From: Sia Jee Heng <jeeheng.sia@starfivetech.com>
Date: Mon, 17 Oct 2022 02:25:05 +0000 (+0800)
Subject: riscv: kernel: Expand functionlity of swsusp_arch_suspend for JH7110
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=90957965b19514a7f82b1e97a516db2724c40f0a;p=platform%2Fkernel%2Flinux-starfive.git

riscv: kernel: Expand functionlity of swsusp_arch_suspend for JH7110

Futher expand the functionality of the swsusp_arch_suspend so that the
hibernated image can be written to the disk and resume from the
hibernated image.

Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com>
---

diff --git a/arch/riscv/include/asm/suspend.h b/arch/riscv/include/asm/suspend.h
index 9a5880c452b8..9a98e0db6648 100644
--- a/arch/riscv/include/asm/suspend.h
+++ b/arch/riscv/include/asm/suspend.h
@@ -21,6 +21,11 @@ struct suspend_context {
 #endif
 };
 
+/* This value will be assigned to 0 during resume and will be used by
+ * hibernation core for the subsequent resume sequence
+ */
+extern int in_suspend;
+
 /* Low-level CPU suspend entry function */
 int __cpu_suspend_enter(struct suspend_context *context);
 
@@ -42,4 +47,7 @@ int arch_hibernation_header_restore(void *addr);
 /* Used to resume on the CPU we hibernated on */
 int hibernate_resume_nonboot_cpu_disable(void);
 
+/* Used to save and restore the csr */
+void suspend_save_csrs(struct suspend_context *context);
+void suspend_restore_csrs(struct suspend_context *context);
 #endif
diff --git a/arch/riscv/kernel/hibernate.c b/arch/riscv/kernel/hibernate.c
index 83471b76ab79..603c43543e99 100644
--- a/arch/riscv/kernel/hibernate.c
+++ b/arch/riscv/kernel/hibernate.c
@@ -30,6 +30,9 @@
  */
 static int sleep_cpu = -EINVAL;
 
+/* CPU context to be saved */
+struct suspend_context context = { 0 };
+
 /*
  * Values that may not change over hibernate/resume. We put the build number
  * and date in here so that we guarantee not to resume with a different
@@ -123,7 +126,25 @@ EXPORT_SYMBOL(arch_hibernation_header_restore);
 
 int swsusp_arch_suspend(void)
 {
-	return 0;
+	int ret = 0;
+
+	if (__cpu_suspend_enter(&context)) {
+		sleep_cpu = smp_processor_id();
+		suspend_save_csrs(&context);
+		ret = swsusp_save();
+	} else {
+		local_flush_icache_all();
+
+		/*
+		 * Tell the hibernation core that we've just restored
+		 * the memory
+		 */
+		in_suspend = 0;
+
+		sleep_cpu = -EINVAL;
+	}
+
+	return ret;
 }
 
 int swsusp_arch_resume(void)
diff --git a/arch/riscv/kernel/suspend.c b/arch/riscv/kernel/suspend.c
index 9ba24fb8cc93..3c89b8ec69c4 100644
--- a/arch/riscv/kernel/suspend.c
+++ b/arch/riscv/kernel/suspend.c
@@ -8,7 +8,7 @@
 #include <asm/csr.h>
 #include <asm/suspend.h>
 
-static void suspend_save_csrs(struct suspend_context *context)
+void suspend_save_csrs(struct suspend_context *context)
 {
 	context->scratch = csr_read(CSR_SCRATCH);
 	context->tvec = csr_read(CSR_TVEC);
@@ -29,7 +29,7 @@ static void suspend_save_csrs(struct suspend_context *context)
 #endif
 }
 
-static void suspend_restore_csrs(struct suspend_context *context)
+void suspend_restore_csrs(struct suspend_context *context)
 {
 	csr_write(CSR_SCRATCH, context->scratch);
 	csr_write(CSR_TVEC, context->tvec);