Hi Anup, Le 5/25/20 à 2:21 AM, Anup Patel a écrit :
On Sun, May 24, 2020 at 2:47 PM Alexandre Ghiti <a...@ghiti.fr> wrote:Now that the mmu type is determined at runtime using SATP characteristic, use the global variable pgtable_l4_enabled to output mmu type of the processor through /proc/cpuinfo instead of relying on device tree infos.Signed-off-by: Alexandre Ghiti <a...@ghiti.fr> Reviewed-by: Anup Patel <a...@brainfault.org> Reviewed-by: Palmer Dabbelt <palmerdabb...@google.com> --- arch/riscv/boot/dts/sifive/fu540-c000.dtsi | 4 ---- arch/riscv/kernel/cpu.c | 24 ++++++++++++---------- 2 files changed, 13 insertions(+), 15 deletions(-) diff --git a/arch/riscv/boot/dts/sifive/fu540-c000.dtsi b/arch/riscv/boot/dts/sifive/fu540-c000.dtsi index 7db861053483..6138590a2229 100644 --- a/arch/riscv/boot/dts/sifive/fu540-c000.dtsi +++ b/arch/riscv/boot/dts/sifive/fu540-c000.dtsi @@ -50,7 +50,6 @@ i-cache-size = <32768>; i-tlb-sets = <1>; i-tlb-size = <32>; - mmu-type = "riscv,sv39"; reg = <1>; riscv,isa = "rv64imafdc"; tlb-split; @@ -74,7 +73,6 @@ i-cache-size = <32768>; i-tlb-sets = <1>; i-tlb-size = <32>; - mmu-type = "riscv,sv39"; reg = <2>; riscv,isa = "rv64imafdc"; tlb-split; @@ -98,7 +96,6 @@ i-cache-size = <32768>; i-tlb-sets = <1>; i-tlb-size = <32>; - mmu-type = "riscv,sv39"; reg = <3>; riscv,isa = "rv64imafdc"; tlb-split; @@ -122,7 +119,6 @@ i-cache-size = <32768>; i-tlb-sets = <1>; i-tlb-size = <32>; - mmu-type = "riscv,sv39"; reg = <4>; riscv,isa = "rv64imafdc"; tlb-split;Your PATCH6 is already doing the right thing by skipping CPU DT nodes that don't have "mmu-type" DT property. The "mmu-type" DT property is very critical for RUNTIME M-mode firmware (OpenSBI) because it tells whether a given CPU has MMU (or not). This is also in agreement with the current DT bindings document for RISC-V CPUs. I suggest to drop the change in sifive/fu540-c000.dtsi and rest of the patch is fine so my Reviewed-by still holds.
Ok I'll do that in v2, thanks. Alex
Regards, Anupdiff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index 40a3c442ac5f..38a699b997a8 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -8,6 +8,8 @@ #include <linux/of.h> #include <asm/smp.h> +extern bool pgtable_l4_enabled; + /* * Returns the hart ID of the given device tree node, or -ENODEV if the node * isn't an enabled and valid RISC-V hart node. @@ -54,18 +56,19 @@ static void print_isa(struct seq_file *f, const char *isa) seq_puts(f, "\n"); } -static void print_mmu(struct seq_file *f, const char *mmu_type) +static void print_mmu(struct seq_file *f) { + char sv_type[16]; + #if defined(CONFIG_32BIT) - if (strcmp(mmu_type, "riscv,sv32") != 0) - return; + strncpy(sv_type, "sv32", 5); #elif defined(CONFIG_64BIT) - if (strcmp(mmu_type, "riscv,sv39") != 0 && - strcmp(mmu_type, "riscv,sv48") != 0) - return; + if (pgtable_l4_enabled) + strncpy(sv_type, "sv48", 5); + else + strncpy(sv_type, "sv39", 5); #endif - - seq_printf(f, "mmu\t\t: %s\n", mmu_type+6); + seq_printf(f, "mmu\t\t: %s\n", sv_type); } static void *c_start(struct seq_file *m, loff_t *pos) @@ -90,14 +93,13 @@ static int c_show(struct seq_file *m, void *v) { unsigned long cpu_id = (unsigned long)v - 1; struct device_node *node = of_get_cpu_node(cpu_id, NULL); - const char *compat, *isa, *mmu; + const char *compat, *isa; seq_printf(m, "processor\t: %lu\n", cpu_id); seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id)); if (!of_property_read_string(node, "riscv,isa", &isa)) print_isa(m, isa); - if (!of_property_read_string(node, "mmu-type", &mmu)) - print_mmu(m, mmu); + print_mmu(m); if (!of_property_read_string(node, "compatible", &compat) && strcmp(compat, "riscv")) seq_printf(m, "uarch\t\t: %s\n", compat); -- 2.20.1
