24 files changed, 605 insertions, 127 deletions

diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index d8bbd3207100..b355cf485671 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -51,5 +51,6 @@ ifeq ($(CONFIG_RISCV_SBI), y)
 obj-$(CONFIG_SMP) += cpu_ops_sbi.o
 endif
 obj-$(CONFIG_HOTPLUG_CPU)	+= cpu-hotplug.o
+obj-$(CONFIG_KGDB)		+= kgdb.o
 
 clean:
diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c
index 4c90c07d8c39..bd0f122965c3 100644
--- a/arch/riscv/kernel/cacheinfo.c
+++ b/arch/riscv/kernel/cacheinfo.c
@@ -7,6 +7,23 @@
 #include <linux/cpu.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <asm/cacheinfo.h>
+
+static struct riscv_cacheinfo_ops *rv_cache_ops;
+
+void riscv_set_cacheinfo_ops(struct riscv_cacheinfo_ops *ops)
+{
+	rv_cache_ops = ops;
+}
+EXPORT_SYMBOL_GPL(riscv_set_cacheinfo_ops);
+
+const struct attribute_group *
+cache_get_priv_group(struct cacheinfo *this_leaf)
+{
+	if (rv_cache_ops && rv_cache_ops->get_priv_group)
+		return rv_cache_ops->get_priv_group(this_leaf);
+	return NULL;
+}
 
 static void ci_leaf_init(struct cacheinfo *this_leaf,
 			 struct device_node *node,
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index 40a3c442ac5f..6d59e6906fdd 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -44,6 +44,22 @@ int riscv_of_processor_hartid(struct device_node *node)
 	return hart;
 }
 
+/*
+ * Find hart ID of the CPU DT node under which given DT node falls.
+ *
+ * To achieve this, we walk up the DT tree until we find an active
+ * RISC-V core (HART) node and extract the cpuid from it.
+ */
+int riscv_of_parent_hartid(struct device_node *node)
+{
+	for (; node; node = node->parent) {
+		if (of_device_is_compatible(node, "riscv"))
+			return riscv_of_processor_hartid(node);
+	}
+
+	return -1;
+}
+
 #ifdef CONFIG_PROC_FS
 
 static void print_isa(struct seq_file *f, const char *isa)
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 56d071b2c0a1..cae7e6d4c7ef 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -106,7 +106,9 @@ _save_context:
 
 	/* Handle interrupts */
 	move a0, sp /* pt_regs */
-	tail do_IRQ
+	la a1, handle_arch_irq
+	REG_L a1, (a1)
+	jr a1
 1:
 	/*
 	 * Exceptions run with interrupts enabled or disabled depending on the
diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
index ce69b34ff55d..08396614d6f4 100644
--- a/arch/riscv/kernel/ftrace.c
+++ b/arch/riscv/kernel/ftrace.c
@@ -7,10 +7,23 @@
 
 #include <linux/ftrace.h>
 #include <linux/uaccess.h>
+#include <linux/memory.h>
 #include <asm/cacheflush.h>
 #include <asm/patch.h>
 
 #ifdef CONFIG_DYNAMIC_FTRACE
+int ftrace_arch_code_modify_prepare(void) __acquires(&text_mutex)
+{
+	mutex_lock(&text_mutex);
+	return 0;
+}
+
+int ftrace_arch_code_modify_post_process(void) __releases(&text_mutex)
+{
+	mutex_unlock(&text_mutex);
+	return 0;
+}
+
 static int ftrace_check_current_call(unsigned long hook_pos,
 				     unsigned int *expected)
 {
@@ -51,7 +64,7 @@ static int __ftrace_modify_call(unsigned long hook_pos, unsigned long target,
 	make_call(hook_pos, target, call);
 
 	/* Replace the auipc-jalr pair at once. Return -EPERM on write error. */
-	if (riscv_patch_text_nosync
+	if (patch_text_nosync
 	    ((void *)hook_pos, enable ? call : nops, MCOUNT_INSN_SIZE))
 		return -EPERM;
 
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 98a406474e7d..7ed1b22950fd 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -161,11 +161,20 @@ ENTRY(_start_kernel)
 	/* Reset all registers except ra, a0, a1 */
 	call reset_regs
 
-	/* Setup a PMP to permit access to all of memory. */
+	/*
+	 * Setup a PMP to permit access to all of memory.  Some machines may
+	 * not implement PMPs, so we set up a quick trap handler to just skip
+	 * touching the PMPs on any trap.
+	 */
+	la a0, pmp_done
+	csrw CSR_TVEC, a0
+
 	li a0, -1
 	csrw CSR_PMPADDR0, a0
 	li a0, (PMP_A_NAPOT | PMP_R | PMP_W | PMP_X)
 	csrw CSR_PMPCFG0, a0
+.align 2
+pmp_done:
 
 	/*
 	 * The hartid in a0 is expected later on, and we have no firmware
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
index 345c4f2eba13..7207fa08d78f 100644
--- a/arch/riscv/kernel/irq.c
+++ b/arch/riscv/kernel/irq.c
@@ -7,7 +7,6 @@
 
 #include <linux/interrupt.h>
 #include <linux/irqchip.h>
-#include <linux/irqdomain.h>
 #include <linux/seq_file.h>
 #include <asm/smp.h>
 
@@ -17,37 +16,9 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 	return 0;
 }
 
-asmlinkage __visible void __irq_entry do_IRQ(struct pt_regs *regs)
-{
-	struct pt_regs *old_regs = set_irq_regs(regs);
-
-	irq_enter();
-	switch (regs->cause & ~CAUSE_IRQ_FLAG) {
-	case RV_IRQ_TIMER:
-		riscv_timer_interrupt();
-		break;
-#ifdef CONFIG_SMP
-	case RV_IRQ_SOFT:
-		/*
-		 * We only use software interrupts to pass IPIs, so if a non-SMP
-		 * system gets one, then we don't know what to do.
-		 */
-		riscv_software_interrupt();
-		break;
-#endif
-	case RV_IRQ_EXT:
-		handle_arch_irq(regs);
-		break;
-	default:
-		pr_alert("unexpected interrupt cause 0x%lx", regs->cause);
-		BUG();
-	}
-	irq_exit();
-
-	set_irq_regs(old_regs);
-}
-
 void __init init_IRQ(void)
 {
 	irqchip_init();
+	if (!handle_arch_irq)
+		panic("No interrupt controller found.");
 }
diff --git a/arch/riscv/kernel/kgdb.c b/arch/riscv/kernel/kgdb.c
new file mode 100644
index 000000000000..f16ade84a11f
--- /dev/null
+++ b/arch/riscv/kernel/kgdb.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 SiFive
+ */
+
+#include <linux/ptrace.h>
+#include <linux/kdebug.h>
+#include <linux/bug.h>
+#include <linux/kgdb.h>
+#include <linux/irqflags.h>
+#include <linux/string.h>
+#include <asm/cacheflush.h>
+#include <asm/gdb_xml.h>
+#include <asm/parse_asm.h>
+
+enum {
+	NOT_KGDB_BREAK = 0,
+	KGDB_SW_BREAK,
+	KGDB_COMPILED_BREAK,
+	KGDB_SW_SINGLE_STEP
+};
+
+static unsigned long stepped_address;
+static unsigned int stepped_opcode;
+
+#if __riscv_xlen == 32
+/* C.JAL is an RV32C-only instruction */
+DECLARE_INSN(c_jal, MATCH_C_JAL, MASK_C_JAL)
+#else
+#define is_c_jal_insn(opcode) 0
+#endif
+DECLARE_INSN(jalr, MATCH_JALR, MASK_JALR)
+DECLARE_INSN(jal, MATCH_JAL, MASK_JAL)
+DECLARE_INSN(c_jr, MATCH_C_JR, MASK_C_JR)
+DECLARE_INSN(c_jalr, MATCH_C_JALR, MASK_C_JALR)
+DECLARE_INSN(c_j, MATCH_C_J, MASK_C_J)
+DECLARE_INSN(beq, MATCH_BEQ, MASK_BEQ)
+DECLARE_INSN(bne, MATCH_BNE, MASK_BNE)
+DECLARE_INSN(blt, MATCH_BLT, MASK_BLT)
+DECLARE_INSN(bge, MATCH_BGE, MASK_BGE)
+DECLARE_INSN(bltu, MATCH_BLTU, MASK_BLTU)
+DECLARE_INSN(bgeu, MATCH_BGEU, MASK_BGEU)
+DECLARE_INSN(c_beqz, MATCH_C_BEQZ, MASK_C_BEQZ)
+DECLARE_INSN(c_bnez, MATCH_C_BNEZ, MASK_C_BNEZ)
+DECLARE_INSN(sret, MATCH_SRET, MASK_SRET)
+
+int decode_register_index(unsigned long opcode, int offset)
+{
+	return (opcode >> offset) & 0x1F;
+}
+
+int decode_register_index_short(unsigned long opcode, int offset)
+{
+	return ((opcode >> offset) & 0x7) + 8;
+}
+
+/* Calculate the new address for after a step */
+int get_step_address(struct pt_regs *regs, unsigned long *next_addr)
+{
+	unsigned long pc = regs->epc;
+	unsigned long *regs_ptr = (unsigned long *)regs;
+	unsigned int rs1_num, rs2_num;
+	int op_code;
+
+	if (probe_kernel_address((void *)pc, op_code))
+		return -EINVAL;
+	if ((op_code & __INSN_LENGTH_MASK) != __INSN_LENGTH_GE_32) {
+		if (is_c_jalr_insn(op_code) || is_c_jr_insn(op_code)) {
+			rs1_num = decode_register_index(op_code, RVC_C2_RS1_OPOFF);
+			*next_addr = regs_ptr[rs1_num];
+		} else if (is_c_j_insn(op_code) || is_c_jal_insn(op_code)) {
+			*next_addr = EXTRACT_RVC_J_IMM(op_code) + pc;
+		} else if (is_c_beqz_insn(op_code)) {
+			rs1_num = decode_register_index_short(op_code,
+							      RVC_C1_RS1_OPOFF);
+			if (!rs1_num || regs_ptr[rs1_num] == 0)
+				*next_addr = EXTRACT_RVC_B_IMM(op_code) + pc;
+			else
+				*next_addr = pc + 2;
+		} else if (is_c_bnez_insn(op_code)) {
+			rs1_num =
+			    decode_register_index_short(op_code, RVC_C1_RS1_OPOFF);
+			if (rs1_num && regs_ptr[rs1_num] != 0)
+				*next_addr = EXTRACT_RVC_B_IMM(op_code) + pc;
+			else
+				*next_addr = pc + 2;
+		} else {
+			*next_addr = pc + 2;
+		}
+	} else {
+		if ((op_code & __INSN_OPCODE_MASK) == __INSN_BRANCH_OPCODE) {
+			bool result = false;
+			long imm = EXTRACT_BTYPE_IMM(op_code);
+			unsigned long rs1_val = 0, rs2_val = 0;
+
+			rs1_num = decode_register_index(op_code, RVG_RS1_OPOFF);
+			rs2_num = decode_register_index(op_code, RVG_RS2_OPOFF);
+			if (rs1_num)
+				rs1_val = regs_ptr[rs1_num];
+			if (rs2_num)
+				rs2_val = regs_ptr[rs2_num];
+
+			if (is_beq_insn(op_code))
+				result = (rs1_val == rs2_val) ? true : false;
+			else if (is_bne_insn(op_code))
+				result = (rs1_val != rs2_val) ? true : false;
+			else if (is_blt_insn(op_code))
+				result =
+				    ((long)rs1_val <
+				     (long)rs2_val) ? true : false;
+			else if (is_bge_insn(op_code))
+				result =
+				    ((long)rs1_val >=
+				     (long)rs2_val) ? true : false;
+			else if (is_bltu_insn(op_code))
+				result = (rs1_val < rs2_val) ? true : false;
+			else if (is_bgeu_insn(op_code))
+				result = (rs1_val >= rs2_val) ? true : false;
+			if (result)
+				*next_addr = imm + pc;
+			else
+				*next_addr = pc + 4;
+		} else if (is_jal_insn(op_code)) {
+			*next_addr = EXTRACT_JTYPE_IMM(op_code) + pc;
+		} else if (is_jalr_insn(op_code)) {
+			rs1_num = decode_register_index(op_code, RVG_RS1_OPOFF);
+			if (rs1_num)
+				*next_addr = ((unsigned long *)regs)[rs1_num];
+			*next_addr += EXTRACT_ITYPE_IMM(op_code);
+		} else if (is_sret_insn(op_code)) {
+			*next_addr = pc;
+		} else {
+			*next_addr = pc + 4;
+		}
+	}
+	return 0;
+}
+
+int do_single_step(struct pt_regs *regs)
+{
+	/* Determine where the target instruction will send us to */
+	unsigned long addr = 0;
+	int error = get_step_address(regs, &addr);
+
+	if (error)
+		return error;
+
+	/* Store the op code in the stepped address */
+	error = probe_kernel_address((void *)addr, stepped_opcode);
+	if (error)
+		return error;
+
+	stepped_address = addr;
+
+	/* Replace the op code with the break instruction */
+	error = probe_kernel_write((void *)stepped_address,
+				   arch_kgdb_ops.gdb_bpt_instr,
+				   BREAK_INSTR_SIZE);
+	/* Flush and return */
+	if (!error) {
+		flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
+		kgdb_single_step = 1;
+		atomic_set(&kgdb_cpu_doing_single_step,
+			   raw_smp_processor_id());
+	} else {
+		stepped_address = 0;
+		stepped_opcode = 0;
+	}
+	return error;
+}
+
+/* Undo a single step */
+static void undo_single_step(struct pt_regs *regs)
+{
+	if (stepped_opcode != 0) {
+		probe_kernel_write((void *)stepped_address,
+				   (void *)&stepped_opcode, BREAK_INSTR_SIZE);
+		flush_icache_range(stepped_address,
+				   stepped_address + BREAK_INSTR_SIZE);
+	}
+	stepped_address = 0;
+	stepped_opcode = 0;
+	kgdb_single_step = 0;
+	atomic_set(&kgdb_cpu_doing_single_step, -1);
+}
+
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
+	{DBG_REG_ZERO, GDB_SIZEOF_REG, -1},
+	{DBG_REG_RA, GDB_SIZEOF_REG, offsetof(struct pt_regs, ra)},
+	{DBG_REG_SP, GDB_SIZEOF_REG, offsetof(struct pt_regs, sp)},
+	{DBG_REG_GP, GDB_SIZEOF_REG, offsetof(struct pt_regs, gp)},
+	{DBG_REG_TP, GDB_SIZEOF_REG, offsetof(struct pt_regs, tp)},
+	{DBG_REG_T0, GDB_SIZEOF_REG, offsetof(struct pt_regs, t0)},
+	{DBG_REG_T1, GDB_SIZEOF_REG, offsetof(struct pt_regs, t1)},
+	{DBG_REG_T2, GDB_SIZEOF_REG, offsetof(struct pt_regs, t2)},
+	{DBG_REG_FP, GDB_SIZEOF_REG, offsetof(struct pt_regs, s0)},
+	{DBG_REG_S1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)},
+	{DBG_REG_A0, GDB_SIZEOF_REG, offsetof(struct pt_regs, a0)},
+	{DBG_REG_A1, GDB_SIZEOF_REG, offsetof(struct pt_regs, a1)},
+	{DBG_REG_A2, GDB_SIZEOF_REG, offsetof(struct pt_regs, a2)},
+	{DBG_REG_A3, GDB_SIZEOF_REG, offsetof(struct pt_regs, a3)},
+	{DBG_REG_A4, GDB_SIZEOF_REG, offsetof(struct pt_regs, a4)},
+	{DBG_REG_A5, GDB_SIZEOF_REG, offsetof(struct pt_regs, a5)},
+	{DBG_REG_A6, GDB_SIZEOF_REG, offsetof(struct pt_regs, a6)},
+	{DBG_REG_A7, GDB_SIZEOF_REG, offsetof(struct pt_regs, a7)},
+	{DBG_REG_S2, GDB_SIZEOF_REG, offsetof(struct pt_regs, s2)},
+	{DBG_REG_S3, GDB_SIZEOF_REG, offsetof(struct pt_regs, s3)},
+	{DBG_REG_S4, GDB_SIZEOF_REG, offsetof(struct pt_regs, s4)},
+	{DBG_REG_S5, GDB_SIZEOF_REG, offsetof(struct pt_regs, s5)},
+	{DBG_REG_S6, GDB_SIZEOF_REG, offsetof(struct pt_regs, s6)},
+	{DBG_REG_S7, GDB_SIZEOF_REG, offsetof(struct pt_regs, s7)},
+	{DBG_REG_S8, GDB_SIZEOF_REG, offsetof(struct pt_regs, s8)},
+	{DBG_REG_S9, GDB_SIZEOF_REG, offsetof(struct pt_regs, s9)},
+	{DBG_REG_S10, GDB_SIZEOF_REG, offsetof(struct pt_regs, s10)},
+	{DBG_REG_S11, GDB_SIZEOF_REG, offsetof(struct pt_regs, s11)},
+	{DBG_REG_T3, GDB_SIZEOF_REG, offsetof(struct pt_regs, t3)},
+	{DBG_REG_T4, GDB_SIZEOF_REG, offsetof(struct pt_regs, t4)},
+	{DBG_REG_T5, GDB_SIZEOF_REG, offsetof(struct pt_regs, t5)},
+	{DBG_REG_T6, GDB_SIZEOF_REG, offsetof(struct pt_regs, t6)},
+	{DBG_REG_EPC, GDB_SIZEOF_REG, offsetof(struct pt_regs, epc)},
+	{DBG_REG_STATUS, GDB_SIZEOF_REG, offsetof(struct pt_regs, status)},
+	{DBG_REG_BADADDR, GDB_SIZEOF_REG, offsetof(struct pt_regs, badaddr)},
+	{DBG_REG_CAUSE, GDB_SIZEOF_REG, offsetof(struct pt_regs, cause)},
+};
+
+char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return NULL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
+		       dbg_reg_def[regno].size);
+	else
+		memset(mem, 0, dbg_reg_def[regno].size);
+	return dbg_reg_def[regno].name;
+}
+
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return -EINVAL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
+		       dbg_reg_def[regno].size);
+	return 0;
+}
+
+void
+sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
+{
+	/* Initialize to zero */
+	memset((char *)gdb_regs, 0, NUMREGBYTES);
+
+	gdb_regs[DBG_REG_SP_OFF] = task->thread.sp;
+	gdb_regs[DBG_REG_FP_OFF] = task->thread.s[0];
+	gdb_regs[DBG_REG_S1_OFF] = task->thread.s[1];
+	gdb_regs[DBG_REG_S2_OFF] = task->thread.s[2];
+	gdb_regs[DBG_REG_S3_OFF] = task->thread.s[3];
+	gdb_regs[DBG_REG_S4_OFF] = task->thread.s[4];
+	gdb_regs[DBG_REG_S5_OFF] = task->thread.s[5];
+	gdb_regs[DBG_REG_S6_OFF] = task->thread.s[6];
+	gdb_regs[DBG_REG_S7_OFF] = task->thread.s[7];
+	gdb_regs[DBG_REG_S8_OFF] = task->thread.s[8];
+	gdb_regs[DBG_REG_S9_OFF] = task->thread.s[10];
+	gdb_regs[DBG_REG_S10_OFF] = task->thread.s[11];
+	gdb_regs[DBG_REG_EPC_OFF] = task->thread.ra;
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+	regs->epc = pc;
+}
+
+void kgdb_arch_handle_qxfer_pkt(char *remcom_in_buffer,
+				char *remcom_out_buffer)
+{
+	if (!strncmp(remcom_in_buffer, gdb_xfer_read_target,
+		     sizeof(gdb_xfer_read_target)))
+		strcpy(remcom_out_buffer, riscv_gdb_stub_target_desc);
+	else if (!strncmp(remcom_in_buffer, gdb_xfer_read_cpuxml,
+			  sizeof(gdb_xfer_read_cpuxml)))
+		strcpy(remcom_out_buffer, riscv_gdb_stub_cpuxml);
+}
+
+static inline void kgdb_arch_update_addr(struct pt_regs *regs,
+					 char *remcom_in_buffer)
+{
+	unsigned long addr;
+	char *ptr;
+
+	ptr = &remcom_in_buffer[1];
+	if (kgdb_hex2long(&ptr, &addr))
+		regs->epc = addr;
+}
+
+int kgdb_arch_handle_exception(int vector, int signo, int err_code,
+			       char *remcom_in_buffer, char *remcom_out_buffer,
+			       struct pt_regs *regs)
+{
+	int err = 0;
+
+	undo_single_step(regs);
+
+	switch (remcom_in_buffer[0]) {
+	case 'c':
+	case 'D':
+	case 'k':
+		if (remcom_in_buffer[0] == 'c')
+			kgdb_arch_update_addr(regs, remcom_in_buffer);
+		break;
+	case 's':
+		kgdb_arch_update_addr(regs, remcom_in_buffer);
+		err = do_single_step(regs);
+		break;
+	default:
+		err = -1;
+	}
+	return err;
+}
+
+int kgdb_riscv_kgdbbreak(unsigned long addr)
+{
+	if (stepped_address == addr)
+		return KGDB_SW_SINGLE_STEP;
+	if (atomic_read(&kgdb_setting_breakpoint))
+		if (addr == (unsigned long)&kgdb_compiled_break)
+			return KGDB_COMPILED_BREAK;
+
+	return kgdb_has_hit_break(addr);
+}
+
+static int kgdb_riscv_notify(struct notifier_block *self, unsigned long cmd,
+			     void *ptr)
+{
+	struct die_args *args = (struct die_args *)ptr;
+	struct pt_regs *regs = args->regs;
+	unsigned long flags;
+	int type;
+
+	if (user_mode(regs))
+		return NOTIFY_DONE;
+
+	type = kgdb_riscv_kgdbbreak(regs->epc);
+	if (type == NOT_KGDB_BREAK && cmd == DIE_TRAP)
+		return NOTIFY_DONE;
+
+	local_irq_save(flags);
+
+	if (kgdb_handle_exception(type == KGDB_SW_SINGLE_STEP ? 0 : 1,
+				  args->signr, cmd, regs))
+		return NOTIFY_DONE;
+
+	if (type == KGDB_COMPILED_BREAK)
+		regs->epc += 4;
+
+	local_irq_restore(flags);
+
+	return NOTIFY_STOP;
+}
+
+static struct notifier_block kgdb_notifier = {
+	.notifier_call = kgdb_riscv_notify,
+};
+
+int kgdb_arch_init(void)
+{
+	register_die_notifier(&kgdb_notifier);
+
+	return 0;
+}
+
+void kgdb_arch_exit(void)
+{
+	unregister_die_notifier(&kgdb_notifier);
+}
+
+/*
+ * Global data
+ */
+#ifdef CONFIG_RISCV_ISA_C
+const struct kgdb_arch arch_kgdb_ops = {
+	.gdb_bpt_instr = {0x02, 0x90},	/* c.ebreak */
+};
+#else
+const struct kgdb_arch arch_kgdb_ops = {
+	.gdb_bpt_instr = {0x73, 0x00, 0x10, 0x00},	/* ebreak */
+};
+#endif
diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 8bbe5dbe1341..7191342c54da 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -10,7 +10,7 @@
 #include <linux/moduleloader.h>
 #include <linux/vmalloc.h>
 #include <linux/sizes.h>
-#include <asm/pgtable.h>
+#include <linux/pgtable.h>
 #include <asm/sections.h>
 
 static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v)
diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
index 8a4fc65ee022..d4a64dfed342 100644
--- a/arch/riscv/kernel/patch.c
+++ b/arch/riscv/kernel/patch.c
@@ -5,22 +5,22 @@
 
 #include <linux/spinlock.h>
 #include <linux/mm.h>
+#include <linux/memory.h>
 #include <linux/uaccess.h>
 #include <linux/stop_machine.h>
 #include <asm/kprobes.h>
 #include <asm/cacheflush.h>
 #include <asm/fixmap.h>
+#include <asm/patch.h>
 
-struct riscv_insn_patch {
+struct patch_insn {
 	void *addr;
 	u32 insn;
 	atomic_t cpu_count;
 };
 
 #ifdef CONFIG_MMU
-static DEFINE_RAW_SPINLOCK(patch_lock);
-
-static void __kprobes *patch_map(void *addr, int fixmap)
+static void *patch_map(void *addr, int fixmap)
 {
 	uintptr_t uintaddr = (uintptr_t) addr;
 	struct page *page;
@@ -37,20 +37,26 @@ static void __kprobes *patch_map(void *addr, int fixmap)
 	return (void *)set_fixmap_offset(fixmap, page_to_phys(page) +
 					 (uintaddr & ~PAGE_MASK));
 }
+NOKPROBE_SYMBOL(patch_map);
 
-static void __kprobes patch_unmap(int fixmap)
+static void patch_unmap(int fixmap)
 {
 	clear_fixmap(fixmap);
 }
+NOKPROBE_SYMBOL(patch_unmap);
 
-static int __kprobes riscv_insn_write(void *addr, const void *insn, size_t len)
+static int patch_insn_write(void *addr, const void *insn, size_t len)
 {
 	void *waddr = addr;
 	bool across_pages = (((uintptr_t) addr & ~PAGE_MASK) + len) > PAGE_SIZE;
-	unsigned long flags = 0;
 	int ret;
 
-	raw_spin_lock_irqsave(&patch_lock, flags);
+	/*
+	 * Before reaching here, it was expected to lock the text_mutex
+	 * already, so we don't need to give another lock here and could
+	 * ensure that it was safe between each cores.
+	 */
+	lockdep_assert_held(&text_mutex);
 
 	if (across_pages)
 		patch_map(addr + len, FIX_TEXT_POKE1);
@@ -64,38 +70,39 @@ static int __kprobes riscv_insn_write(void *addr, const void *insn, size_t len)
 	if (across_pages)
 		patch_unmap(FIX_TEXT_POKE1);
 
-	raw_spin_unlock_irqrestore(&patch_lock, flags);
-
 	return ret;
 }
+NOKPROBE_SYMBOL(patch_insn_write);
 #else
-static int __kprobes riscv_insn_write(void *addr, const void *insn, size_t len)
+static int patch_insn_write(void *addr, const void *insn, size_t len)
 {
 	return probe_kernel_write(addr, insn, len);
 }
+NOKPROBE_SYMBOL(patch_insn_write);
 #endif /* CONFIG_MMU */
 
-int __kprobes riscv_patch_text_nosync(void *addr, const void *insns, size_t len)
+int patch_text_nosync(void *addr, const void *insns, size_t len)
 {
 	u32 *tp = addr;
 	int ret;
 
-	ret = riscv_insn_write(tp, insns, len);
+	ret = patch_insn_write(tp, insns, len);
 
 	if (!ret)
 		flush_icache_range((uintptr_t) tp, (uintptr_t) tp + len);
 
 	return ret;
 }
+NOKPROBE_SYMBOL(patch_text_nosync);
 
-static int __kprobes riscv_patch_text_cb(void *data)
+static int patch_text_cb(void *data)
 {
-	struct riscv_insn_patch *patch = data;
+	struct patch_insn *patch = data;
 	int ret = 0;
 
 	if (atomic_inc_return(&patch->cpu_count) == 1) {
 		ret =
-		    riscv_patch_text_nosync(patch->addr, &patch->insn,
+		    patch_text_nosync(patch->addr, &patch->insn,
 					    GET_INSN_LENGTH(patch->insn));
 		atomic_inc(&patch->cpu_count);
 	} else {
@@ -106,15 +113,17 @@ static int __kprobes riscv_patch_text_cb(void *data)
 
 	return ret;
 }
+NOKPROBE_SYMBOL(patch_text_cb);
 
-int __kprobes riscv_patch_text(void *addr, u32 insn)
+int patch_text(void *addr, u32 insn)
 {
-	struct riscv_insn_patch patch = {
+	struct patch_insn patch = {
 		.addr = addr,
 		.insn = insn,
 		.cpu_count = ATOMIC_INIT(0),
 	};
 
-	return stop_machine_cpuslocked(riscv_patch_text_cb,
+	return stop_machine_cpuslocked(patch_text_cb,
 				       &patch, cpu_online_mask);
 }
+NOKPROBE_SYMBOL(patch_text);
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 145128a7e560..f04373be54a6 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -22,7 +22,6 @@
 #include <asm/cpu_ops.h>
 #include <asm/setup.h>
 #include <asm/sections.h>
-#include <asm/pgtable.h>
 #include <asm/sbi.h>
 #include <asm/tlbflush.h>
 #include <asm/thread_info.h>
@@ -75,7 +74,11 @@ void __init setup_arch(char **cmdline_p)
 
 	setup_bootmem();
 	paging_init();
+#if IS_ENABLED(CONFIG_BUILTIN_DTB)
+	unflatten_and_copy_device_tree();
+#else
 	unflatten_device_tree();
+#endif
 	clint_init_boot_cpu();
 
 #ifdef CONFIG_SWIOTLB
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index a65a8fa0c22d..b1d4f452f843 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -123,11 +123,14 @@ static inline void clear_ipi(void)
 		clint_clear_ipi(cpuid_to_hartid_map(smp_processor_id()));
 }
 
-void riscv_software_interrupt(void)
+void handle_IPI(struct pt_regs *regs)
 {
+	struct pt_regs *old_regs = set_irq_regs(regs);
 	unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
 	unsigned long *stats = ipi_data[smp_processor_id()].stats;
 
+	irq_enter();
+
 	clear_ipi();
 
 	while (true) {
@@ -138,7 +141,7 @@ void riscv_software_interrupt(void)
 
 		ops = xchg(pending_ipis, 0);
 		if (ops == 0)
-			return;
+			goto done;
 
 		if (ops & (1 << IPI_RESCHEDULE)) {
 			stats[IPI_RESCHEDULE]++;
@@ -160,6 +163,10 @@ void riscv_software_interrupt(void)
 		/* Order data access and bit testing. */
 		mb();
 	}
+
+done:
+	irq_exit();
+	set_irq_regs(old_regs);
 }
 
 static const char * const ipi_names[] = {
diff --git a/arch/riscv/kernel/soc.c b/arch/riscv/kernel/soc.c
index 0b3b3dc9ad0f..c7b0a73e382e 100644
--- a/arch/riscv/kernel/soc.c
+++ b/arch/riscv/kernel/soc.c
@@ -4,7 +4,7 @@
  */
 #include <linux/init.h>
 #include <linux/libfdt.h>
-#include <asm/pgtable.h>
+#include <linux/pgtable.h>
 #include <asm/soc.h>
 
 /*
@@ -26,3 +26,30 @@ void __init soc_early_init(void)
 		}
 	}
 }
+
+static bool soc_builtin_dtb_match(unsigned long vendor_id,
+				unsigned long arch_id, unsigned long imp_id,
+				const struct soc_builtin_dtb *entry)
+{
+	return entry->vendor_id == vendor_id &&
+	       entry->arch_id == arch_id &&
+	       entry->imp_id == imp_id;
+}
+
+void * __init soc_lookup_builtin_dtb(void)
+{
+	unsigned long vendor_id, arch_id, imp_id;
+	const struct soc_builtin_dtb *s;
+
+	__asm__ ("csrr %0, mvendorid" : "=r"(vendor_id));
+	__asm__ ("csrr %0, marchid" : "=r"(arch_id));
+	__asm__ ("csrr %0, mimpid" : "=r"(imp_id));
+
+	for (s = (void *)&__soc_builtin_dtb_table_start;
+	     (void *)s < (void *)&__soc_builtin_dtb_table_end; s++) {
+		if (soc_builtin_dtb_match(vendor_id, arch_id, imp_id, s))
+			return s->dtb_func();
+	}
+
+	return NULL;
+}
diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c
index 837b9b38f825..595342910c3f 100644
--- a/arch/riscv/kernel/stacktrace.c
+++ b/arch/riscv/kernel/stacktrace.c
@@ -99,17 +99,18 @@ void notrace walk_stackframe(struct task_struct *task,
 
 static bool print_trace_address(unsigned long pc, void *arg)
 {
-	print_ip_sym(pc);
+	const char *loglvl = arg;
+
+	print_ip_sym(loglvl, pc);
 	return false;
 }
 
-void show_stack(struct task_struct *task, unsigned long *sp)
+void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
 {
 	pr_cont("Call Trace:\n");
-	walk_stackframe(task, NULL, print_trace_address, NULL);
+	walk_stackframe(task, NULL, print_trace_address, (void *)loglvl);
 }
 
-
 static bool save_wchan(unsigned long pc, void *arg)
 {
 	if (!in_sched_functions(pc)) {
diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
index 6a53c02e9c73..4d3a1048ad8b 100644
--- a/arch/riscv/kernel/time.c
+++ b/arch/riscv/kernel/time.c
@@ -26,3 +26,12 @@ void __init time_init(void)
 	lpj_fine = riscv_timebase / HZ;
 	timer_probe();
 }
+
+void clocksource_arch_init(struct clocksource *cs)
+{
+#ifdef CONFIG_GENERIC_GETTIMEOFDAY
+	cs->vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER;
+#else
+	cs->vdso_clock_mode = VDSO_CLOCKMODE_NONE;
+#endif
+}
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 7f58fa53033f..ecec1778e3a4 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -147,6 +147,11 @@ asmlinkage __visible void do_trap_break(struct pt_regs *regs)
 {
 	if (user_mode(regs))
 		force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->epc);
+#ifdef CONFIG_KGDB
+	else if (notify_die(DIE_TRAP, "EBREAK", regs, 0, regs->cause, SIGTRAP)
+								== NOTIFY_STOP)
+		return;
+#endif
 	else if (report_bug(regs->epc, regs) == BUG_TRAP_TYPE_WARN)
 		regs->epc += get_break_insn_length(regs->epc);
 	else
@@ -178,6 +183,4 @@ void trap_init(void)
 	csr_write(CSR_SCRATCH, 0);
 	/* Set the exception vector address */
 	csr_write(CSR_TVEC, &handle_exception);
-	/* Enable interrupts */
-	csr_write(CSR_IE, IE_SIE);
 }
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index 484d95a70907..678204231700 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -11,8 +11,12 @@
 #include <linux/slab.h>
 #include <linux/binfmts.h>
 #include <linux/err.h>
-
+#include <asm/page.h>
+#ifdef GENERIC_TIME_VSYSCALL
+#include <vdso/datapage.h>
+#else
 #include <asm/vdso.h>
+#endif
 
 extern char vdso_start[], vdso_end[];
 
@@ -26,7 +30,7 @@ static union {
 	struct vdso_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
-static struct vdso_data *vdso_data = &vdso_data_store.data;
+struct vdso_data *vdso_data = &vdso_data_store.data;
 
 static int __init vdso_init(void)
 {
@@ -61,7 +65,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
 
 	vdso_len = (vdso_pages + 1) << PAGE_SHIFT;
 
-	down_write(&mm->mmap_sem);
+	mmap_write_lock(mm);
 	vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0);
 	if (IS_ERR_VALUE(vdso_base)) {
 		ret = vdso_base;
@@ -75,15 +79,24 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
 	 */
 	mm->context.vdso = (void *)vdso_base;
 
-	ret = install_special_mapping(mm, vdso_base, vdso_len,
+	ret =
+	   install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 		(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
 		vdso_pagelist);
 
-	if (unlikely(ret))
+	if (unlikely(ret)) {
 		mm->context.vdso = NULL;
+		goto end;
+	}
 
+	vdso_base += (vdso_pages << PAGE_SHIFT);
+	ret = install_special_mapping(mm, vdso_base, PAGE_SIZE,
+		(VM_READ | VM_MAYREAD), &vdso_pagelist[vdso_pages]);
+
+	if (unlikely(ret))
+		mm->context.vdso = NULL;
 end:
-	up_write(&mm->mmap_sem);
+	mmap_write_unlock(mm);
 	return ret;
 }
 
@@ -91,5 +104,8 @@ const char *arch_vma_name(struct vm_area_struct *vma)
 {
 	if (vma->vm_mm && (vma->vm_start == (long)vma->vm_mm->context.vdso))
 		return "[vdso]";
+	if (vma->vm_mm && (vma->vm_start ==
+			   (long)vma->vm_mm->context.vdso + PAGE_SIZE))
+		return "[vdso_data]";
 	return NULL;
 }
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index 4c8b2a4a6a70..38ba55b0eb9d 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -1,12 +1,14 @@
 # SPDX-License-Identifier: GPL-2.0-only
 # Copied from arch/tile/kernel/vdso/Makefile
 
+# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
+# the inclusion of generic Makefile.
+ARCH_REL_TYPE_ABS := R_RISCV_32|R_RISCV_64|R_RISCV_JUMP_SLOT
+include $(srctree)/lib/vdso/Makefile
 # Symbols present in the vdso
 vdso-syms  = rt_sigreturn
 ifdef CONFIG_64BIT
-vdso-syms += gettimeofday
-vdso-syms += clock_gettime
-vdso-syms += clock_getres
+vdso-syms += vgettimeofday
 endif
 vdso-syms += getcpu
 vdso-syms += flush_icache
@@ -14,6 +16,10 @@ vdso-syms += flush_icache
 # Files to link into the vdso
 obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
 
+ifneq ($(c-gettimeofday-y),)
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+endif
+
 # Build rules
 targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o
 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
diff --git a/arch/riscv/kernel/vdso/clock_getres.S b/arch/riscv/kernel/vdso/clock_getres.S
deleted file mode 100644
index 91378a52eb22..000000000000
--- a/arch/riscv/kernel/vdso/clock_getres.S
+++ /dev/null
@@ -1,18 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2017 SiFive
- */
-
-#include <linux/linkage.h>
-#include <asm/unistd.h>
-
-	.text
-/* int __vdso_clock_getres(clockid_t clock_id, struct timespec *res); */
-ENTRY(__vdso_clock_getres)
-	.cfi_startproc
-	/* For now, just do the syscall. */
-	li a7, __NR_clock_getres
-	ecall
-	ret
-	.cfi_endproc
-ENDPROC(__vdso_clock_getres)
diff --git a/arch/riscv/kernel/vdso/clock_gettime.S b/arch/riscv/kernel/vdso/clock_gettime.S
deleted file mode 100644
index 5371fd9bc01f..000000000000
--- a/arch/riscv/kernel/vdso/clock_gettime.S
+++ /dev/null
@@ -1,18 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2017 SiFive
- */
-
-#include <linux/linkage.h>
-#include <asm/unistd.h>
-
-	.text
-/* int __vdso_clock_gettime(clockid_t clock_id, struct timespec *tp); */
-ENTRY(__vdso_clock_gettime)
-	.cfi_startproc
-	/* For now, just do the syscall. */
-	li a7, __NR_clock_gettime
-	ecall
-	ret
-	.cfi_endproc
-ENDPROC(__vdso_clock_gettime)
diff --git a/arch/riscv/kernel/vdso/gettimeofday.S b/arch/riscv/kernel/vdso/gettimeofday.S
deleted file mode 100644
index e6fb8af88632..000000000000
--- a/arch/riscv/kernel/vdso/gettimeofday.S
+++ /dev/null
@@ -1,18 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2017 SiFive
- */
-
-#include <linux/linkage.h>
-#include <asm/unistd.h>
-
-	.text
-/* int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz); */
-ENTRY(__vdso_gettimeofday)
-	.cfi_startproc
-	/* For now, just do the syscall. */
-	li a7, __NR_gettimeofday
-	ecall
-	ret
-	.cfi_endproc
-ENDPROC(__vdso_gettimeofday)
diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S
index f66a091cb890..e6f558bca71b 100644
--- a/arch/riscv/kernel/vdso/vdso.lds.S
+++ b/arch/riscv/kernel/vdso/vdso.lds.S
@@ -2,11 +2,13 @@
 /*
  * Copyright (C) 2012 Regents of the University of California
  */
+#include <asm/page.h>
 
 OUTPUT_ARCH(riscv)
 
 SECTIONS
 {
+	PROVIDE(_vdso_data = . + PAGE_SIZE);
 	. = SIZEOF_HEADERS;
 
 	.hash		: { *(.hash) }			:text
diff --git a/arch/riscv/kernel/vdso/vgettimeofday.c b/arch/riscv/kernel/vdso/vgettimeofday.c
new file mode 100644
index 000000000000..d264943e2e47
--- /dev/null
+++ b/arch/riscv/kernel/vdso/vgettimeofday.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copied from arch/arm64/kernel/vdso/vgettimeofday.c
+ *
+ * Copyright (C) 2018 ARM Ltd.
+ * Copyright (C) 2020 SiFive
+ */
+
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __vdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+{
+	return __cvdso_clock_gettime(clock, ts);
+}
+
+int __vdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
+{
+	return __cvdso_gettimeofday(tv, tz);
+}
+
+int __vdso_clock_getres(clockid_t clock_id, struct __kernel_timespec *res)
+{
+	return __cvdso_clock_getres(clock_id, res);
+}
diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S
index 0339b6bbe11a..e6f8016b366a 100644
--- a/arch/riscv/kernel/vmlinux.lds.S
+++ b/arch/riscv/kernel/vmlinux.lds.S
@@ -34,6 +34,11 @@ SECTIONS
 		KEEP(*(__soc_early_init_table))
 		__soc_early_init_table_end = .;
 	}
+	__soc_builtin_dtb_table : {
+		__soc_builtin_dtb_table_start = .;
+		KEEP(*(__soc_builtin_dtb_table))
+		__soc_builtin_dtb_table_end = .;
+	}
 	/* we have to discard exit text and such at runtime, not link time */
 	.exit.text :
 	{