Messages in this thread Patch in this message | | | From | Anup Patel <> | Subject | [PATCH 3/3] RISC-V: Access CSRs using CSR numbers | Date | Sat, 13 Apr 2019 07:39:44 +0000 |
| |
We should prefer accessing CSRs using their CSR numbers because: 1. It compiles fine with older toolchains. 2. We can use latest CSR names in #define macro names of CSR numbers as-per RISC-V spec. 3. We can access newly added CSRs even if toolchain does not recognize newly addes CSRs by name.
Signed-off-by: Anup Patel <anup.patel@wdc.com> --- arch/riscv/include/asm/csr.h | 15 ++++++++------- arch/riscv/include/asm/irqflags.h | 10 +++++----- arch/riscv/include/asm/mmu_context.h | 2 +- arch/riscv/kernel/entry.S | 22 +++++++++++----------- arch/riscv/kernel/head.S | 12 ++++++------ arch/riscv/kernel/perf_event.c | 4 ++-- arch/riscv/kernel/smp.c | 2 +- arch/riscv/kernel/traps.c | 6 +++--- arch/riscv/mm/fault.c | 2 +- 9 files changed, 38 insertions(+), 37 deletions(-)
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h index 8cf698e39463..6bf5652d3565 100644 --- a/arch/riscv/include/asm/csr.h +++ b/arch/riscv/include/asm/csr.h @@ -14,6 +14,7 @@ #ifndef _ASM_RISCV_CSR_H #define _ASM_RISCV_CSR_H
+#include <asm/asm.h> #include <asm/encoding.h>
#ifndef __ASSEMBLY__ @@ -21,7 +22,7 @@ #define csr_swap(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrrw %0, " #csr ", %1" \ + __asm__ __volatile__ ("csrrw %0, " __ASM_STR(csr) ", %1"\ : "=r" (__v) : "rK" (__v) \ : "memory"); \ __v; \ @@ -30,7 +31,7 @@ #define csr_read(csr) \ ({ \ register unsigned long __v; \ - __asm__ __volatile__ ("csrr %0, " #csr \ + __asm__ __volatile__ ("csrr %0, " __ASM_STR(csr) \ : "=r" (__v) : \ : "memory"); \ __v; \ @@ -39,7 +40,7 @@ #define csr_write(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrw " #csr ", %0" \ + __asm__ __volatile__ ("csrw " __ASM_STR(csr) ", %0" \ : : "rK" (__v) \ : "memory"); \ }) @@ -47,7 +48,7 @@ #define csr_read_set(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrrs %0, " #csr ", %1" \ + __asm__ __volatile__ ("csrrs %0, " __ASM_STR(csr) ", %1"\ : "=r" (__v) : "rK" (__v) \ : "memory"); \ __v; \ @@ -56,7 +57,7 @@ #define csr_set(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrs " #csr ", %0" \ + __asm__ __volatile__ ("csrs " __ASM_STR(csr) ", %0" \ : : "rK" (__v) \ : "memory"); \ }) @@ -64,7 +65,7 @@ #define csr_read_clear(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrrc %0, " #csr ", %1" \ + __asm__ __volatile__ ("csrrc %0, " __ASM_STR(csr) ", %1"\ : "=r" (__v) : "rK" (__v) \ : "memory"); \ __v; \ @@ -73,7 +74,7 @@ #define csr_clear(csr, val) \ ({ \ unsigned long __v = (unsigned long)(val); \ - __asm__ __volatile__ ("csrc " #csr ", %0" \ + __asm__ __volatile__ ("csrc " __ASM_STR(csr) ", %0" \ : : "rK" (__v) \ : "memory"); \ }) diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h index 07a3c6d5706f..1a69b3bcd371 100644 --- a/arch/riscv/include/asm/irqflags.h +++ b/arch/riscv/include/asm/irqflags.h @@ -21,25 +21,25 @@ /* read interrupt enabled status */ static inline unsigned long arch_local_save_flags(void) { - return csr_read(sstatus); + return csr_read(CSR_SSTATUS); }
/* unconditionally enable interrupts */ static inline void arch_local_irq_enable(void) { - csr_set(sstatus, SR_SIE); + csr_set(CSR_SSTATUS, SR_SIE); }
/* unconditionally disable interrupts */ static inline void arch_local_irq_disable(void) { - csr_clear(sstatus, SR_SIE); + csr_clear(CSR_SSTATUS, SR_SIE); }
/* get status and disable interrupts */ static inline unsigned long arch_local_irq_save(void) { - return csr_read_clear(sstatus, SR_SIE); + return csr_read_clear(CSR_SSTATUS, SR_SIE); }
/* test flags */ @@ -57,7 +57,7 @@ static inline int arch_irqs_disabled(void) /* set interrupt enabled status */ static inline void arch_local_irq_restore(unsigned long flags) { - csr_set(sstatus, flags & SR_SIE); + csr_set(CSR_SSTATUS, flags & SR_SIE); }
#endif /* _ASM_RISCV_IRQFLAGS_H */ diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h index 336d60ec5698..42094c3f80d6 100644 --- a/arch/riscv/include/asm/mmu_context.h +++ b/arch/riscv/include/asm/mmu_context.h @@ -88,7 +88,7 @@ static inline void switch_mm(struct mm_struct *prev, * name to support binutils 2.29 which doesn't know about the * privileged ISA 1.10 yet. */ - csr_write(sptbr, virt_to_pfn(next->pgd) | SATP_MODE); + csr_write(CSR_SATP, virt_to_pfn(next->pgd) | SATP_MODE); local_flush_tlb_all();
flush_icache_deferred(next); diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index fd9b57c8b4ce..1c1ecc238cfa 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -37,11 +37,11 @@ * the kernel thread pointer. If we came from the kernel, sscratch * will contain 0, and we should continue on the current TP. */ - csrrw tp, sscratch, tp + csrrw tp, CSR_SSCRATCH, tp bnez tp, _save_context
_restore_kernel_tpsp: - csrr tp, sscratch + csrr tp, CSR_SSCRATCH REG_S sp, TASK_TI_KERNEL_SP(tp) _save_context: REG_S sp, TASK_TI_USER_SP(tp) @@ -87,11 +87,11 @@ _save_context: li t0, SR_SUM | SR_FS
REG_L s0, TASK_TI_USER_SP(tp) - csrrc s1, sstatus, t0 - csrr s2, sepc - csrr s3, sbadaddr - csrr s4, scause - csrr s5, sscratch + csrrc s1, CSR_SSTATUS, t0 + csrr s2, CSR_SEPC + csrr s3, CSR_STVAL + csrr s4, CSR_SCAUSE + csrr s5, CSR_SSCRATCH REG_S s0, PT_SP(sp) REG_S s1, PT_SSTATUS(sp) REG_S s2, PT_SEPC(sp) @@ -107,8 +107,8 @@ _save_context: .macro RESTORE_ALL REG_L a0, PT_SSTATUS(sp) REG_L a2, PT_SEPC(sp) - csrw sstatus, a0 - csrw sepc, a2 + csrw CSR_SSTATUS, a0 + csrw CSR_SEPC, a2
REG_L x1, PT_RA(sp) REG_L x3, PT_GP(sp) @@ -155,7 +155,7 @@ ENTRY(handle_exception) * Set sscratch register to 0, so that if a recursive exception * occurs, the exception vector knows it came from the kernel */ - csrw sscratch, x0 + csrw CSR_SSCRATCH, x0
/* Load the global pointer */ .option push @@ -248,7 +248,7 @@ resume_userspace: * Save TP into sscratch, so we can find the kernel data structures * again. */ - csrw sscratch, tp + csrw CSR_SSCRATCH, tp
restore_all: RESTORE_ALL diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index fe884cd69abd..041492636b45 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -23,7 +23,7 @@ __INIT ENTRY(_start) /* Mask all interrupts */ - csrw sie, zero + csrw CSR_SIE, zero
/* Load the global pointer */ .option push @@ -89,7 +89,7 @@ relocate: /* Point stvec to virtual address of intruction after satp write */ la a0, 1f add a0, a0, a1 - csrw stvec, a0 + csrw CSR_STVEC, a0
/* Compute satp for kernel page tables, but don't load it yet */ la a2, swapper_pg_dir @@ -105,12 +105,12 @@ relocate: srl a0, a0, PAGE_SHIFT or a0, a0, a1 sfence.vma - csrw sptbr, a0 + csrw CSR_SATP, a0 .align 2 1: /* Set trap vector to spin forever to help debug */ la a0, .Lsecondary_park - csrw stvec, a0 + csrw CSR_STVEC, a0
/* Reload the global pointer */ .option push @@ -119,7 +119,7 @@ relocate: .option pop
/* Switch to kernel page tables */ - csrw sptbr, a2 + csrw CSR_SATP, a2
ret
@@ -130,7 +130,7 @@ relocate:
/* Set trap vector to spin forever to help debug */ la a3, .Lsecondary_park - csrw stvec, a3 + csrw CSR_STVEC, a3
slli a3, a0, LGREG la a1, __cpu_up_stack_pointer diff --git a/arch/riscv/kernel/perf_event.c b/arch/riscv/kernel/perf_event.c index 667ee70defea..91626d9ae5f2 100644 --- a/arch/riscv/kernel/perf_event.c +++ b/arch/riscv/kernel/perf_event.c @@ -185,10 +185,10 @@ static inline u64 read_counter(int idx)
switch (idx) { case RISCV_PMU_CYCLE: - val = csr_read(cycle); + val = csr_read(CSR_CYCLE); break; case RISCV_PMU_INSTRET: - val = csr_read(instret); + val = csr_read(CSR_INSTRET); break; default: WARN_ON_ONCE(idx < 0 || idx > RISCV_MAX_COUNTERS); diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c index 0c41d07ec281..f244c63d29e4 100644 --- a/arch/riscv/kernel/smp.c +++ b/arch/riscv/kernel/smp.c @@ -89,7 +89,7 @@ void riscv_software_interrupt(void) unsigned long *stats = ipi_data[smp_processor_id()].stats;
/* Clear pending IPI */ - csr_clear(sip, SIE_SSIE); + csr_clear(CSR_SIP, SIE_SSIE);
while (true) { unsigned long ops; diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 24a9333dda2c..1b407a9db3fc 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -159,9 +159,9 @@ void __init trap_init(void) * Set sup0 scratch register to 0, indicating to exception vector * that we are presently executing in the kernel */ - csr_write(sscratch, 0); + csr_write(CSR_SSCRATCH, 0); /* Set the exception vector address */ - csr_write(stvec, &handle_exception); + csr_write(CSR_STVEC, &handle_exception); /* Enable all interrupts */ - csr_write(sie, -1); + csr_write(CSR_SIE, -1); } diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index 88401d5125bc..bb0461ed7efc 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -245,7 +245,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs) * the privileged ISA 1.10 yet. */ index = pgd_index(addr); - pgd = (pgd_t *)pfn_to_virt(csr_read(sptbr)) + index; + pgd = (pgd_t *)pfn_to_virt(csr_read(CSR_SATP)) + index; pgd_k = init_mm.pgd + index;
if (!pgd_present(*pgd_k)) -- 2.17.1 | |