RVCK-Project · zhuzhenxxx-collab · Aug 11, 2026 · Aug 11, 2026 · Mar 27, 2024 · Mar 27, 2024
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
@@ -67,7 +67,7 @@ config RISCV
 	select ARCH_USE_MEMTEST
 	select ARCH_USE_QUEUED_RWLOCKS
 	select ARCH_USES_CFI_TRAPS if CFI_CLANG
-	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP && MMU
+	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if MMU
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
 	select ARCH_WANT_FRAME_POINTERS
 	select ARCH_WANT_GENERAL_HUGETLB if !RISCV_ISA_SVNAPOT

diff --git a/arch/riscv/boot/dts/thead/th1520.dtsi b/arch/riscv/boot/dts/thead/th1520.dtsi
@@ -452,10 +452,15 @@
 					      <&cpu3_intc 3>, <&cpu3_intc 7>;
 		};
 
-		aclint_sswi: aclint-sswi@ffdc00c000 {
-			compatible = "riscv,aclint-sswi";
+		aclint_sswi: interrupt-controller@ffdc00c000 {
+			compatible = "thead,c900-aclint-sswi";
 			reg = <0xff 0xdc00c000 0x0 0x00010000>;
+			#interrupt-cells = <0>;
 			interrupt-controller;
+			interrupts-extended = <&cpu0_intc 1>,
+					      <&cpu1_intc 1>,
+					      <&cpu2_intc 1>,
+					      <&cpu3_intc 1>;
 		};
 
 		secsys_reg: secsys-reg@ffff200000 {

diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c
@@ -43,6 +43,11 @@ static bool errata_cip_1200_check_func(unsigned long  arch_id, unsigned long imp
 		return false;
 	if ((impid & 0xffffff) > 0x200630 || impid == 0x1200626)
 		return false;
+
+#ifdef CONFIG_MMU
+	tlb_flush_all_threshold = 0;
+#endif
+
 	return true;
 }
 

diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
@@ -33,6 +33,9 @@ typedef struct {
 /* Lock the pointer masking mode because this mm is multithreaded */
 #define MM_CONTEXT_LOCK_PMLEN	0
 
+#define cntx2asid(cntx)		((cntx) & SATP_ASID_MASK)
+#define cntx2version(cntx)	((cntx) & ~SATP_ASID_MASK)
+
 void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
 				  pgprot_t prot);
 #endif /* __ASSEMBLY__ */

diff --git a/arch/riscv/include/asm/pgalloc.h b/arch/riscv/include/asm/pgalloc.h
@@ -8,13 +8,22 @@
 #define _ASM_RISCV_PGALLOC_H
 
 #include <linux/mm.h>
+#include <asm/sbi.h>
 #include <asm/tlb.h>
 
 #ifdef CONFIG_MMU
 #define __HAVE_ARCH_PUD_ALLOC_ONE
 #define __HAVE_ARCH_PUD_FREE
 #include <asm-generic/pgalloc.h>
 
+static inline void riscv_tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt)
+{
+	if (riscv_use_sbi_for_rfence())
+		tlb_remove_ptdesc(tlb, pt);
+	else
+		tlb_remove_page_ptdesc(tlb, pt);
+}
+
 static inline void pmd_populate_kernel(struct mm_struct *mm,
 	pmd_t *pmd, pte_t *pte)
 {
@@ -102,10 +111,7 @@ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
 		struct ptdesc *ptdesc = virt_to_ptdesc(pud);
 
 		pagetable_pud_dtor(ptdesc);
-		if (riscv_use_ipi_for_rfence())
-			tlb_remove_page_ptdesc(tlb, ptdesc);
-		else
-			tlb_remove_ptdesc(tlb, ptdesc);
+		riscv_tlb_remove_ptdesc(tlb, ptdesc);
 	}
 }
 
@@ -139,12 +145,8 @@ static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
 				  unsigned long addr)
 {
-	if (pgtable_l5_enabled) {
-		if (riscv_use_ipi_for_rfence())
-			tlb_remove_page_ptdesc(tlb, virt_to_ptdesc(p4d));
-		else
-			tlb_remove_ptdesc(tlb, virt_to_ptdesc(p4d));
-	}
+	if (pgtable_l5_enabled)
+		riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(p4d));
 }
 #endif /* __PAGETABLE_PMD_FOLDED */
 
@@ -176,10 +178,7 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
 	struct ptdesc *ptdesc = virt_to_ptdesc(pmd);
 
 	pagetable_pmd_dtor(ptdesc);
-	if (riscv_use_ipi_for_rfence())
-		tlb_remove_page_ptdesc(tlb, ptdesc);
-	else
-		tlb_remove_ptdesc(tlb, ptdesc);
+	riscv_tlb_remove_ptdesc(tlb, ptdesc);
 }
 
 #endif /* __PAGETABLE_PMD_FOLDED */
@@ -190,10 +189,7 @@ static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
 	struct ptdesc *ptdesc = page_ptdesc(pte);
 
 	pagetable_pte_dtor(ptdesc);
-	if (riscv_use_ipi_for_rfence())
-		tlb_remove_page_ptdesc(tlb, ptdesc);
-	else
-		tlb_remove_ptdesc(tlb, ptdesc);
+	riscv_tlb_remove_ptdesc(tlb, ptdesc);
 }
 #endif /* CONFIG_MMU */
 

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
@@ -728,8 +728,12 @@ unsigned long riscv_cached_marchid(unsigned int cpu_id);
 unsigned long riscv_cached_mimpid(unsigned int cpu_id);
 
 #if IS_ENABLED(CONFIG_SMP) && IS_ENABLED(CONFIG_RISCV_SBI)
+DECLARE_STATIC_KEY_FALSE(riscv_sbi_for_rfence);
+#define riscv_use_sbi_for_rfence() \
+	static_branch_unlikely(&riscv_sbi_for_rfence)
 void sbi_ipi_init(void);
 #else
+static inline bool riscv_use_sbi_for_rfence(void) { return false; }
 static inline void sbi_ipi_init(void) { }
 #endif
 

diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
@@ -49,12 +49,7 @@ void riscv_ipi_disable(void);
 bool riscv_ipi_have_virq_range(void);
 
 /* Set the IPI interrupt numbers for arch (called by irqchip drivers) */
-void riscv_ipi_set_virq_range(int virq, int nr, bool use_for_rfence);
-
-/* Check if we can use IPIs for remote FENCEs */
-DECLARE_STATIC_KEY_FALSE(riscv_ipi_for_rfence);
-#define riscv_use_ipi_for_rfence() \
-	static_branch_unlikely(&riscv_ipi_for_rfence)
+void riscv_ipi_set_virq_range(int virq, int nr);
 
 /* Check other CPUs stop or not */
 bool smp_crash_stop_failed(void);
@@ -104,16 +99,10 @@ static inline bool riscv_ipi_have_virq_range(void)
 	return false;
 }
 
-static inline void riscv_ipi_set_virq_range(int virq, int nr,
-					    bool use_for_rfence)
+static inline void riscv_ipi_set_virq_range(int virq, int nr)
 {
 }
 
-static inline bool riscv_use_ipi_for_rfence(void)
-{
-	return false;
-}
-
 #endif /* CONFIG_SMP */
 
 #if defined(CONFIG_HOTPLUG_CPU) && (CONFIG_SMP)

diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
@@ -15,8 +15,6 @@
 #define FLUSH_TLB_NO_ASID       ((unsigned long)-1)
 
 #ifdef CONFIG_MMU
-extern unsigned long asid_mask;
-
 static inline void local_flush_tlb_all(void)
 {
 	__asm__ __volatile__ ("sfence.vma" : : : "memory");
@@ -44,12 +42,7 @@ static inline void local_flush_tlb_page_asid(unsigned long addr,
 	else
 		local_flush_tlb_page(addr);
 }
-#else /* CONFIG_MMU */
-#define local_flush_tlb_all()			do { } while (0)
-#define local_flush_tlb_page(addr)		do { } while (0)
-#endif /* CONFIG_MMU */
 
-#if defined(CONFIG_SMP) && defined(CONFIG_MMU)
 void flush_tlb_all(void);
 void flush_tlb_mm(struct mm_struct *mm);
 void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
@@ -72,27 +65,9 @@ void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch,
 void arch_flush_tlb_batched_pending(struct mm_struct *mm);
 void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch);
 
-#else /* CONFIG_SMP && CONFIG_MMU */
-
-#define flush_tlb_all() local_flush_tlb_all()
-#define flush_tlb_page(vma, addr) local_flush_tlb_page(addr)
-
-static inline void flush_tlb_range(struct vm_area_struct *vma,
-		unsigned long start, unsigned long end)
-{
-	local_flush_tlb_all();
-}
-
-/* Flush a range of kernel pages */
-static inline void flush_tlb_kernel_range(unsigned long start,
-	unsigned long end)
-{
-	local_flush_tlb_all();
-}
-
-#define flush_tlb_mm(mm) flush_tlb_all()
-#define flush_tlb_mm_range(mm, start, end, page_size) flush_tlb_all()
-#define local_flush_tlb_kernel_range(start, end) flush_tlb_all()
-#endif /* !CONFIG_SMP || !CONFIG_MMU */
+extern unsigned long tlb_flush_all_threshold;
+#else /* CONFIG_MMU */
+#define local_flush_tlb_all()			do { } while (0)
+#endif /* CONFIG_MMU */
 
 #endif /* _ASM_RISCV_TLBFLUSH_H */
diff --git a/arch/riscv/kernel/sbi-ipi.c b/arch/riscv/kernel/sbi-ipi.c
@@ -3,34 +3,20 @@
  * Multiplex several IPIs over a single HW IPI.
  *
  * Copyright (c) 2022 Ventana Micro Systems Inc.
- * Copyright (C) 2024 Alibaba Group Holding Limited.
  */
 
 #define pr_fmt(fmt) "riscv: " fmt
 #include <linux/cpu.h>
 #include <linux/init.h>
 #include <linux/irq.h>
-#include <linux/irqchip.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqdomain.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
 #include <asm/sbi.h>
 
-static int sbi_ipi_virq;
-
-static u32 __iomem *sswi_base;
-
-static void sswi_send_ipi(unsigned int cpu)
-{
-	writel(1, sswi_base + cpuid_to_hartid_map(cpu));
-}
+DEFINE_STATIC_KEY_FALSE(riscv_sbi_for_rfence);
+EXPORT_SYMBOL_GPL(riscv_sbi_for_rfence);
 
-static void sswi_clear_ipi(void)
-{
-	writel(0, sswi_base + cpuid_to_hartid_map(smp_processor_id()));
-}
+static int sbi_ipi_virq;
 
 static void sbi_ipi_handle(struct irq_desc *desc)
 {
@@ -39,9 +25,6 @@ static void sbi_ipi_handle(struct irq_desc *desc)
 	chained_irq_enter(chip, desc);
 
 	csr_clear(CSR_IP, IE_SIE);
-	if (sswi_base)
-		sswi_clear_ipi();
-
 	ipi_mux_process();
 
 	chained_irq_exit(chip, desc);
@@ -74,8 +57,7 @@ void __init sbi_ipi_init(void)
 		return;
 	}
 
-	virq = ipi_mux_create(BITS_PER_BYTE, sswi_base ? sswi_send_ipi
-							: sbi_send_ipi);
+	virq = ipi_mux_create(BITS_PER_BYTE, sbi_send_ipi);
 	if (virq <= 0) {
 		pr_err("unable to create muxed IPIs\n");
 		irq_dispose_mapping(sbi_ipi_virq);
@@ -90,26 +72,15 @@ void __init sbi_ipi_init(void)
 	 * via generic IPI-Mux
 	 */
 	cpuhp_setup_state(CPUHP_AP_IRQ_RISCV_SBI_IPI_STARTING,
-			  sswi_base ?
-			  "irqchip/sswi-ipi:starting" :
 			  "irqchip/sbi-ipi:starting",
 			  sbi_ipi_starting_cpu, NULL);
 
-	riscv_ipi_set_virq_range(virq, BITS_PER_BYTE,
-				sswi_base ? true : false);
-	pr_info("providing IPIs using %s IPI extension\n",
-				sswi_base ? "ACLINT SSWI" : "SBI");
-}
-
-static int __init aclint_sswi_probe(struct device_node *node,
-				    struct device_node *parent)
-{
-	sswi_base = of_iomap(node, 0);
-	if (!sswi_base) {
-		pr_err("RISC-V ACLINT SSWI device probe failure\n");
-		return -ENODEV;
-	}
+	riscv_ipi_set_virq_range(virq, BITS_PER_BYTE);
+	pr_info("providing IPIs using SBI IPI extension\n");
 
-	return 0;
+	/*
+	 * Use the SBI remote fence extension to avoid
+	 * the extra context switch needed to handle IPIs.
+	 */
+	static_branch_enable(&riscv_sbi_for_rfence);
 }
-IRQCHIP_DECLARE(riscv_aclint_sswi, "riscv,aclint-sswi", aclint_sswi_probe);
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
@@ -176,10 +176,7 @@ bool riscv_ipi_have_virq_range(void)
 	return (ipi_virq_base) ? true : false;
 }
 
-DEFINE_STATIC_KEY_FALSE(riscv_ipi_for_rfence);
-EXPORT_SYMBOL_GPL(riscv_ipi_for_rfence);
-
-void riscv_ipi_set_virq_range(int virq, int nr, bool use_for_rfence)
+void riscv_ipi_set_virq_range(int virq, int nr)
 {
 	int i, err;
 
@@ -202,12 +199,6 @@ void riscv_ipi_set_virq_range(int virq, int nr, bool use_for_rfence)
 
 	/* Enabled IPIs for boot CPU immediately */
 	riscv_ipi_enable();
-
-	/* Update RFENCE static key */
-	if (use_for_rfence)
-		static_branch_enable(&riscv_ipi_for_rfence);
-	else
-		static_branch_disable(&riscv_ipi_for_rfence);
 }
 
 static const char * const ipi_names[] = {

diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
@@ -26,7 +26,7 @@
 #include <linux/sched/task_stack.h>
 #include <linux/sched/mm.h>
 
-#include <asm/cpufeature.h>
+#include <asm/cacheflush.h>
 #include <asm/cpu_ops.h>
 #include <asm/cpufeature.h>
 #include <asm/irq.h>
@@ -266,9 +266,10 @@ asmlinkage __visible void smp_callin(void)
 	}
 
 	/*
-	 * Remote TLB flushes are ignored while the CPU is offline, so emit
-	 * a local TLB flush right now just in case.
+	 * Remote cache and TLB flushes are ignored while the CPU is offline,
+	 * so flush them both right now just in case.
 	 */
+	local_flush_icache_all();
 	local_flush_tlb_all();
 #ifndef CONFIG_HOTPLUG_PARALLEL
 	complete(&cpu_running);

diff --git a/arch/riscv/mm/Makefile b/arch/riscv/mm/Makefile
@@ -13,14 +13,11 @@ endif
 KCOV_INSTRUMENT_init.o := n
 
 obj-y += init.o
-obj-$(CONFIG_MMU) += extable.o fault.o pageattr.o pgtable.o
+obj-$(CONFIG_MMU) += extable.o fault.o pageattr.o pgtable.o tlbflush.o
 obj-y += cacheflush.o
 obj-y += context.o
 obj-y += pmem.o
 
-ifeq ($(CONFIG_MMU),y)
-obj-$(CONFIG_SMP) += tlbflush.o
-endif
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
 obj-$(CONFIG_PTDUMP_CORE) += ptdump.o
 obj-$(CONFIG_KASAN)   += kasan_init.o

diff --git a/arch/riscv/mm/cacheflush.c b/arch/riscv/mm/cacheflush.c
@@ -21,7 +21,9 @@ void flush_icache_all(void)
 {
 	local_flush_icache_all();
 
-	if (IS_ENABLED(CONFIG_RISCV_SBI) && !riscv_use_ipi_for_rfence())
+	if (num_online_cpus() < 2)
+		return;
+	else if (riscv_use_sbi_for_rfence())
 		sbi_remote_fence_i(NULL);
 	else
 		on_each_cpu(ipi_remote_fence_i, NULL, 1);
@@ -69,8 +71,7 @@ void flush_icache_mm(struct mm_struct *mm, bool local)
 		 * with flush_icache_deferred().
 		 */
 		smp_mb();
-	} else if (IS_ENABLED(CONFIG_RISCV_SBI) &&
-		   !riscv_use_ipi_for_rfence()) {
+	} else if (riscv_use_sbi_for_rfence()) {
 		sbi_remote_fence_i(&others);
 	} else {
 		on_each_cpu_mask(&others, ipi_remote_fence_i, NULL, 1);