[RFC PATCH v2 7/9] lib: utils/irqchip: Add FDT wrappers for PLIC save/restore functions

[Samuel Holland]

These functions save/restore the state of the PLIC associated with the
current hart. Only the S-mode context is saved/restored, under the
assumption that none of the interrupts are enabled in M-mode anyway.

Signed-off-by: Samuel Holland <samuel at sholland.org>
---

Changes in v2:
 - New patch for v2

 include/sbi_utils/irqchip/fdt_irqchip_plic.h | 20 ++++++++++++
 lib/utils/irqchip/fdt_irqchip_plic.c         | 32 ++++++++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 include/sbi_utils/irqchip/fdt_irqchip_plic.h

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..66650a2
--- /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 at sholland.org>
+ */
+
+#ifndef __IRQCHIP_FDT_IRQCHIP_PLIC_H__
+#define __IRQCHIP_FDT_IRQCHIP_PLIC_H__
+
+#include <sbi/sbi_types.h>
+
+void irqchip_plic_priority_save(u8 *priority);
+
+void irqchip_plic_priority_restore(const u8 *priority);
+
+void irqchip_plic_context_save(u32 *enable, u32 *threshold);
+
+void irqchip_plic_context_restore(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..37090d3 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 irqchip_plic_priority_save(u8 *priority)
+{
+	struct plic_data *plic = plic_hartid2data[current_hartid()];
+
+	plic_priority_save(plic, priority);
+}
+
+void irqchip_plic_priority_restore(const u8 *priority)
+{
+	struct plic_data *plic = plic_hartid2data[current_hartid()];
+
+	plic_priority_restore(plic, priority);
+}
+
+void irqchip_plic_context_save(u32 *enable, u32 *threshold)
+{
+	u32 hartid = current_hartid();
+
+	plic_context_save(plic_hartid2data[hartid],
+			  plic_hartid2context[hartid][1],
+			  enable, threshold);
+}
+
+void irqchip_plic_context_restore(const u32 *enable, u32 threshold)
+{
+	u32 hartid = current_hartid();
+
+	plic_context_restore(plic_hartid2data[hartid],
+			     plic_hartid2context[hartid][1],
+			     enable, threshold);
+}
+
 static int irqchip_plic_warm_init(void)
 {
 	u32 hartid = current_hartid();
-- 
2.35.1