From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anup Patel Date: Tue, 29 Mar 2022 21:22:16 +0530 Subject: [PATCH 2/4] lib: sbi: Detect menvcfg CSR at boot time In-Reply-To: <20220329155218.118580-1-apatel@ventanamicro.com> References: <20220329155218.118580-1-apatel@ventanamicro.com> Message-ID: <20220329155218.118580-3-apatel@ventanamicro.com> List-Id: To: opensbi@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit From: Atish Patra We add the menvcfg CSR as a HART feature and detect it at boot time using traping mechanism. Signed-off-by: Atish Patra Signed-off-by: Anup Patel --- include/sbi/sbi_hart.h | 4 +++- lib/sbi/sbi_hart.c | 9 +++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/include/sbi/sbi_hart.h b/include/sbi/sbi_hart.h index a83b45b..57f80bc 100644 --- a/include/sbi/sbi_hart.h +++ b/include/sbi/sbi_hart.h @@ -26,9 +26,11 @@ enum sbi_hart_features { SBI_HART_HAS_TIME = (1 << 4), /** HART has AIA local interrupt CSRs */ SBI_HART_HAS_AIA = (1 << 5), + /** HART has menvcfg CSR */ + SBI_HART_HAS_MENVCFG = (1 << 6), /** Last index of Hart features*/ - SBI_HART_HAS_LAST_FEATURE = SBI_HART_HAS_AIA, + SBI_HART_HAS_LAST_FEATURE = SBI_HART_HAS_MENVCFG, }; struct sbi_scratch; diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c index e028540..31c8f39 100644 --- a/lib/sbi/sbi_hart.c +++ b/lib/sbi/sbi_hart.c @@ -304,6 +304,9 @@ static inline char *sbi_hart_feature_id2string(unsigned long feature) case SBI_HART_HAS_AIA: fstr = "aia"; break; + case SBI_HART_HAS_MENVCFG: + fstr = "menvcfg"; + break; default: break; } @@ -534,6 +537,12 @@ __mhpm_skip: goto __aia_skip; hfeatures->features |= SBI_HART_HAS_AIA; __aia_skip: + + /* Detect if hart has menvcfg CSR */ + csr_read_allowed(CSR_MENVCFG, (unsigned long)&trap); + if (!trap.cause) + hfeatures->features |= SBI_HART_HAS_MENVCFG; + return; } -- 2.25.1