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authorXiang Wang <wxjstz@126.com>2018-08-09 16:20:35 +0800
committerPatrick Georgi <pgeorgi@google.com>2018-09-10 15:03:58 +0000
commitcda59b56ba1af83a64579901a5395c1b3c1bf519 (patch)
tree1ea1d63305663f76623b8db878e33f72b4867f82 /src/arch/riscv
parentaa5f821ee3313b869784eec25fab5da265225738 (diff)
downloadcoreboot-cda59b56ba1af83a64579901a5395c1b3c1bf519.tar.xz
riscv: update misaligned memory access exception handling
Support for more situations: floating point, compressed instructions, etc. Add support for redirect exception to S-Mode. Change-Id: I9983d56245eab1d458a84cb1432aeb805df7a49f Signed-off-by: Xiang Wang <wxjstz@126.com> Reviewed-on: https://review.coreboot.org/27972 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Diffstat (limited to 'src/arch/riscv')
-rw-r--r--src/arch/riscv/Makefile.inc4
-rw-r--r--src/arch/riscv/fp_asm.S362
-rw-r--r--src/arch/riscv/include/arch/exception.h11
-rw-r--r--src/arch/riscv/misaligned.c267
-rw-r--r--src/arch/riscv/trap_handler.c76
5 files changed, 652 insertions, 68 deletions
diff --git a/src/arch/riscv/Makefile.inc b/src/arch/riscv/Makefile.inc
index ae327f2f16..f4b69bb95e 100644
--- a/src/arch/riscv/Makefile.inc
+++ b/src/arch/riscv/Makefile.inc
@@ -43,6 +43,8 @@ ifeq ($(CONFIG_ARCH_BOOTBLOCK_RISCV),y)
bootblock-y = bootblock.S
bootblock-y += trap_util.S
bootblock-y += trap_handler.c
+bootblock-y += fp_asm.S
+bootblock-y += misaligned.c
bootblock-y += mcall.c
bootblock-y += virtual_memory.c
bootblock-y += boot.c
@@ -101,6 +103,8 @@ ramstage-y += ramstage.S
ramstage-y += mcall.c
ramstage-y += trap_util.S
ramstage-y += trap_handler.c
+ramstage-y += fp_asm.S
+ramstage-y += misaligned.c
ramstage-y += virtual_memory.c
ramstage-y += stages.c
ramstage-y += misc.c
diff --git a/src/arch/riscv/fp_asm.S b/src/arch/riscv/fp_asm.S
new file mode 100644
index 0000000000..9c6cc650d8
--- /dev/null
+++ b/src/arch/riscv/fp_asm.S
@@ -0,0 +1,362 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 HardenedLinux
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * This file define some function used to swap value between memory
+ * and float register. This will be used in misaligned access exception
+ * handling.
+ */
+
+#if defined(__riscv_flen)
+#if __riscv_flen >= 32
+
+ .text
+
+/* void read_f32(int regnum, uint32_t* v)
+ * regnum : which register want to read
+ * v : address to hold bits info of reading
+ */
+ .align 1
+ .globl read_f32
+read_f32:
+ la a2, .Lr32_t
+ andi a0, a0, 31
+ slli a0, a0, 1
+ add a0, a0, a2
+ lbu a0, 0(a0)
+ add a0, a0, a2
+ jr a0
+ .align 2
+.Lr32_t:
+ .half .Lr32_f0 - .Lr32_t
+ .half .Lr32_f1 - .Lr32_t
+ .half .Lr32_f2 - .Lr32_t
+ .half .Lr32_f3 - .Lr32_t
+ .half .Lr32_f4 - .Lr32_t
+ .half .Lr32_f5 - .Lr32_t
+ .half .Lr32_f6 - .Lr32_t
+ .half .Lr32_f7 - .Lr32_t
+ .half .Lr32_f8 - .Lr32_t
+ .half .Lr32_f9 - .Lr32_t
+ .half .Lr32_f10 - .Lr32_t
+ .half .Lr32_f11 - .Lr32_t
+ .half .Lr32_f12 - .Lr32_t
+ .half .Lr32_f13 - .Lr32_t
+ .half .Lr32_f14 - .Lr32_t
+ .half .Lr32_f15 - .Lr32_t
+ .half .Lr32_f16 - .Lr32_t
+ .half .Lr32_f17 - .Lr32_t
+ .half .Lr32_f18 - .Lr32_t
+ .half .Lr32_f19 - .Lr32_t
+ .half .Lr32_f20 - .Lr32_t
+ .half .Lr32_f21 - .Lr32_t
+ .half .Lr32_f22 - .Lr32_t
+ .half .Lr32_f23 - .Lr32_t
+ .half .Lr32_f24 - .Lr32_t
+ .half .Lr32_f25 - .Lr32_t
+ .half .Lr32_f26 - .Lr32_t
+ .half .Lr32_f27 - .Lr32_t
+ .half .Lr32_f28 - .Lr32_t
+ .half .Lr32_f29 - .Lr32_t
+ .half .Lr32_f30 - .Lr32_t
+ .half .Lr32_f31 - .Lr32_t
+#define read32(which) .Lr32_##which: fsw which, 0(a1); ret
+ read32(f0)
+ read32(f1)
+ read32(f2)
+ read32(f3)
+ read32(f4)
+ read32(f5)
+ read32(f6)
+ read32(f7)
+ read32(f8)
+ read32(f9)
+ read32(f10)
+ read32(f11)
+ read32(f12)
+ read32(f13)
+ read32(f14)
+ read32(f15)
+ read32(f16)
+ read32(f17)
+ read32(f18)
+ read32(f19)
+ read32(f20)
+ read32(f21)
+ read32(f22)
+ read32(f23)
+ read32(f24)
+ read32(f25)
+ read32(f26)
+ read32(f27)
+ read32(f28)
+ read32(f29)
+ read32(f30)
+ read32(f31)
+
+/* void write_f32(int regnum, uint32_t* v)
+ * regnum: which register want to write
+ * v : address to hold bits info of writing
+ */
+ .align 1
+ .globl write_f32
+write_f32:
+ la a2, .Lw32_t
+ andi a0, a0, 31
+ slli a0, a0, 1
+ add a0, a0, a2
+ lbu a0, 0(a0)
+ add a0, a0, a2
+ jr a0
+ .align 2
+.Lw32_t:
+ .half .Lw32_f0 - .Lw32_t
+ .half .Lw32_f1 - .Lw32_t
+ .half .Lw32_f2 - .Lw32_t
+ .half .Lw32_f3 - .Lw32_t
+ .half .Lw32_f4 - .Lw32_t
+ .half .Lw32_f5 - .Lw32_t
+ .half .Lw32_f6 - .Lw32_t
+ .half .Lw32_f7 - .Lw32_t
+ .half .Lw32_f8 - .Lw32_t
+ .half .Lw32_f9 - .Lw32_t
+ .half .Lw32_f10 - .Lw32_t
+ .half .Lw32_f11 - .Lw32_t
+ .half .Lw32_f12 - .Lw32_t
+ .half .Lw32_f13 - .Lw32_t
+ .half .Lw32_f14 - .Lw32_t
+ .half .Lw32_f15 - .Lw32_t
+ .half .Lw32_f16 - .Lw32_t
+ .half .Lw32_f17 - .Lw32_t
+ .half .Lw32_f18 - .Lw32_t
+ .half .Lw32_f19 - .Lw32_t
+ .half .Lw32_f20 - .Lw32_t
+ .half .Lw32_f21 - .Lw32_t
+ .half .Lw32_f22 - .Lw32_t
+ .half .Lw32_f23 - .Lw32_t
+ .half .Lw32_f24 - .Lw32_t
+ .half .Lw32_f25 - .Lw32_t
+ .half .Lw32_f26 - .Lw32_t
+ .half .Lw32_f27 - .Lw32_t
+ .half .Lw32_f28 - .Lw32_t
+ .half .Lw32_f29 - .Lw32_t
+ .half .Lw32_f30 - .Lw32_t
+ .half .Lw32_f31 - .Lw32_t
+#define write32(which) .Lw32_##which: flw which, 0(a1); ret
+ write32(f0)
+ write32(f1)
+ write32(f2)
+ write32(f3)
+ write32(f4)
+ write32(f5)
+ write32(f6)
+ write32(f7)
+ write32(f8)
+ write32(f9)
+ write32(f10)
+ write32(f11)
+ write32(f12)
+ write32(f13)
+ write32(f14)
+ write32(f15)
+ write32(f16)
+ write32(f17)
+ write32(f18)
+ write32(f19)
+ write32(f20)
+ write32(f21)
+ write32(f22)
+ write32(f23)
+ write32(f24)
+ write32(f25)
+ write32(f26)
+ write32(f27)
+ write32(f28)
+ write32(f29)
+ write32(f30)
+ write32(f31)
+#endif // __riscv_flen >= 32
+
+#if __riscv_flen >= 64
+
+ .text
+
+/* void read_f64(int regnum, uint64_t* v)
+ * regnum : which register want to read
+ * v : address to hold bits info of reading
+ */
+ .align 1
+ .globl read_f64
+read_f64:
+ la a2, .Lr64_t
+ andi a0, a0, 31
+ slli a0, a0, 1
+ add a0, a0, a2
+ lbu a0, 0(a0)
+ add a0, a0, a2
+ jr a0
+ .align 2
+.Lr64_t:
+ .half .Lr64_f0 - .Lr64_t
+ .half .Lr64_f1 - .Lr64_t
+ .half .Lr64_f2 - .Lr64_t
+ .half .Lr64_f3 - .Lr64_t
+ .half .Lr64_f4 - .Lr64_t
+ .half .Lr64_f5 - .Lr64_t
+ .half .Lr64_f6 - .Lr64_t
+ .half .Lr64_f7 - .Lr64_t
+ .half .Lr64_f8 - .Lr64_t
+ .half .Lr64_f9 - .Lr64_t
+ .half .Lr64_f10 - .Lr64_t
+ .half .Lr64_f11 - .Lr64_t
+ .half .Lr64_f12 - .Lr64_t
+ .half .Lr64_f13 - .Lr64_t
+ .half .Lr64_f14 - .Lr64_t
+ .half .Lr64_f15 - .Lr64_t
+ .half .Lr64_f16 - .Lr64_t
+ .half .Lr64_f17 - .Lr64_t
+ .half .Lr64_f18 - .Lr64_t
+ .half .Lr64_f19 - .Lr64_t
+ .half .Lr64_f20 - .Lr64_t
+ .half .Lr64_f21 - .Lr64_t
+ .half .Lr64_f22 - .Lr64_t
+ .half .Lr64_f23 - .Lr64_t
+ .half .Lr64_f24 - .Lr64_t
+ .half .Lr64_f25 - .Lr64_t
+ .half .Lr64_f26 - .Lr64_t
+ .half .Lr64_f27 - .Lr64_t
+ .half .Lr64_f28 - .Lr64_t
+ .half .Lr64_f29 - .Lr64_t
+ .half .Lr64_f30 - .Lr64_t
+ .half .Lr64_f31 - .Lr64_t
+#define read64(which) .Lr64_##which: fsd which, 0(a1); ret
+ read64(f0)
+ read64(f1)
+ read64(f2)
+ read64(f3)
+ read64(f4)
+ read64(f5)
+ read64(f6)
+ read64(f7)
+ read64(f8)
+ read64(f9)
+ read64(f10)
+ read64(f11)
+ read64(f12)
+ read64(f13)
+ read64(f14)
+ read64(f15)
+ read64(f16)
+ read64(f17)
+ read64(f18)
+ read64(f19)
+ read64(f20)
+ read64(f21)
+ read64(f22)
+ read64(f23)
+ read64(f24)
+ read64(f25)
+ read64(f26)
+ read64(f27)
+ read64(f28)
+ read64(f29)
+ read64(f30)
+ read64(f31)
+
+/* void write_f64(int regnum, uint64_t* v)
+ * regnum: which register want to write
+ * v : address to hold bits info of writing
+ */
+ .align 1
+ .globl write_f64
+write_f64:
+ la a2, .Lw64_t
+ andi a0, a0, 31
+ slli a0, a0, 1
+ add a0, a0, a2
+ lbu a0, 0(a0)
+ add a0, a0, a2
+ jr a0
+ .align 2
+.Lw64_t:
+ .half .Lw64_f0 - .Lw64_t
+ .half .Lw64_f1 - .Lw64_t
+ .half .Lw64_f2 - .Lw64_t
+ .half .Lw64_f3 - .Lw64_t
+ .half .Lw64_f4 - .Lw64_t
+ .half .Lw64_f5 - .Lw64_t
+ .half .Lw64_f6 - .Lw64_t
+ .half .Lw64_f7 - .Lw64_t
+ .half .Lw64_f8 - .Lw64_t
+ .half .Lw64_f9 - .Lw64_t
+ .half .Lw64_f10 - .Lw64_t
+ .half .Lw64_f11 - .Lw64_t
+ .half .Lw64_f12 - .Lw64_t
+ .half .Lw64_f13 - .Lw64_t
+ .half .Lw64_f14 - .Lw64_t
+ .half .Lw64_f15 - .Lw64_t
+ .half .Lw64_f16 - .Lw64_t
+ .half .Lw64_f17 - .Lw64_t
+ .half .Lw64_f18 - .Lw64_t
+ .half .Lw64_f19 - .Lw64_t
+ .half .Lw64_f20 - .Lw64_t
+ .half .Lw64_f21 - .Lw64_t
+ .half .Lw64_f22 - .Lw64_t
+ .half .Lw64_f23 - .Lw64_t
+ .half .Lw64_f24 - .Lw64_t
+ .half .Lw64_f25 - .Lw64_t
+ .half .Lw64_f26 - .Lw64_t
+ .half .Lw64_f27 - .Lw64_t
+ .half .Lw64_f28 - .Lw64_t
+ .half .Lw64_f29 - .Lw64_t
+ .half .Lw64_f30 - .Lw64_t
+ .half .Lw64_f31 - .Lw64_t
+#define write64(which) .Lw64_##which: fld which, 0(a1); ret
+ write64(f0)
+ write64(f1)
+ write64(f2)
+ write64(f3)
+ write64(f4)
+ write64(f5)
+ write64(f6)
+ write64(f7)
+ write64(f8)
+ write64(f9)
+ write64(f10)
+ write64(f11)
+ write64(f12)
+ write64(f13)
+ write64(f14)
+ write64(f15)
+ write64(f16)
+ write64(f17)
+ write64(f18)
+ write64(f19)
+ write64(f20)
+ write64(f21)
+ write64(f22)
+ write64(f23)
+ write64(f24)
+ write64(f25)
+ write64(f26)
+ write64(f27)
+ write64(f28)
+ write64(f29)
+ write64(f30)
+ write64(f31)
+
+#endif // __riscv_flen >= 64
+
+#endif // defined(__riscv_flen)
diff --git a/src/arch/riscv/include/arch/exception.h b/src/arch/riscv/include/arch/exception.h
index fc57b3b55c..6fbbdf0a89 100644
--- a/src/arch/riscv/include/arch/exception.h
+++ b/src/arch/riscv/include/arch/exception.h
@@ -32,8 +32,7 @@
#include <stdint.h>
-typedef struct
-{
+typedef struct {
uintptr_t gpr[32];
uintptr_t status;
uintptr_t epc;
@@ -53,9 +52,9 @@ static inline void exception_init(void)
{
}
-void trap_handler(trapframe* tf);
-void handle_supervisor_call(trapframe* tf);
-void handle_misaligned_load(trapframe *tf);
-void handle_misaligned_store(trapframe *tf);
+void redirect_trap(void);
+void trap_handler(trapframe *tf);
+void handle_supervisor_call(trapframe *tf);
+void handle_misaligned(trapframe *tf);
#endif
diff --git a/src/arch/riscv/misaligned.c b/src/arch/riscv/misaligned.c
new file mode 100644
index 0000000000..cb045b8323
--- /dev/null
+++ b/src/arch/riscv/misaligned.c
@@ -0,0 +1,267 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 HardenedLinux
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <vm.h>
+#include <arch/exception.h>
+#include <commonlib/helpers.h>
+
+/* these functions are defined in src/arch/riscv/fp_asm.S */
+#if defined(__riscv_flen)
+#if __riscv_flen >= 32
+extern void read_f32(int regnum, uint32_t *v);
+extern void write_f32(int regnum, uint32_t *v);
+#endif // __riscv_flen >= 32
+#if __riscv_flen >= 64
+extern void read_f64(int regnum, uint64_t *v);
+extern void write_f64(int regnum, uint64_t *v);
+#endif // __riscv_flen >= 64
+#endif // defined(__riscv_flen)
+
+/* This union makes it easy to read multibyte types by byte operations. */
+union endian_buf {
+ uint8_t b[8];
+ uint16_t h[4];
+ uint32_t w[2];
+ uint64_t d[1];
+ uintptr_t v;
+};
+
+/* This struct hold info of load/store instruction */
+struct memory_instruction_info {
+ /* opcode/mask used to identify instruction,
+ * (instruction_val) & mask == opcode */
+ uint32_t opcode;
+ uint32_t mask;
+ /* reg_shift/reg_mask/reg_addition used to get register number
+ * ((instruction_val >> reg_shift) & reg_mask) + reg_addition */
+ unsigned int reg_shift;
+ unsigned int reg_mask;
+ unsigned int reg_addition;
+ unsigned int is_fp : 1; /* mark as a float operation */
+ unsigned int is_load : 1; /* mark as a load operation */
+ unsigned int width : 8; /* Record the memory width of the operation */
+ unsigned int sign_extend : 1; /* mark need to be sign extended */
+};
+
+static struct memory_instruction_info insn_info[] = {
+#if __riscv_xlen == 128
+ { 0x00002000, 0x0000e003, 2, 7, 8, 0, 1, 16, 1}, // C.LQ
+#else
+ { 0x00002000, 0x0000e003, 2, 7, 8, 1, 1, 8, 0}, // C.FLD
+#endif
+ { 0x00004000, 0x0000e003, 2, 7, 8, 0, 1, 4, 1}, // C.LW
+#if __riscv_xlen == 32
+ { 0x00006000, 0x0000e003, 2, 7, 8, 1, 1, 4, 0}, // C.FLW
+#else
+ { 0x00006000, 0x0000e003, 2, 7, 8, 0, 1, 8, 1}, // C.LD
+#endif
+
+#if __riscv_xlen == 128
+ { 0x0000a000, 0x0000e003, 2, 7, 8, 0, 0, 16, 0}, // C.SQ
+#else
+ { 0x0000a000, 0x0000e003, 2, 7, 8, 1, 0, 8, 0}, // C.FSD
+#endif
+ { 0x0000c000, 0x0000e003, 2, 7, 8, 0, 0, 4, 0}, // C.SW
+#if __riscv_xlen == 32
+ { 0x0000e000, 0x0000e003, 2, 7, 8, 1, 0, 4, 0}, // C.FSW
+#else
+ { 0x0000e000, 0x0000e003, 2, 7, 8, 0, 0, 8, 0}, // C.SD
+#endif
+
+#if __riscv_xlen == 128
+ { 0x00002002, 0x0000e003, 7, 15, 0, 0, 1, 16, 1}, // C.LQSP
+#else
+ { 0x00002002, 0x0000e003, 7, 15, 0, 1, 1, 8, 0}, // C.FLDSP
+#endif
+ { 0x00004002, 0x0000e003, 7, 15, 0, 0, 1, 4, 1}, // C.LWSP
+#if __riscv_xlen == 32
+ { 0x00006002, 0x0000e003, 7, 15, 0, 1, 1, 4, 0}, // C.FLWSP
+#else
+ { 0x00006002, 0x0000e003, 7, 15, 0, 0, 1, 8, 1}, // C.LDSP
+#endif
+
+#if __riscv_xlen == 128
+ { 0x0000a002, 0x0000e003, 2, 15, 0, 0, 0, 16, 0}, // C.SQSP
+#else
+ { 0x0000a002, 0x0000e003, 2, 15, 0, 1, 0, 8, 0}, // C.FSDSP
+#endif
+ { 0x0000c002, 0x0000e003, 2, 15, 0, 0, 0, 4, 0}, // C.SWSP
+#if __riscv_xlen == 32
+ { 0x0000e002, 0x0000e003, 2, 15, 0, 1, 0, 4, 0}, // C.FSWSP
+#else
+ { 0x0000e002, 0x0000e003, 2, 15, 0, 0, 0, 8, 0}, // C.SDSP
+#endif
+
+ { 0x00000003, 0x0000707f, 7, 15, 0, 0, 1, 1, 1}, // LB
+ { 0x00001003, 0x0000707f, 7, 15, 0, 0, 1, 2, 1}, // LH
+ { 0x00002003, 0x0000707f, 7, 15, 0, 0, 1, 4, 1}, // LW
+#if __riscv_xlen > 32
+ { 0x00003003, 0x0000707f, 7, 15, 0, 0, 1, 8, 1}, // LD
+#endif
+ { 0x00004003, 0x0000707f, 7, 15, 0, 0, 1, 1, 0}, // LBU
+ { 0x00005003, 0x0000707f, 7, 15, 0, 0, 1, 2, 0}, // LHU
+ { 0x00006003, 0x0000707f, 7, 15, 0, 0, 1, 4, 0}, // LWU
+
+ { 0x00000023, 0x0000707f, 20, 15, 0, 0, 0, 1, 0}, // SB
+ { 0x00001023, 0x0000707f, 20, 15, 0, 0, 0, 2, 0}, // SH
+ { 0x00002023, 0x0000707f, 20, 15, 0, 0, 0, 4, 0}, // SW
+#if __riscv_xlen > 32
+ { 0x00003023, 0x0000707f, 20, 15, 0, 0, 0, 8, 0}, // SD
+#endif
+
+#if defined(__riscv_flen)
+#if __riscv_flen >= 32
+ { 0x00002007, 0x0000707f, 7, 15, 0, 1, 1, 4, 0}, // FLW
+ { 0x00003007, 0x0000707f, 7, 15, 0, 1, 1, 8, 0}, // FLD
+#endif // __riscv_flen >= 32
+
+#if __riscv_flen >= 64
+ { 0x00002027, 0x0000707f, 20, 15, 0, 1, 0, 4, 0}, // FSW
+ { 0x00003027, 0x0000707f, 20, 15, 0, 1, 0, 8, 0}, // FSD
+#endif // __riscv_flen >= 64
+#endif // defined(__riscv_flen)
+};
+
+static struct memory_instruction_info *match_instruction(uintptr_t insn)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(insn_info); i++)
+ if ((insn_info[i].mask & insn) == insn_info[i].opcode)
+ return &(insn_info[i]);
+ return NULL;
+}
+
+
+static int fetch_16bit_instruction(uintptr_t vaddr, uintptr_t *insn)
+{
+ uint16_t ins = mprv_read_mxr_u16((uint16_t *)vaddr);
+ if (EXTRACT_FIELD(ins, 0x3) != 3) {
+ *insn = ins;
+ return 0;
+ }
+ return -1;
+}
+
+static int fetch_32bit_instruction(uintptr_t vaddr, uintptr_t *insn)
+{
+ uint32_t l = (uint32_t)mprv_read_mxr_u16((uint16_t *)vaddr + 0);
+ uint32_t h = (uint32_t)mprv_read_mxr_u16((uint16_t *)vaddr + 2);
+ uint32_t ins = (h << 16) | l;
+ if ((EXTRACT_FIELD(ins, 0x3) == 3) &&
+ (EXTRACT_FIELD(ins, 0x1c) != 0x7)) {
+ *insn = ins;
+ return 0;
+ }
+ return -1;
+}
+
+
+void handle_misaligned(trapframe *tf)
+{
+ uintptr_t insn = 0;
+ union endian_buf buff;
+
+ /* try to fetch 16/32 bits instruction */
+ if (fetch_16bit_instruction(tf->epc, &insn))
+ if (fetch_32bit_instruction(tf->epc, &insn))
+ redirect_trap();
+
+ /* matching instruction */
+ struct memory_instruction_info *match = match_instruction(insn);
+
+ if (!match) {
+ redirect_trap();
+ return;
+ }
+
+ int regnum;
+ regnum = ((insn >> match->reg_shift) & match->reg_mask);
+ regnum = regnum + match->reg_addition;
+ buff.v = 0;
+ if (match->is_load) {
+ /* load operation */
+
+ /* reading from memory by bytes prevents misaligned
+ * memory access */
+ for (int i = 0; i < match->width; i++) {
+ uint8_t *addr = (uint8_t *)(tf->badvaddr + i);
+ buff.b[i] = mprv_read_u8(addr);
+ }
+
+ /* sign extend for signed integer loading */
+ if (match->sign_extend)
+ if (buff.v >> (8 * match->width - 1))
+ buff.v |= -1 << (8 * match->width);
+
+ /* write to register */
+ if (match->is_fp) {
+ int done = 0;
+#if defined(__riscv_flen)
+#if __riscv_flen >= 32
+ /* single-precision floating-point */
+ if (match->width == 4) {
+ write_f32(regnum, buff.w);
+ done = 1;
+ }
+#endif // __riscv_flen >= 32
+#if __riscv_flen >= 64
+ /* double-precision floating-point */
+ if (match->width == 8) {
+ write_f64(regnum, buff.d);
+ done = 1;
+ }
+#endif // __riscv_flen >= 64
+#endif // defined(__riscv_flen)
+ if (!done)
+ redirect_trap();
+ } else {
+ tf->gpr[regnum] = buff.v;
+ }
+ } else {
+ /* store operation */
+
+ /* reading from register */
+ if (match->is_fp) {
+ int done = 0;
+#if defined(__riscv_flen)
+#if __riscv_flen >= 32
+ if (match->width == 4) {
+ read_f32(regnum, buff.w);
+ done = 1;
+ }
+#endif // __riscv_flen >= 32
+#if __riscv_flen >= 64
+ if (match->width == 8) {
+ read_f64(regnum, buff.d);
+ done = 1;
+ }
+#endif // __riscv_flen >= 64
+#endif // defined(__riscv_flen)
+ if (!done)
+ redirect_trap();
+ } else {
+ buff.v = tf->gpr[regnum];
+ }
+
+ /* writing to memory by bytes prevents misaligned
+ * memory access */
+ for (int i = 0; i < match->width; i++) {
+ uint8_t *addr = (uint8_t *)(tf->badvaddr + i);
+ mprv_write_u8(addr, buff.b[i]);
+ }
+ }
+}
diff --git a/src/arch/riscv/trap_handler.c b/src/arch/riscv/trap_handler.c
index 7b35c2e7cd..772be64f40 100644
--- a/src/arch/riscv/trap_handler.c
+++ b/src/arch/riscv/trap_handler.c
@@ -166,12 +166,9 @@ void trap_handler(trapframe *tf)
print_trap_information(tf);
break;
case CAUSE_MISALIGNED_LOAD:
- print_trap_information(tf);
- handle_misaligned_load(tf);
- return;
case CAUSE_MISALIGNED_STORE:
print_trap_information(tf);
- handle_misaligned_store(tf);
+ handle_misaligned(tf);
return;
default:
printk(BIOS_EMERG, "================================\n");
@@ -184,62 +181,17 @@ void trap_handler(trapframe *tf)
die("Can't recover from trap. Halting.\n");
}
-static uint32_t fetch_instruction(uintptr_t vaddr) {
- printk(BIOS_SPEW, "fetching instruction at 0x%016zx\n", (size_t)vaddr);
- return mprv_read_u32((uint32_t *) vaddr);
-}
-
-void handle_misaligned_load(trapframe *tf) {
- printk(BIOS_DEBUG, "Trapframe ptr: %p\n", tf);
- uintptr_t faultingInstructionAddr = tf->epc;
- insn_t faultingInstruction = fetch_instruction(faultingInstructionAddr);
- printk(BIOS_DEBUG, "Faulting instruction: 0x%x\n", faultingInstruction);
- insn_t widthMask = 0x7000;
- insn_t memWidth = (faultingInstruction & widthMask) >> 12;
- insn_t destMask = 0xF80;
- insn_t destRegister = (faultingInstruction & destMask) >> 7;
- printk(BIOS_DEBUG, "Width: %d bits\n", (1 << memWidth) * 8);
- if (memWidth == 3) {
- // load double, handle the issue
- void* badAddress = (void*) tf->badvaddr;
- uint64_t value = 0;
- for (int i = 0; i < 8; i++) {
- value <<= 8;
- value += mprv_read_u8(badAddress+i);
- }
- tf->gpr[destRegister] = value;
- } else {
- // panic, this should not have happened
- die("Code should not reach this path, misaligned on a non-64 bit store/load\n");
- }
-
- // return to where we came from
- write_csr(mepc, read_csr(mepc) + 4);
-}
-
-void handle_misaligned_store(trapframe *tf) {
- printk(BIOS_DEBUG, "Trapframe ptr: %p\n", tf);
- uintptr_t faultingInstructionAddr = tf->epc;
- insn_t faultingInstruction = fetch_instruction(faultingInstructionAddr);
- printk(BIOS_DEBUG, "Faulting instruction: 0x%x\n", faultingInstruction);
- insn_t widthMask = 0x7000;
- insn_t memWidth = (faultingInstruction & widthMask) >> 12;
- insn_t srcMask = 0x1F00000;
- insn_t srcRegister = (faultingInstruction & srcMask) >> 20;
- printk(BIOS_DEBUG, "Width: %d bits\n", (1 << memWidth) * 8);
- if (memWidth == 3) {
- // store double, handle the issue
- void* badAddress = (void*) tf->badvaddr;
- uint64_t value = tf->gpr[srcRegister];
- for (int i = 0; i < 8; i++) {
- mprv_write_u8(badAddress+i, value);
- value >>= 8;
- }
- } else {
- // panic, this should not have happened
- die("Code should not reach this path, misaligned on a non-64 bit store/load\n");
- }
-
- // return to where we came from
- write_csr(mepc, read_csr(mepc) + 4);
+/* This function used to redirect trap to s-mode. */
+void redirect_trap(void)
+{
+ write_csr(sbadaddr, read_csr(mbadaddr));
+ write_csr(sepc, read_csr(mepc));
+ write_csr(scause, read_csr(mcause));
+ write_csr(mepc, read_csr(stvec));
+
+ uintptr_t status = read_csr(mstatus);
+ uintptr_t mpp = EXTRACT_FIELD(status, MSTATUS_MPP);
+ status = INSERT_FIELD(status, MSTATUS_MPP, 1);
+ status = INSERT_FIELD(status, MSTATUS_SPP, mpp & 1);
+ write_csr(mstatus, status);
}