The indriect CSR requires multiple instructions to read/write CSR.
Add a few helper functions for ease of usage.
Signed-off-by: Atish Patra <atishp@xxxxxxxxxxxx>
---
arch/riscv/include/asm/csr_ind.h | 42 ++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)
create mode 100644 arch/riscv/include/asm/csr_ind.h
diff --git a/arch/riscv/include/asm/csr_ind.h b/arch/riscv/include/asm/csr_ind.h
new file mode 100644
index 000000000000..9611c221eb6f
--- /dev/null
+++ b/arch/riscv/include/asm/csr_ind.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2024 Rivos Inc.
+ */
+
+#ifndef _ASM_RISCV_CSR_IND_H
+#define _ASM_RISCV_CSR_IND_H
+
+#include <asm/csr.h>
+
+#define csr_ind_read(iregcsr, iselbase, iseloff) ({ \
+ unsigned long value = 0; \
+ unsigned long flags; \
+ local_irq_save(flags); \
+ csr_write(CSR_ISELECT, iselbase + iseloff); \
+ value = csr_read(iregcsr); \
+ local_irq_restore(flags); \
+ value; \
+})
+
+#define csr_ind_write(iregcsr, iselbase, iseloff, value) ({ \
+ unsigned long flags; \
+ local_irq_save(flags); \
+ csr_write(CSR_ISELECT, iselbase + iseloff); \
+ csr_write(iregcsr, value); \
+ local_irq_restore(flags); \
+})
+
+#define csr_ind_warl(iregcsr, iselbase, iseloff, warl_val) ({ \
+ unsigned long old_val = 0, value = 0; \
+ unsigned long flags; \
+ local_irq_save(flags); \
+ csr_write(CSR_ISELECT, iselbase + iseloff); \
+ old_val = csr_read(iregcsr); \
+ csr_write(iregcsr, value); \
+ value = csr_read(iregcsr); \
+ csr_write(iregcsr, old_val); \
+ local_irq_restore(flags); \
+ value; \
+})
+
+#endif
--
2.34.1
