lib: sbi: Simplify system reset platform operations

Instead of having system_reset_check() and system_reset() callbacks
in platform operations, it will be much simpler for reset driver to
directly register these operations as a device to the sbi_system
implementation.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

lib/sbi/sbi_system.c

@@ -18,10 +18,25 @@
 #include <sbi/sbi_ipi.h>
 #include <sbi/sbi_init.h>
 
+static const struct sbi_system_reset_device *reset_dev = NULL;
+
+const struct sbi_system_reset_device *sbi_system_reset_get_device(void)
+{
+	return reset_dev;
+}
+
+void sbi_system_reset_set_device(const struct sbi_system_reset_device *dev)
+{
+	if (!dev || reset_dev)
+		return;
+
+	reset_dev = dev;
+}
+
 bool sbi_system_reset_supported(u32 reset_type, u32 reset_reason)
 {
-	if (sbi_platform_system_reset_check(sbi_platform_thishart_ptr(),
-					    reset_type, reset_reason))
+	if (reset_dev && reset_dev->system_reset_check &&
+	    reset_dev->system_reset_check(reset_type, reset_reason))
 		return TRUE;
 
 	return FALSE;
@@ -47,9 +62,9 @@ void __noreturn sbi_system_reset(u32 reset_type, u32 reset_reason)
 	sbi_hsm_hart_stop(scratch, FALSE);
 
 	/* Platform specific reset if domain allowed system reset */
-	if (dom->system_reset_allowed)
-		sbi_platform_system_reset(sbi_platform_ptr(scratch),
-					  reset_type, reset_reason);
+	if (dom->system_reset_allowed &&
+	    reset_dev && reset_dev->system_reset)
+		reset_dev->system_reset(reset_type, reset_reason);
 
 	/* If platform specific reset did not work then do sbi_exit() */
 	sbi_exit(scratch);

lib/utils/reset/fdt_reset.c

@@ -23,20 +23,6 @@ static struct fdt_reset *reset_drivers[] = {
 
 static struct fdt_reset *current_driver = NULL;
 
-int fdt_system_reset_check(u32 reset_type, u32 reset_reason)
-{
-	if (current_driver && current_driver->system_reset_check)
-		return current_driver->system_reset_check(reset_type,
-							  reset_reason);
-	return 0;
-}
-
-void fdt_system_reset(u32 reset_type, u32 reset_reason)
-{
-	if (current_driver && current_driver->system_reset)
-		current_driver->system_reset(reset_type, reset_reason);
-}
-
 int fdt_reset_init(void)
 {
 	int pos, noff, rc;

lib/utils/reset/fdt_reset_htif.c

@@ -11,6 +11,12 @@
 #include <sbi_utils/fdt/fdt_helper.h>
 #include <sbi_utils/sys/htif.h>
 
+static int htif_reset_init(void *fdt, int nodeoff,
+			   const struct fdt_match *match)
+{
+	return htif_system_reset_init();
+}
+
 static const struct fdt_match htif_reset_match[] = {
 	{ .compatible = "ucb,htif0" },
 	{ },
@@ -18,6 +24,5 @@ static const struct fdt_match htif_reset_match[] = {
 
 struct fdt_reset fdt_reset_htif = {
 	.match_table = htif_reset_match,
-	.system_reset_check = htif_system_reset_check,
-	.system_reset = htif_system_reset
+	.init = htif_reset_init
 };

lib/utils/reset/fdt_reset_sifive.c

@@ -33,6 +33,4 @@ static const struct fdt_match sifive_test_reset_match[] = {
 struct fdt_reset fdt_reset_sifive = {
 	.match_table = sifive_test_reset_match,
 	.init = sifive_test_reset_init,
-	.system_reset_check = sifive_test_system_reset_check,
-	.system_reset = sifive_test_system_reset
 };

lib/utils/reset/fdt_reset_thead.c

@@ -7,8 +7,10 @@
 #include <sbi/sbi_bitops.h>
 #include <sbi/sbi_hart.h>
 #include <sbi/sbi_scratch.h>
+#include <sbi/sbi_system.h>
 #include <sbi_utils/fdt/fdt_helper.h>
 #include <sbi_utils/reset/fdt_reset.h>
+
 #include "fdt_reset_thead.h"
 
 struct custom_csr custom_csr[MAX_CUSTOM_CSR];
@@ -37,6 +39,22 @@ static void clone_csrs(int cnt)
 	}
 }
 
+static int thead_system_reset_check(u32 type, u32 reason)
+{
+	return 1;
+}
+
+static void thead_system_reset(u32 type, u32 reason)
+{
+	ebreak();
+}
+
+static struct sbi_system_reset_device thead_reset = {
+	.name = "thead_reset",
+	.system_reset_check = thead_system_reset_check,
+	.system_reset = thead_system_reset
+};
+
 extern void __thead_pre_start_warm(void);
 static int thead_reset_init(void *fdt, int nodeoff,
 				 const struct fdt_match *match)
@@ -106,19 +124,11 @@ static int thead_reset_init(void *fdt, int nodeoff,
 		}
 	}
 
+	sbi_system_reset_set_device(&thead_reset);
+
 	return 0;
 }
 
-int thead_system_reset_check(u32 type, u32 reason)
-{
-	return 1;
-}
-
-void thead_system_reset(u32 type, u32 reason)
-{
-	ebreak();
-}
-
 static const struct fdt_match thead_reset_match[] = {
 	{ .compatible = "thead,reset-sample" },
 	{ },
@@ -126,7 +136,5 @@ static const struct fdt_match thead_reset_match[] = {
 
 struct fdt_reset fdt_reset_thead = {
 	.match_table = thead_reset_match,
-	.init = thead_reset_init,
-	.system_reset_check = thead_system_reset_check,
-	.system_reset = thead_system_reset
+	.init = thead_reset_init
 };

lib/utils/sys/htif.c

@@ -7,6 +7,7 @@
 
 #include <sbi/riscv_locks.h>
 #include <sbi/sbi_console.h>
+#include <sbi/sbi_system.h>
 #include <sbi_utils/sys/htif.h>
 
 #define HTIF_DATA_BITS		48
@@ -154,15 +155,28 @@ int htif_serial_init(void)
 	return 0;
 }
 
-int htif_system_reset_check(u32 type, u32 reason)
+static int htif_system_reset_check(u32 type, u32 reason)
 {
 	return 1;
 }
 
-void htif_system_reset(u32 type, u32 reason)
+static void htif_system_reset(u32 type, u32 reason)
 {
 	while (1) {
 		fromhost = 0;
 		tohost = 1;
 	}
 }
+
+static struct sbi_system_reset_device htif_reset = {
+	.name = "htif",
+	.system_reset_check = htif_system_reset_check,
+	.system_reset = htif_system_reset
+};
+
+int htif_system_reset_init(void)
+{
+	sbi_system_reset_set_device(&htif_reset);
+
+	return 0;
+}

lib/utils/sys/sifive_test.c

@@ -9,6 +9,7 @@
 
 #include <sbi/riscv_io.h>
 #include <sbi/sbi_ecall_interface.h>
+#include <sbi/sbi_system.h>
 #include <sbi_utils/sys/sifive_test.h>
 
 #define FINISHER_FAIL		0x3333
@@ -17,7 +18,7 @@
 
 static void *sifive_test_base;
 
-int sifive_test_system_reset_check(u32 type, u32 reason)
+static int sifive_test_system_reset_check(u32 type, u32 reason)
 {
 	switch (type) {
 	case SBI_SRST_RESET_TYPE_SHUTDOWN:
@@ -29,7 +30,7 @@ int sifive_test_system_reset_check(u32 type, u32 reason)
 	return 0;
 }
 
-void sifive_test_system_reset(u32 type, u32 reason)
+static void sifive_test_system_reset(u32 type, u32 reason)
 {
 	/*
 	 * Tell the "finisher" that the simulation
@@ -49,9 +50,16 @@ void sifive_test_system_reset(u32 type, u32 reason)
 	}
 }
 
+static struct sbi_system_reset_device sifive_test_reset = {
+	.name = "sifive_test",
+	.system_reset_check = sifive_test_system_reset_check,
+	.system_reset = sifive_test_system_reset
+};
+
 int sifive_test_init(unsigned long base)
 {
 	sifive_test_base = (void *)base;
+	sbi_system_reset_set_device(&sifive_test_reset);
 
 	return 0;
 }