Merge tag 'riscv-for-linus-6.1-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull more RISC-V updates from Palmer Dabbelt:

 - DT updates for the PolarFire SOC

 - a fix to correct the handling of write-only mappings

 - m{vetndor,arcd,imp}id is now in /proc/cpuinfo

 - the SiFive L2 cache controller support has been refactored to also
   support L3 caches

 - misc fixes, cleanups and improvements throughout the tree

* tag 'riscv-for-linus-6.1-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits)
  MAINTAINERS: add RISC-V's patchwork
  RISC-V: Make port I/O string accessors actually work
  riscv: enable software resend of irqs
  RISC-V: Re-enable counter access from userspace
  riscv: vdso: fix NULL deference in vdso_join_timens() when vfork
  riscv: Add cache information in AUX vector
  soc: sifive: ccache: define the macro for the register shifts
  soc: sifive: ccache: use pr_fmt() to remove CCACHE: prefixes
  soc: sifive: ccache: reduce printing on init
  soc: sifive: ccache: determine the cache level from dts
  soc: sifive: ccache: Rename SiFive L2 cache to Composable cache.
  dt-bindings: sifive-ccache: change Sifive L2 cache to Composable cache
  riscv: check for kernel config option in t-head memory types errata
  riscv: use BIT() marco for cpufeature probing
  riscv: use BIT() macros in t-head errata init
  riscv: drop some idefs from CMO initialization
  riscv: cleanup svpbmt cpufeature probing
  riscv: Pass -mno-relax only on lld < 15.0.0
  RISC-V: Avoid dereferening NULL regs in die()
  dt-bindings: riscv: add new riscv,isa strings for emulators
  ...

arch/riscv/kernel/cpu.c

@@ -3,10 +3,13 @@
  * Copyright (C) 2012 Regents of the University of California
  */
 
+#include <linux/cpu.h>
 #include <linux/init.h>
 #include <linux/seq_file.h>
 #include <linux/of.h>
+#include <asm/csr.h>
 #include <asm/hwcap.h>
+#include <asm/sbi.h>
 #include <asm/smp.h>
 #include <asm/pgtable.h>
 
@@ -68,6 +71,50 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
 }
 
 #ifdef CONFIG_PROC_FS
+
+struct riscv_cpuinfo {
+	unsigned long mvendorid;
+	unsigned long marchid;
+	unsigned long mimpid;
+};
+static DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
+
+static int riscv_cpuinfo_starting(unsigned int cpu)
+{
+	struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
+
+#if IS_ENABLED(CONFIG_RISCV_SBI)
+	ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
+	ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
+	ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
+#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
+	ci->mvendorid = csr_read(CSR_MVENDORID);
+	ci->marchid = csr_read(CSR_MARCHID);
+	ci->mimpid = csr_read(CSR_MIMPID);
+#else
+	ci->mvendorid = 0;
+	ci->marchid = 0;
+	ci->mimpid = 0;
+#endif
+
+	return 0;
+}
+
+static int __init riscv_cpuinfo_init(void)
+{
+	int ret;
+
+	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting",
+				riscv_cpuinfo_starting, NULL);
+	if (ret < 0) {
+		pr_err("cpuinfo: failed to register hotplug callbacks.\n");
+		return ret;
+	}
+
+	return 0;
+}
+device_initcall(riscv_cpuinfo_init);
+
 #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \
 	{							\
 		.uprop = #UPROP,				\
@@ -186,6 +233,7 @@ 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);
+	struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id);
 	const char *compat, *isa;
 
 	seq_printf(m, "processor\t: %lu\n", cpu_id);
@@ -196,6 +244,9 @@ static int c_show(struct seq_file *m, void *v)
 	if (!of_property_read_string(node, "compatible", &compat)
 	    && strcmp(compat, "riscv"))
 		seq_printf(m, "uarch\t\t: %s\n", compat);
+	seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid);
+	seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid);
+	seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid);
 	seq_puts(m, "\n");
 	of_node_put(node);