16 files changed, 248 insertions, 76 deletions

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 865e14f50c14..b6722c246d9c 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -22,6 +22,7 @@ config RISCV
 	select GENERIC_ATOMIC64 if !64BIT || !RISCV_ISA_A
 	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select HAVE_MEMBLOCK
+	select HAVE_MEMBLOCK_NODE_MAP
 	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
 	select HAVE_GENERIC_DMA_COHERENT
@@ -43,6 +44,10 @@ config MMU
 config ARCH_PHYS_ADDR_T_64BIT
 	def_bool y
 
+config ZONE_DMA32
+	bool
+	default y
+
 config ARCH_DMA_ADDR_T_64BIT
 	def_bool y
 
@@ -55,6 +60,9 @@ config PAGE_OFFSET
 config STACKTRACE_SUPPORT
 	def_bool y
 
+config TRACE_IRQFLAGS_SUPPORT
+	def_bool y
+
 config RWSEM_GENERIC_SPINLOCK
 	def_bool y
 
@@ -107,6 +115,8 @@ config ARCH_RV64I
 	bool "RV64I"
 	select CPU_SUPPORTS_64BIT_KERNEL
 	select 64BIT
+	select HAVE_FUNCTION_TRACER
+	select HAVE_FUNCTION_GRAPH_TRACER
 
 endchoice
 
diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
index 681ac0d09314..4286a5f83876 100644
--- a/arch/riscv/include/asm/Kbuild
+++ b/arch/riscv/include/asm/Kbuild
@@ -12,7 +12,6 @@ generic-y += errno.h
 generic-y += exec.h
 generic-y += fb.h
 generic-y += fcntl.h
-generic-y += ftrace.h
 generic-y += futex.h
 generic-y += hardirq.h
 generic-y += hash.h
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 3c7a2c97e377..421fa3585798 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -40,15 +40,15 @@
 #define SR_SD   _AC(0x8000000000000000, UL) /* FS/XS dirty */
 #endif
 
-/* SPTBR flags */
+/* SATP flags */
 #if __riscv_xlen == 32
-#define SPTBR_PPN     _AC(0x003FFFFF, UL)
-#define SPTBR_MODE_32 _AC(0x80000000, UL)
-#define SPTBR_MODE    SPTBR_MODE_32
+#define SATP_PPN     _AC(0x003FFFFF, UL)
+#define SATP_MODE_32 _AC(0x80000000, UL)
+#define SATP_MODE    SATP_MODE_32
 #else
-#define SPTBR_PPN     _AC(0x00000FFFFFFFFFFF, UL)
-#define SPTBR_MODE_39 _AC(0x8000000000000000, UL)
-#define SPTBR_MODE    SPTBR_MODE_39
+#define SATP_PPN     _AC(0x00000FFFFFFFFFFF, UL)
+#define SATP_MODE_39 _AC(0x8000000000000000, UL)
+#define SATP_MODE    SATP_MODE_39
 #endif
 
 /* Interrupt Enable and Interrupt Pending flags */
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
new file mode 100644
index 000000000000..66d4175eb13e
--- /dev/null
+++ b/arch/riscv/include/asm/ftrace.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2017 Andes Technology Corporation */
+
+/*
+ * The graph frame test is not possible if CONFIG_FRAME_POINTER is not enabled.
+ * Check arch/riscv/kernel/mcount.S for detail.
+ */
+#if defined(CONFIG_FUNCTION_GRAPH_TRACER) && defined(CONFIG_FRAME_POINTER)
+#define HAVE_FUNCTION_GRAPH_FP_TEST
+#endif
diff --git a/arch/riscv/include/asm/mmu_context.h b/arch/riscv/include/asm/mmu_context.h
index 97424834dce2..336d60ec5698 100644
--- a/arch/riscv/include/asm/mmu_context.h
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -39,16 +39,6 @@ static inline void destroy_context(struct mm_struct *mm)
 {
 }
 
-static inline pgd_t *current_pgdir(void)
-{
-	return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
-}
-
-static inline void set_pgdir(pgd_t *pgd)
-{
-	csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
-}
-
 /*
  * When necessary, performs a deferred icache flush for the given MM context,
  * on the local CPU.  RISC-V has no direct mechanism for instruction cache
@@ -93,7 +83,12 @@ static inline void switch_mm(struct mm_struct *prev,
 		cpumask_clear_cpu(cpu, mm_cpumask(prev));
 		cpumask_set_cpu(cpu, mm_cpumask(next));
 
-		set_pgdir(next->pgd);
+		/*
+		 * Use the old spbtr name instead of using the current satp
+		 * name to support binutils 2.29 which doesn't know about the
+		 * privileged ISA 1.10 yet.
+		 */
+		csr_write(sptbr, virt_to_pfn(next->pgd) | SATP_MODE);
 		local_flush_tlb_all();
 
 		flush_icache_deferred(next);
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
index 7b9c24ebdf52..7b209aec355d 100644
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -36,7 +36,14 @@ static inline void local_flush_tlb_page(unsigned long addr)
 
 #define flush_tlb_all() local_flush_tlb_all()
 #define flush_tlb_page(vma, addr) local_flush_tlb_page(addr)
-#define flush_tlb_range(vma, start, end) local_flush_tlb_all()
+
+static inline void flush_tlb_range(struct vm_area_struct *vma,
+		unsigned long start, unsigned long end)
+{
+	local_flush_tlb_all();
+}
+
+#define flush_tlb_mm(mm) flush_tlb_all()
 
 #else /* CONFIG_SMP */
 
@@ -45,16 +52,13 @@ static inline void local_flush_tlb_page(unsigned long addr)
 #define flush_tlb_all() sbi_remote_sfence_vma(0, 0, -1)
 #define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
 #define flush_tlb_range(vma, start, end) \
-	sbi_remote_sfence_vma(0, start, (end) - (start))
+	sbi_remote_sfence_vma(mm_cpumask((vma)->vm_mm)->bits, \
+			      start, (end) - (start))
+#define flush_tlb_mm(mm) \
+	sbi_remote_sfence_vma(mm_cpumask(mm)->bits, 0, -1)
 
 #endif /* CONFIG_SMP */
 
-/* Flush the TLB entries of the specified mm context */
-static inline void flush_tlb_mm(struct mm_struct *mm)
-{
-	flush_tlb_all();
-}
-
 /* Flush a range of kernel pages */
 static inline void flush_tlb_kernel_range(unsigned long start,
 	unsigned long end)
diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h
index 2f704a5c4196..080fb28061de 100644
--- a/arch/riscv/include/asm/unistd.h
+++ b/arch/riscv/include/asm/unistd.h
@@ -11,7 +11,6 @@
  *   GNU General Public License for more details.
  */
 
-#define __ARCH_HAVE_MMU
 #define __ARCH_WANT_SYS_CLONE
 #include <uapi/asm/unistd.h>
 #include <uapi/asm/syscalls.h>
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index ab8baf7bd142..196f62ffc428 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -2,6 +2,11 @@
 # Makefile for the RISC-V Linux kernel
 #
 
+ifdef CONFIG_FTRACE
+CFLAGS_REMOVE_ftrace.o = -pg
+CFLAGS_REMOVE_setup.o = -pg
+endif
+
 extra-y += head.o
 extra-y += vmlinux.lds
 
@@ -29,5 +34,7 @@ CFLAGS_setup.o := -mcmodel=medany
 obj-$(CONFIG_SMP)		+= smpboot.o
 obj-$(CONFIG_SMP)		+= smp.o
 obj-$(CONFIG_MODULES)		+= module.o
+obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o
+obj-$(CONFIG_FUNCTION_GRAPH_TRACER)	+= ftrace.o
 
 clean:
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 7404ec222406..87fc045be51f 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -78,10 +78,13 @@ _save_context:
 	REG_S x31, PT_T6(sp)
 
 	/*
-	 * Disable FPU to detect illegal usage of
-	 * floating point in kernel space
+	 * Disable user-mode memory access as it should only be set in the
+	 * actual user copy routines.
+	 *
+	 * Disable the FPU to detect illegal usage of floating point in kernel
+	 * space.
 	 */
-	li t0, SR_FS
+	li t0, SR_SUM | SR_FS
 
 	REG_L s0, TASK_TI_USER_SP(tp)
 	csrrc s1, sstatus, t0
diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
new file mode 100644
index 000000000000..d0de68d144cb
--- /dev/null
+++ b/arch/riscv/kernel/ftrace.c
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ * Copyright (C) 2017 Andes Technology Corporation
+ */
+
+#include <linux/ftrace.h>
+
+/*
+ * Most of this file is copied from arm64.
+ */
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
+			   unsigned long frame_pointer)
+{
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
+	unsigned long old;
+	struct ftrace_graph_ent trace;
+	int err;
+
+	if (unlikely(atomic_read(&current->tracing_graph_pause)))
+		return;
+
+	/*
+	 * We don't suffer access faults, so no extra fault-recovery assembly
+	 * is needed here.
+	 */
+	old = *parent;
+
+	trace.func = self_addr;
+	trace.depth = current->curr_ret_stack + 1;
+
+	if (!ftrace_graph_entry(&trace))
+		return;
+
+	err = ftrace_push_return_trace(old, self_addr, &trace.depth,
+				       frame_pointer, NULL);
+	if (err == -EBUSY)
+		return;
+	*parent = return_hooker;
+}
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 78f670d70133..226eeb190f90 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -74,15 +74,15 @@ relocate:
 	sub a1, a1, a0
 	add ra, ra, a1
 
-	/* Point stvec to virtual address of intruction after sptbr write */
+	/* Point stvec to virtual address of intruction after satp write */
 	la a0, 1f
 	add a0, a0, a1
 	csrw stvec, a0
 
-	/* Compute sptbr for kernel page tables, but don't load it yet */
+	/* Compute satp for kernel page tables, but don't load it yet */
 	la a2, swapper_pg_dir
 	srl a2, a2, PAGE_SHIFT
-	li a1, SPTBR_MODE
+	li a1, SATP_MODE
 	or a2, a2, a1
 
 	/*
diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S
new file mode 100644
index 000000000000..c46a778627be
--- /dev/null
+++ b/arch/riscv/kernel/mcount.S
@@ -0,0 +1,126 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2017 Andes Technology Corporation */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/asm.h>
+#include <asm/csr.h>
+#include <asm/unistd.h>
+#include <asm/thread_info.h>
+#include <asm/asm-offsets.h>
+#include <asm-generic/export.h>
+#include <asm/ftrace.h>
+
+	.text
+
+	.macro SAVE_ABI_STATE
+	addi	sp, sp, -16
+	sd	s0, 0(sp)
+	sd	ra, 8(sp)
+	addi	s0, sp, 16
+	.endm
+
+	/*
+	 * The call to ftrace_return_to_handler would overwrite the return
+	 * register if a0 was not saved.
+	 */
+	.macro SAVE_RET_ABI_STATE
+	addi	sp, sp, -32
+	sd	s0, 16(sp)
+	sd	ra, 24(sp)
+	sd	a0, 8(sp)
+	addi	s0, sp, 32
+	.endm
+
+	.macro STORE_ABI_STATE
+	ld	ra, 8(sp)
+	ld	s0, 0(sp)
+	addi	sp, sp, 16
+	.endm
+
+	.macro STORE_RET_ABI_STATE
+	ld	ra, 24(sp)
+	ld	s0, 16(sp)
+	ld	a0, 8(sp)
+	addi	sp, sp, 32
+	.endm
+
+ENTRY(ftrace_stub)
+	ret
+ENDPROC(ftrace_stub)
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ENTRY(return_to_handler)
+/*
+ * On implementing the frame point test, the ideal way is to compare the
+ * s0 (frame pointer, if enabled) on entry and the sp (stack pointer) on return.
+ * However, the psABI of variable-length-argument functions does not allow this.
+ *
+ * So alternatively we check the *old* frame pointer position, that is, the
+ * value stored in -16(s0) on entry, and the s0 on return.
+ */
+#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
+	mv	t6, s0
+#endif
+	SAVE_RET_ABI_STATE
+#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
+	mv	a0, t6
+#endif
+	la	t0, ftrace_return_to_handler
+	jalr	t0
+	mv	a1, a0
+	STORE_RET_ABI_STATE
+	jalr	a1
+ENDPROC(return_to_handler)
+EXPORT_SYMBOL(return_to_handler)
+#endif
+
+ENTRY(_mcount)
+	la	t4, ftrace_stub
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+	la	t0, ftrace_graph_return
+	ld	t1, 0(t0)
+	bne	t1, t4, do_ftrace_graph_caller
+
+	la	t3, ftrace_graph_entry
+	ld	t2, 0(t3)
+	la	t6, ftrace_graph_entry_stub
+	bne	t2, t6, do_ftrace_graph_caller
+#endif
+	la	t3, ftrace_trace_function
+	ld	t5, 0(t3)
+	bne	t5, t4, do_trace
+	ret
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * A pseudo representation for the function graph tracer:
+ * prepare_to_return(&ra_to_caller_of_caller, ra_to_caller)
+ */
+do_ftrace_graph_caller:
+	addi	a0, s0, -8
+	mv	a1, ra
+#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
+	ld	a2, -16(s0)
+#endif
+	SAVE_ABI_STATE
+	la	t0, prepare_ftrace_return
+	jalr	t0
+	STORE_ABI_STATE
+	ret
+#endif
+
+/*
+ * A pseudo representation for the function tracer:
+ * (*ftrace_trace_function)(ra_to_caller, ra_to_caller_of_caller)
+ */
+do_trace:
+	ld	a1, -8(s0)
+	mv	a0, ra
+
+	SAVE_ABI_STATE
+	jalr	t5
+	STORE_ABI_STATE
+	ret
+ENDPROC(_mcount)
+EXPORT_SYMBOL(_mcount)
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index cb7b0c63014e..09f7064e898c 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -49,10 +49,6 @@ struct screen_info screen_info = {
 };
 #endif
 
-#ifdef CONFIG_CMDLINE_BOOL
-static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
-#endif /* CONFIG_CMDLINE_BOOL */
-
 unsigned long va_pa_offset;
 EXPORT_SYMBOL(va_pa_offset);
 unsigned long pfn_base;
@@ -153,25 +149,6 @@ void __init sbi_save(unsigned int hartid, void *dtb)
 	early_init_dt_scan(__va(dtb));
 }
 
-/*
- * Allow the user to manually add a memory region (in case DTS is broken);
- * "mem_end=nn[KkMmGg]"
- */
-static int __init mem_end_override(char *p)
-{
-	resource_size_t base, end;
-
-	if (!p)
-		return -EINVAL;
-	base = (uintptr_t) __pa(PAGE_OFFSET);
-	end = memparse(p, &p) & PMD_MASK;
-	if (end == 0)
-		return -EINVAL;
-	memblock_add(base, end - base);
-	return 0;
-}
-early_param("mem_end", mem_end_override);
-
 static void __init setup_bootmem(void)
 {
 	struct memblock_region *reg;
@@ -204,22 +181,19 @@ static void __init setup_bootmem(void)
 	early_init_fdt_scan_reserved_mem();
 	memblock_allow_resize();
 	memblock_dump_all();
+
+	for_each_memblock(memory, reg) {
+		unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
+		unsigned long end_pfn = memblock_region_memory_end_pfn(reg);
+
+		memblock_set_node(PFN_PHYS(start_pfn),
+		                  PFN_PHYS(end_pfn - start_pfn),
+		                  &memblock.memory, 0);
+	}
 }
 
 void __init setup_arch(char **cmdline_p)
 {
-#ifdef CONFIG_CMDLINE_BOOL
-#ifdef CONFIG_CMDLINE_OVERRIDE
-	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-#else
-	if (builtin_cmdline[0] != '\0') {
-		/* Append bootloader command line to built-in */
-		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
-		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
-		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
-	}
-#endif /* CONFIG_CMDLINE_OVERRIDE */
-#endif /* CONFIG_CMDLINE_BOOL */
 	*cmdline_p = boot_command_line;
 
 	parse_early_param();
diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index e8a178df8144..582cb153eb24 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -74,7 +74,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
 
 	down_write(&mm->mmap_sem);
 	vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0);
-	if (unlikely(IS_ERR_VALUE(vdso_base))) {
+	if (IS_ERR_VALUE(vdso_base)) {
 		ret = vdso_base;
 		goto end;
 	}
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index ceebfc29305b..148c98ca9b45 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -238,6 +238,10 @@ vmalloc_fault:
 		 * Do _not_ use "tsk->active_mm->pgd" here.
 		 * We might be inside an interrupt in the middle
 		 * of a task switch.
+		 *
+		 * Note: Use the old spbtr name instead of using the current
+		 * satp name to support binutils 2.29 which doesn't know about
+		 * the privileged ISA 1.10 yet.
 		 */
 		index = pgd_index(addr);
 		pgd = (pgd_t *)pfn_to_virt(csr_read(sptbr)) + index;
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 9f4bee5e51fd..c77df8142be2 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -17,6 +17,7 @@
 #include <linux/initrd.h>
 #include <linux/memblock.h>
 #include <linux/swap.h>
+#include <linux/sizes.h>
 
 #include <asm/tlbflush.h>
 #include <asm/sections.h>
@@ -25,11 +26,12 @@
 
 static void __init zone_sizes_init(void)
 {
-	unsigned long zones_size[MAX_NR_ZONES];
+	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
 
-	memset(zones_size, 0, sizeof(zones_size));
-	zones_size[ZONE_NORMAL] = max_mapnr;
-	free_area_init_node(0, zones_size, pfn_base, NULL);
+	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn));
+	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
+
+	free_area_init_nodes(max_zone_pfns);
 }
 
 void setup_zero_page(void)
@@ -39,8 +41,6 @@ void setup_zero_page(void)
 
 void __init paging_init(void)
 {
-	init_mm.pgd = (pgd_t *)pfn_to_virt(csr_read(sptbr));
-
 	setup_zero_page();
 	local_flush_tlb_all();
 	zone_sizes_init();