf, out_val); +} + +static const struct fwft_feature features[] = {}; + +int sbi_fwft_init(struct sbi_scratch *scratch, bool cold_boot) +{ + int i; + struct fwft_hart_state *fhs; + + if (cold_boot) { + fwft_ptr_offset = sbi_scratch_alloc_type_offset(void *); + if (!fwft_ptr_offset) + return SBI_ENOMEM; + } + + fhs = fwft_get_hart_state_ptr(scratch); + if (!fhs) { + fhs = sbi_zalloc(sizeof(fhs) + array_size(features) * sizeof(struct fwft_config)); + if (!fhs) + return SBI_ENOMEM; + + fhs->config_count = array_size(features); + for (i = 0; i < array_size(features); i++) + fhs->configs[i].feature = &features[i]; + + fwft_set_hart_state_ptr(scratch, fhs); + } + + return 0; +} |