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-rw-r--r--arch/riscv/kernel/pi/Makefile2
-rw-r--r--arch/riscv/kernel/pi/cmdline_early.c4
-rw-r--r--arch/riscv/kernel/pi/fdt_early.c40
-rw-r--r--arch/riscv/kernel/pi/pi.h1
4 files changed, 44 insertions, 3 deletions
diff --git a/arch/riscv/kernel/pi/Makefile b/arch/riscv/kernel/pi/Makefile
index 7dd15be69c90..bc098edac898 100644
--- a/arch/riscv/kernel/pi/Makefile
+++ b/arch/riscv/kernel/pi/Makefile
@@ -39,4 +39,4 @@ $(obj)/ctype.o: $(srctree)/lib/ctype.c FORCE
$(call if_changed_rule,cc_o_c)
obj-y := cmdline_early.pi.o fdt_early.pi.o string.pi.o ctype.pi.o lib-fdt.pi.o lib-fdt_ro.pi.o archrandom_early.pi.o
-extra-y := $(patsubst %.pi.o,%.o,$(obj-y))
+targets := $(patsubst %.pi.o,%.o,$(obj-y))
diff --git a/arch/riscv/kernel/pi/cmdline_early.c b/arch/riscv/kernel/pi/cmdline_early.c
index fbcdc9e4e143..389d086a0718 100644
--- a/arch/riscv/kernel/pi/cmdline_early.c
+++ b/arch/riscv/kernel/pi/cmdline_early.c
@@ -41,9 +41,9 @@ static char *get_early_cmdline(uintptr_t dtb_pa)
static u64 match_noXlvl(char *cmdline)
{
if (strstr(cmdline, "no4lvl"))
- return SATP_MODE_48;
+ return SATP_MODE_39;
else if (strstr(cmdline, "no5lvl"))
- return SATP_MODE_57;
+ return SATP_MODE_48;
return 0;
}
diff --git a/arch/riscv/kernel/pi/fdt_early.c b/arch/riscv/kernel/pi/fdt_early.c
index 9bdee2fafe47..a12ff8090f19 100644
--- a/arch/riscv/kernel/pi/fdt_early.c
+++ b/arch/riscv/kernel/pi/fdt_early.c
@@ -3,6 +3,7 @@
#include <linux/init.h>
#include <linux/libfdt.h>
#include <linux/ctype.h>
+#include <asm/csr.h>
#include "pi.h"
@@ -183,3 +184,42 @@ bool fdt_early_match_extension_isa(const void *fdt, const char *ext_name)
return ret;
}
+
+/**
+ * set_satp_mode_from_fdt - determine SATP mode based on the MMU type in fdt
+ *
+ * @dtb_pa: physical address of the device tree blob
+ *
+ * Returns the SATP mode corresponding to the MMU type of the first enabled CPU,
+ * 0 otherwise
+ */
+u64 set_satp_mode_from_fdt(uintptr_t dtb_pa)
+{
+ const void *fdt = (const void *)dtb_pa;
+ const char *mmu_type;
+ int node, parent;
+
+ parent = fdt_path_offset(fdt, "/cpus");
+ if (parent < 0)
+ return 0;
+
+ fdt_for_each_subnode(node, fdt, parent) {
+ if (!fdt_node_name_eq(fdt, node, "cpu"))
+ continue;
+
+ if (!fdt_device_is_available(fdt, node))
+ continue;
+
+ mmu_type = fdt_getprop(fdt, node, "mmu-type", NULL);
+ if (!mmu_type)
+ break;
+
+ if (!strcmp(mmu_type, "riscv,sv39"))
+ return SATP_MODE_39;
+ else if (!strcmp(mmu_type, "riscv,sv48"))
+ return SATP_MODE_48;
+ break;
+ }
+
+ return 0;
+}
diff --git a/arch/riscv/kernel/pi/pi.h b/arch/riscv/kernel/pi/pi.h
index 21141d84fea6..3fee2cfddf7c 100644
--- a/arch/riscv/kernel/pi/pi.h
+++ b/arch/riscv/kernel/pi/pi.h
@@ -14,6 +14,7 @@ u64 get_kaslr_seed(uintptr_t dtb_pa);
u64 get_kaslr_seed_zkr(const uintptr_t dtb_pa);
bool set_nokaslr_from_cmdline(uintptr_t dtb_pa);
u64 set_satp_mode_from_cmdline(uintptr_t dtb_pa);
+u64 set_satp_mode_from_fdt(uintptr_t dtb_pa);
bool fdt_early_match_extension_isa(const void *fdt, const char *ext_name);