[PATCH v4 02/11] RISC-V: don't parse dt/acpi isa string to get rv32/rv64

Conor Dooley conor.dooley at microchip.com
Mon Jul 10 02:35:37 PDT 2023


From: Heiko Stuebner <heiko.stuebner at vrull.eu>

When filling hwcap the kernel already expects the isa string to start with
rv32 if CONFIG_32BIT and rv64 if CONFIG_64BIT.

So when recreating the runtime isa-string we can also just go the other way
to get the correct starting point for it.

Signed-off-by: Heiko Stuebner <heiko.stuebner at vrull.eu>
Reviewed-by: Andrew Jones <ajones at ventanamicro.com>
Reviewed-by: Evan Green <evan at rivosinc.com>
Co-developed-by: Conor Dooley <conor.dooley at microchip.com>
Signed-off-by: Conor Dooley <conor.dooley at microchip.com>
---
Changes in v3:
- Fix tabbing of print_mmu()

Changes in v2:
- Delete the whole else & pull print_mmu() above it, since that's common
  code now
---
 arch/riscv/kernel/cpu.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index 3af2d214ce21..f808b67f5a27 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -257,13 +257,16 @@ static void print_isa_ext(struct seq_file *f)
  */
 static const char base_riscv_exts[13] = "imafdqcbkjpvh";
 
-static void print_isa(struct seq_file *f, const char *isa)
+static void print_isa(struct seq_file *f)
 {
 	int i;
 
 	seq_puts(f, "isa\t\t: ");
-	/* Print the rv[64/32] part */
-	seq_write(f, isa, 4);
+	if (IS_ENABLED(CONFIG_32BIT))
+		seq_write(f, "rv32", 4);
+	else
+		seq_write(f, "rv64", 4);
+
 	for (i = 0; i < sizeof(base_riscv_exts); i++) {
 		if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a'))
 			/* Print only enabled the base ISA extensions */
@@ -320,27 +323,21 @@ static int c_show(struct seq_file *m, void *v)
 	unsigned long cpu_id = (unsigned long)v - 1;
 	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
 	struct device_node *node;
-	const char *compat, *isa;
+	const char *compat;
 
 	seq_printf(m, "processor\t: %lu\n", cpu_id);
 	seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id));
+	print_isa(m);
+	print_mmu(m);
 
 	if (acpi_disabled) {
 		node = of_get_cpu_node(cpu_id, NULL);
-		if (!of_property_read_string(node, "riscv,isa", &isa))
-			print_isa(m, isa);
 
-		print_mmu(m);
 		if (!of_property_read_string(node, "compatible", &compat) &&
 		    strcmp(compat, "riscv"))
 			seq_printf(m, "uarch\t\t: %s\n", compat);
 
 		of_node_put(node);
-	} else {
-		if (!acpi_get_riscv_isa(NULL, cpu_id, &isa))
-			print_isa(m, isa);
-
-		print_mmu(m);
 	}
 
 	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
-- 
2.40.1




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