Merge tag 'riscv-for-linus-6.18-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Paul Walmsley

 - Replacement of __ASSEMBLY__ with __ASSEMBLER__ in header files (other
   architectures have already merged this type of cleanup)

 - The introduction of ioremap_wc() for RISC-V

 - Cleanup of the RISC-V kprobes code to use mostly-extant macros rather
   than open code

 - A RISC-V kprobes unit test

 - An architecture-specific endianness swap macro set implementation,
   leveraging some dedicated RISC-V instructions for this purpose if
   they are available

 - The ability to identity and communicate to userspace the presence
   of a MIPS P8700-specific ISA extension, and to leverage its
   MIPS-specific PAUSE implementation in cpu_relax()

 - Several other miscellaneous cleanups

* tag 'riscv-for-linus-6.18-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (39 commits)
  riscv: errata: Fix the PAUSE Opcode for MIPS P8700
  riscv: hwprobe: Document MIPS xmipsexectl vendor extension
  riscv: hwprobe: Add MIPS vendor extension probing
  riscv: Add xmipsexectl instructions
  riscv: Add xmipsexectl as a vendor extension
  dt-bindings: riscv: Add xmipsexectl ISA extension description
  riscv: cpufeature: add validation for zfa, zfh and zfhmin
  perf: riscv: skip empty batches in counter start
  selftests: riscv: Add README for RISC-V KSelfTest
  riscv: sbi: Switch to new sys-off handler API
  riscv: Move vendor errata definitions to new header
  RISC-V: ACPI: enable parsing the BGRT table
  riscv: Enable ARCH_HAVE_NMI_SAFE_CMPXCHG
  riscv: pi: use 'targets' instead of extra-y in Makefile
  riscv: introduce asm/swab.h
  riscv: mmap(): use unsigned offset type in riscv_sys_mmap
  drivers/perf: riscv: Remove redundant ternary operators
  riscv: mm: Use mmu-type from FDT to limit SATP mode
  riscv: mm: Return intended SATP mode for noXlvl options
  riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM
  ...

1 files changed, 9 insertions, 3 deletions

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 15683ae13fa5..6091f3f06fa3 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -23,6 +23,7 @@
 #include <linux/kfence.h>
 #include <linux/execmem.h>
 
+#include <asm/alternative.h>
 #include <asm/fixmap.h>
 #include <asm/io.h>
 #include <asm/kasan.h>
@@ -816,6 +817,7 @@ static __meminit pgprot_t pgprot_from_va(uintptr_t va)
 
 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
+u64 __pi_set_satp_mode_from_fdt(uintptr_t dtb_pa);
 
 static void __init disable_pgtable_l5(void)
 {
@@ -855,18 +857,22 @@ static void __init set_mmap_rnd_bits_max(void)
  * underlying hardware: establish 1:1 mapping in 4-level page table mode
  * then read SATP to see if the configuration was taken into account
  * meaning sv48 is supported.
+ * The maximum SATP mode is limited by both the command line and the "mmu-type"
+ * property in the device tree, since some platforms may hang if an unsupported
+ * SATP mode is attempted.
  */
 static __init void set_satp_mode(uintptr_t dtb_pa)
 {
 	u64 identity_satp, hw_satp;
 	uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
-	u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
+	u64 satp_mode_limit = min_not_zero(__pi_set_satp_mode_from_cmdline(dtb_pa),
+					   __pi_set_satp_mode_from_fdt(dtb_pa));
 
 	kernel_map.page_offset = PAGE_OFFSET_L5;
 
-	if (satp_mode_cmdline == SATP_MODE_57) {
+	if (satp_mode_limit == SATP_MODE_48) {
 		disable_pgtable_l5();
-	} else if (satp_mode_cmdline == SATP_MODE_48) {
+	} else if (satp_mode_limit == SATP_MODE_39) {
 		disable_pgtable_l5();
 		disable_pgtable_l4();
 		return;