linux-kernel - [PATCH v2 2/3] riscv: Add stimecmp save and restore

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240926065422.226518-3-nick.hu@sifive.com>
Date: Thu, 26 Sep 2024 14:54:17 +0800
From: Nick Hu <nick.hu@...ive.com>
To: greentime.hu@...ive.com,
	zong.li@...ive.com,
	Paul Walmsley <paul.walmsley@...ive.com>,
	Palmer Dabbelt <palmer@...belt.com>,
	Albert Ou <aou@...s.berkeley.edu>,
	"Rafael J. Wysocki" <rafael@...nel.org>,
	Pavel Machek <pavel@....cz>,
	Daniel Lezcano <daniel.lezcano@...aro.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Anup Patel <anup@...infault.org>,
	Andrew Jones <ajones@...tanamicro.com>,
	Conor Dooley <conor.dooley@...rochip.com>,
	Mayuresh Chitale <mchitale@...tanamicro.com>,
	Atish Patra <atishp@...osinc.com>,
	Samuel Holland <samuel.holland@...ive.com>,
	Samuel Ortiz <sameo@...osinc.com>,
	Nick Hu <nick.hu@...ive.com>,
	Sunil V L <sunilvl@...tanamicro.com>,
	linux-riscv@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	linux-pm@...r.kernel.org
Subject: [PATCH v2 2/3] riscv: Add stimecmp save and restore

If the HW support the SSTC extension, we should save and restore the
stimecmp register while cpu non retention suspend.

Signed-off-by: Nick Hu <nick.hu@...ive.com>
---
 arch/riscv/include/asm/suspend.h | 1 +
 arch/riscv/kernel/suspend.c      | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/arch/riscv/include/asm/suspend.h b/arch/riscv/include/asm/suspend.h
index 4ffb022b097f..4dfdb7134d0e 100644
--- a/arch/riscv/include/asm/suspend.h
+++ b/arch/riscv/include/asm/suspend.h
@@ -18,6 +18,7 @@ struct suspend_context {
 	unsigned long ie;
 #ifdef CONFIG_MMU
 	unsigned long satp;
+	u64 stimecmp;
 #endif
 };
 
diff --git a/arch/riscv/kernel/suspend.c b/arch/riscv/kernel/suspend.c
index c8cec0cc5833..5d9036ea6784 100644
--- a/arch/riscv/kernel/suspend.c
+++ b/arch/riscv/kernel/suspend.c
@@ -30,6 +30,9 @@ void suspend_save_csrs(struct suspend_context *context)
 	 */
 
 #ifdef CONFIG_MMU
+	if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SSTC))
+		context->stimecmp = csr_read_hi_lo(CSR_STIMECMP);
+
 	context->satp = csr_read(CSR_SATP);
 #endif
 }
@@ -43,6 +46,9 @@ void suspend_restore_csrs(struct suspend_context *context)
 	csr_write(CSR_IE, context->ie);
 
 #ifdef CONFIG_MMU
+	if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SSTC))
+		csr_write_hi_lo(CSR_STIMECMP, context->stimecmp);
+
 	csr_write(CSR_SATP, context->satp);
 #endif
 }
-- 
2.34.1