lib: utils/irqchip: Add FDT wrappers for PLIC save/restore functions

These functions save/restore the state of the PLIC associated with the
current hart. The context save/restore functions only manipulate a
single context, since most likely the M-mode context is unused and does
not need to be saved.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Anup Patel <anup@brainfault.org>

2 files changed, 52 insertions, 0 deletions

diff --git a/include/sbi_utils/irqchip/fdt_irqchip_plic.h b/include/sbi_utils/irqchip/fdt_irqchip_plic.h
new file mode 100644
index 0000000..f158b02
--- /dev/null
+++ b/include/sbi_utils/irqchip/fdt_irqchip_plic.h
@@ -0,0 +1,20 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2022 Samuel Holland <samuel@sholland.org>
+ */
+
+#ifndef __IRQCHIP_FDT_IRQCHIP_PLIC_H__
+#define __IRQCHIP_FDT_IRQCHIP_PLIC_H__
+
+#include <sbi/sbi_types.h>
+
+void fdt_plic_priority_save(u8 *priority);
+
+void fdt_plic_priority_restore(const u8 *priority);
+
+void fdt_plic_context_save(bool smode, u32 *enable, u32 *threshold);
+
+void fdt_plic_context_restore(bool smode, const u32 *enable, u32 threshold);
+
+#endif
diff --git a/lib/utils/irqchip/fdt_irqchip_plic.c b/lib/utils/irqchip/fdt_irqchip_plic.c
index b2d2a1b..89b12d4 100644
--- a/lib/utils/irqchip/fdt_irqchip_plic.c
+++ b/lib/utils/irqchip/fdt_irqchip_plic.c
@@ -24,6 +24,38 @@ static struct plic_data plic[PLIC_MAX_NR];
 static struct plic_data *plic_hartid2data[SBI_HARTMASK_MAX_BITS];
 static int plic_hartid2context[SBI_HARTMASK_MAX_BITS][2];
 
+void fdt_plic_priority_save(u8 *priority)
+{
+	struct plic_data *plic = plic_hartid2data[current_hartid()];
+
+	plic_priority_save(plic, priority);
+}
+
+void fdt_plic_priority_restore(const u8 *priority)
+{
+	struct plic_data *plic = plic_hartid2data[current_hartid()];
+
+	plic_priority_restore(plic, priority);
+}
+
+void fdt_plic_context_save(bool smode, u32 *enable, u32 *threshold)
+{
+	u32 hartid = current_hartid();
+
+	plic_context_save(plic_hartid2data[hartid],
+			  plic_hartid2context[hartid][smode],
+			  enable, threshold);
+}
+
+void fdt_plic_context_restore(bool smode, const u32 *enable, u32 threshold)
+{
+	u32 hartid = current_hartid();
+
+	plic_context_restore(plic_hartid2data[hartid],
+			     plic_hartid2context[hartid][smode],
+			     enable, threshold);
+}
+
 static int irqchip_plic_warm_init(void)
 {
 	u32 hartid = current_hartid();