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/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _ASM_RISCV_CSR_INDIRECT_H
#define _ASM_RISCV_CSR_INDIRECT_H
#include <linux/irqflags.h>
#include <asm/csr.h>
/*
* These have to be macros rather than functions: csr_read()/csr_write()
* stringify their CSR argument into the inline asm template via __ASM_STR(),
* so the CSR number must be a literal token at preprocessing time. Passing it
* as a function parameter emits "csrr %0, iregcsr", which no assembler can
* resolve. RISC-V has no register-indirect form of csrr/csrw - the CSR is a
* 12-bit immediate - so the sireg CSR selecting the indirect window cannot
* itself be a variable.
*/
#define csr_indirect_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_indirect_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_indirect_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, (warl_val)); \
__value = csr_read(iregcsr); \
csr_write(iregcsr, __old_val); \
local_irq_restore(__flags); \
__value; \
})
#endif
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