Merge https://gitlab.denx.de/u-boot/custodians/u-boot-riscvWIP/16Aug2019

- Fix sifive serial y-modem transfer.
- Access CSRs using CSR numbers.
- Update doc sifive-fu540
- Support big endian hosts and target.

9 files changed, 426 insertions, 484 deletions

diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
index e9a8b437ed..5ca185745e 100644
--- a/arch/riscv/cpu/cpu.c
+++ b/arch/riscv/cpu/cpu.c
@@ -7,7 +7,6 @@
 #include <cpu.h>
 #include <dm.h>
 #include <log.h>
-#include <asm/csr.h>
 #include <asm/encoding.h>
 #include <dm/uclass-internal.h>
 
@@ -48,7 +47,7 @@ static inline bool supports_extension(char ext)
 	return false;
 #else  /* !CONFIG_CPU */
 #ifdef CONFIG_RISCV_MMODE
-	return csr_read(misa) & (1 << (ext - 'a'));
+	return csr_read(CSR_MISA) & (1 << (ext - 'a'));
 #else  /* !CONFIG_RISCV_MMODE */
 #warning "There is no way to determine the available extensions in S-mode."
 #warning "Please convert your board to use the RISC-V CPU driver."
@@ -82,7 +81,7 @@ int arch_cpu_init_dm(void)
 	/* Enable FPU */
 	if (supports_extension('d') || supports_extension('f')) {
 		csr_set(MODE_PREFIX(status), MSTATUS_FS);
-		csr_write(fcsr, 0);
+		csr_write(CSR_FCSR, 0);
 	}
 
 	if (CONFIG_IS_ENABLED(RISCV_MMODE)) {
@@ -90,11 +89,11 @@ int arch_cpu_init_dm(void)
 		 * Enable perf counters for cycle, time,
 		 * and instret counters only
 		 */
-		csr_write(mcounteren, GENMASK(2, 0));
+		csr_write(CSR_MCOUNTEREN, GENMASK(2, 0));
 
 		/* Disable paging */
 		if (supports_extension('s'))
-			csr_write(satp, 0);
+			csr_write(CSR_SATP, 0);
 	}
 
 	return 0;
diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S
index 60ac8c621e..e06db404f5 100644
--- a/arch/riscv/cpu/start.S
+++ b/arch/riscv/cpu/start.S
@@ -13,7 +13,6 @@
 #include <config.h>
 #include <common.h>
 #include <elf.h>
-#include <asm/csr.h>
 #include <asm/encoding.h>
 #include <generated/asm-offsets.h>
 
@@ -41,7 +40,7 @@ secondary_harts_relocation_error:
 .globl _start
 _start:
 #ifdef CONFIG_RISCV_MMODE
-	csrr	a0, mhartid
+	csrr	a0, CSR_MHARTID
 #endif
 
 	/* save hart id and dtb pointer */
diff --git a/arch/riscv/include/asm/asm.h b/arch/riscv/include/asm/asm.h
new file mode 100644
index 0000000000..5a02b7d509
--- /dev/null
+++ b/arch/riscv/include/asm/asm.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2015 Regents of the University of California
+ */
+
+#ifndef _ASM_RISCV_ASM_H
+#define _ASM_RISCV_ASM_H
+
+#ifdef __ASSEMBLY__
+#define __ASM_STR(x)	x
+#else
+#define __ASM_STR(x)	#x
+#endif
+
+#if __riscv_xlen == 64
+#define __REG_SEL(a, b)	__ASM_STR(a)
+#elif __riscv_xlen == 32
+#define __REG_SEL(a, b)	__ASM_STR(b)
+#else
+#error "Unexpected __riscv_xlen"
+#endif
+
+#define REG_L		__REG_SEL(ld, lw)
+#define REG_S		__REG_SEL(sd, sw)
+#define SZREG		__REG_SEL(8, 4)
+#define LGREG		__REG_SEL(3, 2)
+
+#if __SIZEOF_POINTER__ == 8
+#ifdef __ASSEMBLY__
+#define RISCV_PTR		.dword
+#define RISCV_SZPTR		8
+#define RISCV_LGPTR		3
+#else
+#define RISCV_PTR		".dword"
+#define RISCV_SZPTR		"8"
+#define RISCV_LGPTR		"3"
+#endif
+#elif __SIZEOF_POINTER__ == 4
+#ifdef __ASSEMBLY__
+#define RISCV_PTR		.word
+#define RISCV_SZPTR		4
+#define RISCV_LGPTR		2
+#else
+#define RISCV_PTR		".word"
+#define RISCV_SZPTR		"4"
+#define RISCV_LGPTR		"2"
+#endif
+#else
+#error "Unexpected __SIZEOF_POINTER__"
+#endif
+
+#if (__SIZEOF_INT__ == 4)
+#define RISCV_INT		__ASM_STR(.word)
+#define RISCV_SZINT		__ASM_STR(4)
+#define RISCV_LGINT		__ASM_STR(2)
+#else
+#error "Unexpected __SIZEOF_INT__"
+#endif
+
+#if (__SIZEOF_SHORT__ == 2)
+#define RISCV_SHORT		__ASM_STR(.half)
+#define RISCV_SZSHORT		__ASM_STR(2)
+#define RISCV_LGSHORT		__ASM_STR(1)
+#else
+#error "Unexpected __SIZEOF_SHORT__"
+#endif
+
+#endif /* _ASM_RISCV_ASM_H */
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 644e6baa15..d1520743a2 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Copyright (C) 2015 Regents of the University of California
  *
@@ -8,13 +8,14 @@
 #ifndef _ASM_RISCV_CSR_H
 #define _ASM_RISCV_CSR_H
 
+#include <asm/asm.h>
 #include <linux/const.h>
 
 /* Status register flags */
 #define SR_SIE		_AC(0x00000002, UL) /* Supervisor Interrupt Enable */
 #define SR_SPIE		_AC(0x00000020, UL) /* Previous Supervisor IE */
 #define SR_SPP		_AC(0x00000100, UL) /* Previously Supervisor */
-#define SR_SUM		_AC(0x00040000, UL) /* Supervisor access User Memory */
+#define SR_SUM		_AC(0x00040000, UL) /* Supervisor User Memory Access */
 
 #define SR_FS		_AC(0x00006000, UL) /* Floating-point Status */
 #define SR_FS_OFF	_AC(0x00000000, UL)
@@ -35,7 +36,7 @@
 #endif
 
 /* SATP flags */
-#if __riscv_xlen == 32
+#ifndef CONFIG_64BIT
 #define SATP_PPN	_AC(0x003FFFFF, UL)
 #define SATP_MODE_32	_AC(0x80000000, UL)
 #define SATP_MODE	SATP_MODE_32
@@ -45,10 +46,18 @@
 #define SATP_MODE	SATP_MODE_39
 #endif
 
-/* Interrupt Enable and Interrupt Pending flags */
-#define MIE_MSIE	_AC(0x00000008, UL) /* Software Interrupt Enable */
-#define SIE_SSIE	_AC(0x00000002, UL) /* Software Interrupt Enable */
-#define SIE_STIE	_AC(0x00000020, UL) /* Timer Interrupt Enable */
+/* SCAUSE */
+#define SCAUSE_IRQ_FLAG		(_AC(1, UL) << (__riscv_xlen - 1))
+
+#define IRQ_U_SOFT		0
+#define IRQ_S_SOFT		1
+#define IRQ_M_SOFT		3
+#define IRQ_U_TIMER		4
+#define IRQ_S_TIMER		5
+#define IRQ_M_TIMER		7
+#define IRQ_U_EXT		8
+#define IRQ_S_EXT		9
+#define IRQ_M_EXT		11
 
 #define EXC_INST_MISALIGNED	0
 #define EXC_INST_ACCESS		1
@@ -60,14 +69,47 @@
 #define EXC_LOAD_PAGE_FAULT	13
 #define EXC_STORE_PAGE_FAULT	15
 
-#ifndef __ASSEMBLY__
+/* SIE (Interrupt Enable) and SIP (Interrupt Pending) flags */
+#define MIE_MSIE		(_AC(0x1, UL) << IRQ_M_SOFT)
+#define SIE_SSIE		(_AC(0x1, UL) << IRQ_S_SOFT)
+#define SIE_STIE		(_AC(0x1, UL) << IRQ_S_TIMER)
+#define SIE_SEIE		(_AC(0x1, UL) << IRQ_S_EXT)
+
+#define CSR_FCSR		0x003
+#define CSR_CYCLE		0xc00
+#define CSR_TIME		0xc01
+#define CSR_INSTRET		0xc02
+#define CSR_SSTATUS		0x100
+#define CSR_SIE			0x104
+#define CSR_STVEC		0x105
+#define CSR_SCOUNTEREN		0x106
+#define CSR_SSCRATCH		0x140
+#define CSR_SEPC		0x141
+#define CSR_SCAUSE		0x142
+#define CSR_STVAL		0x143
+#define CSR_SIP			0x144
+#define CSR_SATP		0x180
+#define CSR_MSTATUS		0x300
+#define CSR_MISA		0x301
+#define CSR_MIE			0x304
+#define CSR_MTVEC		0x305
+#define CSR_MCOUNTEREN		0x306
+#define CSR_MSCRATCH		0x340
+#define CSR_MEPC		0x341
+#define CSR_MCAUSE		0x342
+#define CSR_MTVAL		0x343
+#define CSR_MIP			0x344
+#define CSR_CYCLEH		0xc80
+#define CSR_TIMEH		0xc81
+#define CSR_INSTRETH		0xc82
+#define CSR_MHARTID		0xf14
 
-#define xcsr(csr)	#csr
+#ifndef __ASSEMBLY__
 
 #define csr_swap(csr, val)					\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrrw %0, " xcsr(csr) ", %1"	\
+	__asm__ __volatile__ ("csrrw %0, " __ASM_STR(csr) ", %1"\
 			      : "=r" (__v) : "rK" (__v)		\
 			      : "memory");			\
 	__v;							\
@@ -76,7 +118,7 @@
 #define csr_read(csr)						\
 ({								\
 	register unsigned long __v;				\
-	__asm__ __volatile__ ("csrr %0, " xcsr(csr)		\
+	__asm__ __volatile__ ("csrr %0, " __ASM_STR(csr)	\
 			      : "=r" (__v) :			\
 			      : "memory");			\
 	__v;							\
@@ -85,7 +127,7 @@
 #define csr_write(csr, val)					\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrw " xcsr(csr) ", %0"		\
+	__asm__ __volatile__ ("csrw " __ASM_STR(csr) ", %0"	\
 			      : : "rK" (__v)			\
 			      : "memory");			\
 })
@@ -93,7 +135,7 @@
 #define csr_read_set(csr, val)					\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrrs %0, " xcsr(csr) ", %1"	\
+	__asm__ __volatile__ ("csrrs %0, " __ASM_STR(csr) ", %1"\
 			      : "=r" (__v) : "rK" (__v)		\
 			      : "memory");			\
 	__v;							\
@@ -102,7 +144,7 @@
 #define csr_set(csr, val)					\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrs " xcsr(csr) ", %0"		\
+	__asm__ __volatile__ ("csrs " __ASM_STR(csr) ", %0"	\
 			      : : "rK" (__v)			\
 			      : "memory");			\
 })
@@ -110,7 +152,7 @@
 #define csr_read_clear(csr, val)				\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrrc %0, " xcsr(csr) ", %1"	\
+	__asm__ __volatile__ ("csrrc %0, " __ASM_STR(csr) ", %1"\
 			      : "=r" (__v) : "rK" (__v)		\
 			      : "memory");			\
 	__v;							\
@@ -119,7 +161,7 @@
 #define csr_clear(csr, val)					\
 ({								\
 	unsigned long __v = (unsigned long)(val);		\
-	__asm__ __volatile__ ("csrc " xcsr(csr) ", %0"		\
+	__asm__ __volatile__ ("csrc " __ASM_STR(csr) ", %0"	\
 			      : : "rK" (__v)			\
 			      : "memory");			\
 })
diff --git a/arch/riscv/include/asm/encoding.h b/arch/riscv/include/asm/encoding.h
index 772668c74e..c450eb9103 100644
--- a/arch/riscv/include/asm/encoding.h
+++ b/arch/riscv/include/asm/encoding.h
@@ -7,6 +7,8 @@
 #ifndef RISCV_CSR_ENCODING_H
 #define RISCV_CSR_ENCODING_H
 
+#include <asm/csr.h>
+
 #ifdef CONFIG_RISCV_SMODE
 #define MODE_PREFIX(__suffix)	s##__suffix
 #else
@@ -49,13 +51,10 @@
 #define SSTATUS64_SD	0x8000000000000000
 
 #define MIP_SSIP	BIT(IRQ_S_SOFT)
-#define MIP_HSIP	BIT(IRQ_H_SOFT)
 #define MIP_MSIP	BIT(IRQ_M_SOFT)
 #define MIP_STIP	BIT(IRQ_S_TIMER)
-#define MIP_HTIP	BIT(IRQ_H_TIMER)
 #define MIP_MTIP	BIT(IRQ_M_TIMER)
 #define MIP_SEIP	BIT(IRQ_S_EXT)
-#define MIP_HEIP	BIT(IRQ_H_EXT)
 #define MIP_MEIP	BIT(IRQ_M_EXT)
 
 #define SIP_SSIP	MIP_SSIP
@@ -73,18 +72,6 @@
 #define VM_SV39		9
 #define VM_SV48		10
 
-#define IRQ_S_SOFT	1
-#define IRQ_H_SOFT	2
-#define IRQ_M_SOFT	3
-#define IRQ_S_TIMER	5
-#define IRQ_H_TIMER	6
-#define IRQ_M_TIMER	7
-#define IRQ_S_EXT	9
-#define IRQ_H_EXT	10
-#define IRQ_M_EXT	11
-#define IRQ_COP		12
-#define IRQ_HOST	13
-
 #define CAUSE_MISALIGNED_FETCH		0
 #define CAUSE_FETCH_ACCESS		1
 #define CAUSE_ILLEGAL_INSTRUCTION	2
@@ -167,227 +154,6 @@
 #define RISCV_PGSHIFT 12
 #define RISCV_PGSIZE BIT(RISCV_PGSHIFT)
 
-/* CSR numbers */
-#define CSR_FFLAGS		0x1
-#define CSR_FRM			0x2
-#define CSR_FCSR		0x3
-
-#define CSR_SSTATUS		0x100
-#define CSR_SEDELEG		0x102
-#define CSR_SIDELEG		0x103
-#define CSR_SIE			0x104
-#define CSR_STVEC		0x105
-#define CSR_SCOUNTEREN		0x106
-#define CSR_SSCRATCH		0x140
-#define CSR_SEPC		0x141
-#define CSR_SCAUSE		0x142
-#define CSR_STVAL		0x143
-#define CSR_SIP			0x144
-#define CSR_SATP		0x180
-
-#define CSR_MSTATUS		0x300
-#define CSR_MISA		0x301
-#define CSR_MEDELEG		0x302
-#define CSR_MIDELEG		0x303
-#define CSR_MIE			0x304
-#define CSR_MTVEC		0x305
-#define CSR_MCOUNTEREN		0x306
-#define CSR_MHPMEVENT3		0x323
-#define CSR_MHPMEVENT4		0x324
-#define CSR_MHPMEVENT5		0x325
-#define CSR_MHPMEVENT6		0x326
-#define CSR_MHPMEVENT7		0x327
-#define CSR_MHPMEVENT8		0x328
-#define CSR_MHPMEVENT9		0x329
-#define CSR_MHPMEVENT10		0x32a
-#define CSR_MHPMEVENT11		0x32b
-#define CSR_MHPMEVENT12		0x32c
-#define CSR_MHPMEVENT13		0x32d
-#define CSR_MHPMEVENT14		0x32e
-#define CSR_MHPMEVENT15		0x32f
-#define CSR_MHPMEVENT16		0x330
-#define CSR_MHPMEVENT17		0x331
-#define CSR_MHPMEVENT18		0x332
-#define CSR_MHPMEVENT19		0x333
-#define CSR_MHPMEVENT20		0x334
-#define CSR_MHPMEVENT21		0x335
-#define CSR_MHPMEVENT22		0x336
-#define CSR_MHPMEVENT23		0x337
-#define CSR_MHPMEVENT24		0x338
-#define CSR_MHPMEVENT25		0x339
-#define CSR_MHPMEVENT26		0x33a
-#define CSR_MHPMEVENT27		0x33b
-#define CSR_MHPMEVENT28		0x33c
-#define CSR_MHPMEVENT29		0x33d
-#define CSR_MHPMEVENT30		0x33e
-#define CSR_MHPMEVENT31		0x33f
-#define CSR_MSCRATCH		0x340
-#define CSR_MEPC		0x341
-#define CSR_MCAUSE		0x342
-#define CSR_MTVAL		0x343
-#define CSR_MIP			0x344
-#define CSR_PMPCFG0		0x3a0
-#define CSR_PMPCFG1		0x3a1
-#define CSR_PMPCFG2		0x3a2
-#define CSR_PMPCFG3		0x3a3
-#define CSR_PMPADDR0		0x3b0
-#define CSR_PMPADDR1		0x3b1
-#define CSR_PMPADDR2		0x3b2
-#define CSR_PMPADDR3		0x3b3
-#define CSR_PMPADDR4		0x3b4
-#define CSR_PMPADDR5		0x3b5
-#define CSR_PMPADDR6		0x3b6
-#define CSR_PMPADDR7		0x3b7
-#define CSR_PMPADDR8		0x3b8
-#define CSR_PMPADDR9		0x3b9
-#define CSR_PMPADDR10		0x3ba
-#define CSR_PMPADDR11		0x3bb
-#define CSR_PMPADDR12		0x3bc
-#define CSR_PMPADDR13		0x3bd
-#define CSR_PMPADDR14		0x3be
-#define CSR_PMPADDR15		0x3bf
-
-#define CSR_TSELECT		0x7a0
-#define CSR_TDATA1		0x7a1
-#define CSR_TDATA2		0x7a2
-#define CSR_TDATA3		0x7a3
-#define CSR_DCSR		0x7b0
-#define CSR_DPC			0x7b1
-#define CSR_DSCRATCH		0x7b2
-
-#define CSR_MCYCLE		0xb00
-#define CSR_MINSTRET		0xb02
-#define CSR_MHPMCOUNTER3	0xb03
-#define CSR_MHPMCOUNTER4	0xb04
-#define CSR_MHPMCOUNTER5	0xb05
-#define CSR_MHPMCOUNTER6	0xb06
-#define CSR_MHPMCOUNTER7	0xb07
-#define CSR_MHPMCOUNTER8	0xb08
-#define CSR_MHPMCOUNTER9	0xb09
-#define CSR_MHPMCOUNTER10	0xb0a
-#define CSR_MHPMCOUNTER11	0xb0b
-#define CSR_MHPMCOUNTER12	0xb0c
-#define CSR_MHPMCOUNTER13	0xb0d
-#define CSR_MHPMCOUNTER14	0xb0e
-#define CSR_MHPMCOUNTER15	0xb0f
-#define CSR_MHPMCOUNTER16	0xb10
-#define CSR_MHPMCOUNTER17	0xb11
-#define CSR_MHPMCOUNTER18	0xb12
-#define CSR_MHPMCOUNTER19	0xb13
-#define CSR_MHPMCOUNTER20	0xb14
-#define CSR_MHPMCOUNTER21	0xb15
-#define CSR_MHPMCOUNTER22	0xb16
-#define CSR_MHPMCOUNTER23	0xb17
-#define CSR_MHPMCOUNTER24	0xb18
-#define CSR_MHPMCOUNTER25	0xb19
-#define CSR_MHPMCOUNTER26	0xb1a
-#define CSR_MHPMCOUNTER27	0xb1b
-#define CSR_MHPMCOUNTER28	0xb1c
-#define CSR_MHPMCOUNTER29	0xb1d
-#define CSR_MHPMCOUNTER30	0xb1e
-#define CSR_MHPMCOUNTER31	0xb1f
-#define CSR_MCYCLEH		0xb80
-#define CSR_MINSTRETH		0xb82
-#define CSR_MHPMCOUNTER3H	0xb83
-#define CSR_MHPMCOUNTER4H	0xb84
-#define CSR_MHPMCOUNTER5H	0xb85
-#define CSR_MHPMCOUNTER6H	0xb86
-#define CSR_MHPMCOUNTER7H	0xb87
-#define CSR_MHPMCOUNTER8H	0xb88
-#define CSR_MHPMCOUNTER9H	0xb89
-#define CSR_MHPMCOUNTER10H	0xb8a
-#define CSR_MHPMCOUNTER11H	0xb8b
-#define CSR_MHPMCOUNTER12H	0xb8c
-#define CSR_MHPMCOUNTER13H	0xb8d
-#define CSR_MHPMCOUNTER14H	0xb8e
-#define CSR_MHPMCOUNTER15H	0xb8f
-#define CSR_MHPMCOUNTER16H	0xb90
-#define CSR_MHPMCOUNTER17H	0xb91
-#define CSR_MHPMCOUNTER18H	0xb92
-#define CSR_MHPMCOUNTER19H	0xb93
-#define CSR_MHPMCOUNTER20H	0xb94
-#define CSR_MHPMCOUNTER21H	0xb95
-#define CSR_MHPMCOUNTER22H	0xb96
-#define CSR_MHPMCOUNTER23H	0xb97
-#define CSR_MHPMCOUNTER24H	0xb98
-#define CSR_MHPMCOUNTER25H	0xb99
-#define CSR_MHPMCOUNTER26H	0xb9a
-#define CSR_MHPMCOUNTER27H	0xb9b
-#define CSR_MHPMCOUNTER28H	0xb9c
-#define CSR_MHPMCOUNTER29H	0xb9d
-#define CSR_MHPMCOUNTER30H	0xb9e
-#define CSR_MHPMCOUNTER31H	0xb9f
-
-#define CSR_CYCLE		0xc00
-#define CSR_TIME		0xc01
-#define CSR_INSTRET		0xc02
-#define CSR_HPMCOUNTER3		0xc03
-#define CSR_HPMCOUNTER4		0xc04
-#define CSR_HPMCOUNTER5		0xc05
-#define CSR_HPMCOUNTER6		0xc06
-#define CSR_HPMCOUNTER7		0xc07
-#define CSR_HPMCOUNTER8		0xc08
-#define CSR_HPMCOUNTER9		0xc09
-#define CSR_HPMCOUNTER10	0xc0a
-#define CSR_HPMCOUNTER11	0xc0b
-#define CSR_HPMCOUNTER12	0xc0c
-#define CSR_HPMCOUNTER13	0xc0d
-#define CSR_HPMCOUNTER14	0xc0e
-#define CSR_HPMCOUNTER15	0xc0f
-#define CSR_HPMCOUNTER16	0xc10
-#define CSR_HPMCOUNTER17	0xc11
-#define CSR_HPMCOUNTER18	0xc12
-#define CSR_HPMCOUNTER19	0xc13
-#define CSR_HPMCOUNTER20	0xc14
-#define CSR_HPMCOUNTER21	0xc15
-#define CSR_HPMCOUNTER22	0xc16
-#define CSR_HPMCOUNTER23	0xc17
-#define CSR_HPMCOUNTER24	0xc18
-#define CSR_HPMCOUNTER25	0xc19
-#define CSR_HPMCOUNTER26	0xc1a
-#define CSR_HPMCOUNTER27	0xc1b
-#define CSR_HPMCOUNTER28	0xc1c
-#define CSR_HPMCOUNTER29	0xc1d
-#define CSR_HPMCOUNTER30	0xc1e
-#define CSR_HPMCOUNTER31	0xc1f
-#define CSR_CYCLEH		0xc80
-#define CSR_TIMEH		0xc81
-#define CSR_INSTRETH		0xc82
-#define CSR_HPMCOUNTER3H	0xc83
-#define CSR_HPMCOUNTER4H	0xc84
-#define CSR_HPMCOUNTER5H	0xc85
-#define CSR_HPMCOUNTER6H	0xc86
-#define CSR_HPMCOUNTER7H	0xc87
-#define CSR_HPMCOUNTER8H	0xc88
-#define CSR_HPMCOUNTER9H	0xc89
-#define CSR_HPMCOUNTER10H	0xc8a
-#define CSR_HPMCOUNTER11H	0xc8b
-#define CSR_HPMCOUNTER12H	0xc8c
-#define CSR_HPMCOUNTER13H	0xc8d
-#define CSR_HPMCOUNTER14H	0xc8e
-#define CSR_HPMCOUNTER15H	0xc8f
-#define CSR_HPMCOUNTER16H	0xc90
-#define CSR_HPMCOUNTER17H	0xc91
-#define CSR_HPMCOUNTER18H	0xc92
-#define CSR_HPMCOUNTER19H	0xc93
-#define CSR_HPMCOUNTER20H	0xc94
-#define CSR_HPMCOUNTER21H	0xc95
-#define CSR_HPMCOUNTER22H	0xc96
-#define CSR_HPMCOUNTER23H	0xc97
-#define CSR_HPMCOUNTER24H	0xc98
-#define CSR_HPMCOUNTER25H	0xc99
-#define CSR_HPMCOUNTER26H	0xc9a
-#define CSR_HPMCOUNTER27H	0xc9b
-#define CSR_HPMCOUNTER28H	0xc9c
-#define CSR_HPMCOUNTER29H	0xc9d
-#define CSR_HPMCOUNTER30H	0xc9e
-#define CSR_HPMCOUNTER31H	0xc9f
-
-#define CSR_MVENDORID		0xf11
-#define CSR_MARCHID		0xf12
-#define CSR_MIMPID		0xf13
-#define CSR_MHARTID		0xf14
-
 #endif /* __riscv */
 
 #endif /* RISCV_CSR_ENCODING_H */
diff --git a/doc/board/sifive/fu540.rst b/doc/board/sifive/fu540.rst
index 594f1fed9d..7807f5b2c1 100644
--- a/doc/board/sifive/fu540.rst
+++ b/doc/board/sifive/fu540.rst
@@ -17,6 +17,8 @@ The support for following drivers are already enabled:
 1. SiFive UART Driver.
 2. SiFive PRCI Driver for clock.
 3. Cadence MACB ethernet driver for networking support.
+4. SiFive SPI Driver.
+5. MMC SPI Driver for MMC/SD support.
 
 TODO:
 
@@ -48,14 +50,22 @@ Flashing
 
 The current U-Boot port is supported in S-mode only and loaded from DRAM.
 
-A prior stage (M-mode) firmware/bootloader (e.g OpenSBI or BBL) is required to
-load the u-boot.bin into memory and provide runtime services. The u-boot.bin
-can be given as a payload to the prior stage (M-mode) firmware/bootloader.
+A prior stage M-mode firmware/bootloader (e.g OpenSBI) is required to
+boot the u-boot.bin in S-mode and provide M-mode runtime services.
 
-The description of steps required to build the firmware is beyond the scope of
-this document. Please refer OpenSBI or BBL documenation.
+Currently, the u-boot.bin is used as a payload of the OpenSBI FW_PAYLOAD
+firmware. We need to compile OpenSBI with below command:
+
+.. code-block:: none
+
+    make PLATFORM=sifive/fu540 FW_PAYLOAD_PATH=<path to u-boot.bin> FW_PAYLOAD_FDT_PATH=<path to hifive-unleashed-a00.dtb from Linux>
+
+(Note: Prefer hifive-unleashed-a00.dtb from Linux-5.3 or higher)
+(Note: Linux-5.2 is also fine but it does not have ethernet DT node)
+
+More detailed description of steps required to build FW_PAYLOAD firmware
+is beyond the scope of this document. Please refer OpenSBI documenation.
 (Note: OpenSBI git repo is at https://github.com/riscv/opensbi.git)
-(Note: BBL git repo is at https://github.com/riscv/riscv-pk.git)
 
 Once the prior stage firmware/bootloader binary is generated, it should be
 copied to the first partition of the sdcard.
@@ -73,53 +83,70 @@ Sample boot log from HiFive Unleashed board
 
 .. code-block:: none
 
-   U-Boot 2019.01-00019-gc7953536-dirty (Jan 22 2019 - 11:05:40 -0800)
+   U-Boot 2019.07-00024-g350ff02f5b (Jul 22 2019 - 11:45:02 +0530)
 
    CPU:   rv64imafdc
-   Model: sifive,hifive-unleashed-a00
+   Model: SiFive HiFive Unleashed A00
    DRAM:  8 GiB
+   MMC:   spi@10050000:mmc@0: 0
    In:    serial@10010000
    Out:   serial@10010000
    Err:   serial@10010000
-   Net:
-   Warning: ethernet@10090000 (eth0) using random MAC address - b6:75:4d:48:50:94
-   eth0: ethernet@10090000
+   Net:   eth0: ethernet@10090000
    Hit any key to stop autoboot:  0
    => version
-   U-Boot 2019.01-00019-gc7953536-dirty (Jan 22 2019 - 11:05:40 -0800)
+   U-Boot 2019.07-00024-g350ff02f5b (Jul 22 2019 - 11:45:02 +0530)
 
    riscv64-linux-gcc.br_real (Buildroot 2018.11-rc2-00003-ga0787e9) 8.2.0
    GNU ld (GNU Binutils) 2.31.1
+   => mmc info
+   Device: spi@10050000:mmc@0
+   Manufacturer ID: 3
+   OEM: 5344
+   Name: SU08G
+   Bus Speed: 20000000
+   Mode: SD Legacy
+   Rd Block Len: 512
+   SD version 2.0
+   High Capacity: Yes
+   Capacity: 7.4 GiB
+   Bus Width: 1-bit
+   Erase Group Size: 512 Bytes
+   => mmc part
+
+   Partition Map for MMC device 0  --   Partition Type: EFI
+
+   Part    Start LBA       End LBA         Name
+           Attributes
+           Type GUID
+           Partition GUID
+     1     0x00000800      0x000107ff      "bootloader"
+           attrs:  0x0000000000000000
+           type:   2e54b353-1271-4842-806f-e436d6af6985
+           guid:   393bbd36-7111-491c-9869-ce24008f6403
+     2     0x00040800      0x00ecdfde      ""
+           attrs:  0x0000000000000000
+           type:   0fc63daf-8483-4772-8e79-3d69d8477de4
+           guid:   7fc9a949-5480-48c7-b623-04923080757f
 
 Now you can configure your networking, tftp server and use tftp boot method to
 load uImage.
 
 .. code-block:: none
 
-   => setenv ethaddr 70:B3:D5:92:F0:C2
-   => setenv ipaddr 10.196.157.189
-   => setenv serverip 10.11.143.218
-   => setenv gatewayip 10.196.156.1
+   => setenv ipaddr 10.206.7.133
    => setenv netmask 255.255.252.0
-   => bdinfo
-   boot_params = 0x0000000000000000
-   DRAM bank   = 0x0000000000000000
-   -> start    = 0x0000000080000000
-   -> size     = 0x0000000200000000
-   relocaddr   = 0x00000000fff90000
-   reloc off   = 0x000000007fd90000
-   ethaddr     = 70:B3:D5:92:F0:C2
-   IP addr     = 10.196.157.189
-   baudrate    = 115200 bps
-   => tftpboot uImage
+   => setenv serverip 10.206.4.143
+   => setenv gateway 10.206.4.1
+   => tftpboot ${kernel_addr_r} /sifive/fu540/Image
    ethernet@10090000: PHY present at 0
    ethernet@10090000: Starting autonegotiation...
    ethernet@10090000: Autonegotiation complete
-   ethernet@10090000: link up, 1000Mbps full-duplex (lpa: 0x3800)
+   ethernet@10090000: link up, 1000Mbps full-duplex (lpa: 0x3c00)
    Using ethernet@10090000 device
-   TFTP from server 10.11.143.218; our IP address is 10.196.157.189; sending through gateway 10.196.156.1
-   Filename 'uImage'.
-   Load address: 0x80200000
+   TFTP from server 10.206.4.143; our IP address is 10.206.7.133
+   Filename '/sifive/fu540/Image'.
+   Load address: 0x84000000
    Loading: #################################################################
             #################################################################
             #################################################################
@@ -146,175 +173,196 @@ load uImage.
             #################################################################
             #################################################################
             #################################################################
+            ##########################################
+            1.2 MiB/s
+   done
+   Bytes transferred = 8867100 (874d1c hex)
+   => tftpboot ${ramdisk_addr_r} /sifive/fu540/uRamdisk
+   ethernet@10090000: PHY present at 0
+   ethernet@10090000: Starting autonegotiation...
+   ethernet@10090000: Autonegotiation complete
+   ethernet@10090000: link up, 1000Mbps full-duplex (lpa: 0x3c00)
+   Using ethernet@10090000 device
+   TFTP from server 10.206.4.143; our IP address is 10.206.7.133
+   Filename '/sifive/fu540/uRamdisk'.
+   Load address: 0x88300000
+   Loading: #################################################################
             #################################################################
             #################################################################
             #################################################################
             #################################################################
             #################################################################
             #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            #################################################################
-            ##########################################################
-            2.5 MiB/s
+            ##############
+            418.9 KiB/s
+   done
+   Bytes transferred = 2398272 (249840 hex)
+   => tftpboot ${fdt_addr_r} /sifive/fu540/hifive-unleashed-a00.dtb
+   ethernet@10090000: PHY present at 0
+   ethernet@10090000: Starting autonegotiation...
+   ethernet@10090000: Autonegotiation complete
+   ethernet@10090000: link up, 1000Mbps full-duplex (lpa: 0x7c00)
+   Using ethernet@10090000 device
+   TFTP from server 10.206.4.143; our IP address is 10.206.7.133
+   Filename '/sifive/fu540/hifive-unleashed-a00.dtb'.
+   Load address: 0x88000000
+   Loading: ##
+            1000 Bytes/s
    done
-   Bytes transferred = 14939132 (e3f3fc hex)
-   => bootm 0x80200000 - 0x82200000
-   ## Booting kernel from Legacy Image at 80200000 ...
-      Image Name:   Linux
-      Image Type:   RISC-V Linux Kernel Image (uncompressed)
-      Data Size:    14939068 Bytes = 14.2 MiB
-      Load Address: 80200000
-      Entry Point:  80200000
+   Bytes transferred = 5614 (15ee hex)
+   => setenv bootargs "root=/dev/ram rw console=ttySIF0 ip=dhcp earlycon=sbi"
+   => booti ${kernel_addr_r} ${ramdisk_addr_r} ${fdt_addr_r}
+   ## Loading init Ramdisk from Legacy Image at 88300000 ...
+      Image Name:   Linux RootFS
+      Image Type:   RISC-V Linux RAMDisk Image (uncompressed)
+      Data Size:    2398208 Bytes = 2.3 MiB
+      Load Address: 00000000
+      Entry Point:  00000000
       Verifying Checksum ... OK
-   ## Flattened Device Tree blob at 82200000
-      Booting using the fdt blob at 0x82200000
-      Loading Kernel Image ... OK
-      Using Device Tree in place at 0000000082200000, end 0000000082205c69
+   ## Flattened Device Tree blob at 88000000
+      Booting using the fdt blob at 0x88000000
+      Using Device Tree in place at 0000000088000000, end 00000000880045ed
 
    Starting kernel ...
 
    [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
-   [    0.000000] Linux version 5.0.0-rc1-00020-g4b51f736 (atish@jedi-01) (gcc version 7.2.0 (GCC)) #262 SMP Mon Jan 21 17:39:27 PST 2019
-   [    0.000000] initrd not found or empty - disabling initrd
+   [    0.000000] Linux version 5.3.0-rc1-00003-g460ac558152f (anup@anup-lab-machine) (gcc version 8.2.0 (Buildroot 2018.11-rc2-00003-ga0787e9)) #6 SMP Mon Jul 22 10:01:01 IST 2019
+   [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
+   [    0.000000] printk: bootconsole [sbi0] enabled
+   [    0.000000] Initial ramdisk at: 0x(____ptrval____) (2398208 bytes)
    [    0.000000] Zone ranges:
    [    0.000000]   DMA32    [mem 0x0000000080200000-0x00000000ffffffff]
-   [    0.000000]   Normal   [mem 0x0000000100000000-0x000027ffffffffff]
+   [    0.000000]   Normal   [mem 0x0000000100000000-0x000000027fffffff]
    [    0.000000] Movable zone start for each node
    [    0.000000] Early memory node ranges
    [    0.000000]   node   0: [mem 0x0000000080200000-0x000000027fffffff]
    [    0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x000000027fffffff]
    [    0.000000] software IO TLB: mapped [mem 0xfbfff000-0xfffff000] (64MB)
-   [    0.000000] CPU with hartid=0 has a non-okay status of "masked"
-   [    0.000000] CPU with hartid=0 has a non-okay status of "masked"
+   [    0.000000] CPU with hartid=0 is not available
+   [    0.000000] CPU with hartid=0 is not available
    [    0.000000] elf_hwcap is 0x112d
-   [    0.000000] percpu: Embedded 15 pages/cpu @(____ptrval____) s29720 r0 d31720 u61440
+   [    0.000000] percpu: Embedded 18 pages/cpu s34584 r8192 d30952 u73728
    [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 2067975
-   [    0.000000] Kernel command line: earlyprintk
-   [    0.000000] Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes)
-   [    0.000000] Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes)
+   [    0.000000] Kernel command line: root=/dev/ram rw console=ttySIF0 ip=dhcp earlycon=sbi
+   [    0.000000] Dentry cache hash table entries: 1048576 (order: 11, 8388608 bytes, linear)
+   [    0.000000] Inode-cache hash table entries: 524288 (order: 10, 4194304 bytes, linear)
    [    0.000000] Sorting __ex_table...
-   [    0.000000] Memory: 8178760K/8386560K available (3309K kernel code, 248K rwdata, 872K rodata, 9381K init, 763K bss, 207800K reserved, 0K cma-reserved)
+   [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
+   [    0.000000] Memory: 8182308K/8386560K available (5916K kernel code, 368K rwdata, 1840K rodata, 213K init, 304K bss, 204252K reserved, 0K cma-reserved)
    [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
    [    0.000000] rcu: Hierarchical RCU implementation.
-   [    0.000000] rcu:     RCU event tracing is enabled.
    [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=4.
-   [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 10 jiffies.
+   [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
    [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
    [    0.000000] NR_IRQS: 0, nr_irqs: 0, preallocated irqs: 0
-   [    0.000000] plic: mapped 53 interrupts to 4 (out of 9) handlers.
+   [    0.000000] plic: mapped 53 interrupts with 4 handlers for 9 contexts.
    [    0.000000] riscv_timer_init_dt: Registering clocksource cpuid [0] hartid [1]
    [    0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x1d854df40, max_idle_ns: 3526361616960 ns
-   [    0.000008] sched_clock: 64 bits at 1000kHz, resolution 1000ns, wraps every 2199023255500ns
-   [    0.000221] Console: colour dummy device 80x25
-   [    0.000902] printk: console [tty0] enabled
-   [    0.000963] Calibrating delay loop (skipped), value calculated using timer frequency.. 2.00 BogoMIPS (lpj=10000)
-   [    0.001034] pid_max: default: 32768 minimum: 301
-   [    0.001541] Mount-cache hash table entries: 16384 (order: 5, 131072 bytes)
-   [    0.001912] Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes)
-   [    0.003542] rcu: Hierarchical SRCU implementation.
-   [    0.004347] smp: Bringing up secondary CPUs ...
-   [    1.040259] CPU1: failed to come online
-   [    2.080483] CPU2: failed to come online
-   [    3.120699] CPU3: failed to come online
-   [    3.120765] smp: Brought up 1 node, 1 CPU
-   [    3.121923] devtmpfs: initialized
-   [    3.124649] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
-   [    3.124727] futex hash table entries: 1024 (order: 4, 65536 bytes)
-   [    3.125346] random: get_random_u32 called from bucket_table_alloc+0x72/0x172 with crng_init=0
-   [    3.125578] NET: Registered protocol family 16
-   [    3.126400] sifive-u54-prci 10000000.prci: Registered U54 core clocks
-   [    3.126649] sifive-gemgxl-mgmt 100a0000.cadence-gemgxl-mgmt: Registered clock switch 'cadence-gemgxl-mgmt'
-   [    3.135572] vgaarb: loaded
-   [    3.135858] SCSI subsystem initialized
-   [    3.136193] usbcore: registered new interface driver usbfs
-   [    3.136266] usbcore: registered new interface driver hub
-   [    3.136348] usbcore: registered new device driver usb
-   [    3.136446] pps_core: LinuxPPS API ver. 1 registered
-   [    3.136484] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
-   [    3.136575] PTP clock support registered
-   [    3.137256] clocksource: Switched to clocksource riscv_clocksource
-   [    3.142711] NET: Registered protocol family 2
-   [    3.143322] tcp_listen_portaddr_hash hash table entries: 4096 (order: 4, 65536 bytes)
-   [    3.143634] TCP established hash table entries: 65536 (order: 7, 524288 bytes)
-   [    3.145799] TCP bind hash table entries: 65536 (order: 8, 1048576 bytes)
-   [    3.149121] TCP: Hash tables configured (established 65536 bind 65536)
-   [    3.149591] UDP hash table entries: 4096 (order: 5, 131072 bytes)
-   [    3.150094] UDP-Lite hash table entries: 4096 (order: 5, 131072 bytes)
-   [    3.150781] NET: Registered protocol family 1
-   [    3.230693] workingset: timestamp_bits=62 max_order=21 bucket_order=0
-   [    3.241224] io scheduler mq-deadline registered
-   [    3.241269] io scheduler kyber registered
-   [    3.242143] sifive_gpio 10060000.gpio: SiFive GPIO chip registered 16 GPIOs
-   [    3.242357] pwm-sifivem 10020000.pwm: Unable to find controller clock
-   [    3.242439] pwm-sifivem 10021000.pwm: Unable to find controller clock
-   [    3.243228] xilinx-pcie 2000000000.pci: PCIe Link is DOWN
-   [    3.243289] xilinx-pcie 2000000000.pci: host bridge /soc/pci@2000000000 ranges:
-   [    3.243360] xilinx-pcie 2000000000.pci:   No bus range found for /soc/pci@2000000000, using [bus 00-ff]
-   [    3.243447] xilinx-pcie 2000000000.pci:   MEM 0x40000000..0x5fffffff -> 0x40000000
-   [    3.243591] xilinx-pcie 2000000000.pci: PCI host bridge to bus 0000:00
-   [    3.243636] pci_bus 0000:00: root bus resource [bus 00-ff]
-   [    3.243676] pci_bus 0000:00: root bus resource [mem 0x40000000-0x5fffffff]
-   [    3.276547] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
-   [    3.277689] 10010000.serial: ttySIF0 at MMIO 0x10010000 (irq = 39, base_baud = 0) is a SiFive UART v0
-   [    3.786963] printk: console [ttySIF0] enabled
-   [    3.791504] 10011000.serial: ttySIF1 at MMIO 0x10011000 (irq = 40, base_baud = 0) is a SiFive UART v0
-   [    3.801251] sifive_spi 10040000.spi: mapped; irq=41, cs=1
-   [    3.806362] m25p80 spi0.0: unrecognized JEDEC id bytes: 9d, 70, 19
-   [    3.812084] m25p80: probe of spi0.0 failed with error -2
-   [    3.817453] sifive_spi 10041000.spi: mapped; irq=42, cs=4
-   [    3.823027] sifive_spi 10050000.spi: mapped; irq=43, cs=1
-   [    3.828604] libphy: Fixed MDIO Bus: probed
-   [    3.832623] macb: GEM doesn't support hardware ptp.
-   [    3.837196] libphy: MACB_mii_bus: probed
-   [    4.041156] Microsemi VSC8541 SyncE 10090000.ethernet-ffffffff:00: attached PHY driver [Microsemi VSC8541 SyncE] (mii_bus:phy_addr=10090000.ethernet-ffffffff:00, irq=POLL)
-   [    4.055779] macb 10090000.ethernet eth0: Cadence GEM rev 0x10070109 at 0x10090000 irq 12 (70:b3:d5:92:f0:c2)
-   [    4.065780] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
-   [    4.072033] ehci-pci: EHCI PCI platform driver
-   [    4.076521] usbcore: registered new interface driver usb-storage
-   [    4.082843] softdog: initialized. soft_noboot=0 soft_margin=60 sec soft_panic=0 (nowayout=0)
-   [    4.127465] mmc_spi spi2.0: SD/MMC host mmc0, no DMA, no WP, no poweroff
-   [    4.133645] usbcore: registered new interface driver usbhid
-   [    4.138980] usbhid: USB HID core driver
-   [    4.143017] NET: Registered protocol family 17
-   [    4.147885] pwm-sifivem 10020000.pwm: SiFive PWM chip registered 4 PWMs
-   [    4.153945] pwm-sifivem 10021000.pwm: SiFive PWM chip registered 4 PWMs
-   [    4.186407] Freeing unused kernel memory: 9380K
-   [    4.190224] This architecture does not have kernel memory protection.
-   [    4.196609] Run /init as init process
-   Starting logging: OK
-   Starting mdev...
-   [    4.303785] mmc0: host does not support reading read-only switch, assuming write-enable
-   [    4.311109] mmc0: new SDHC card on SPI
-   [    4.317103] mmcblk0: mmc0:0000 SS08G 7.40 GiB
-   [    4.386471]  mmcblk0: p1 p2
-   sort: /sys/devices/platform/Fixed: No such file or directory
-   modprobe: can't change directory to '/lib/modules': No such file or directory
-   Initializing random[    4.759075] random: dd: uninitialized urandom read (512 bytes read)
-    number generator... done.
-   Starting network...
-   udhcpc (v1.24.2) started
-   Sending discover...
-   Sending discover...
-   [    7.927510] macb 10090000.ethernet eth0: link up (1000/Full)
-   Sending discover...
-   Sending select for 10.196.157.190...
-   Lease of 10.196.157.190 obtained, lease time 499743
-   deleting routers
-   adding dns 10.86.1.1
-   adding dns 10.86.2.1
-   /etc/init.d/S50dropbear
-   Starting dropbear sshd: [   12.772393] random: dropbear: uninitialized urandom read (32 bytes read)
-   OK
-
-   Welcome to Buildroot
-   buildroot login:
+   [    0.000006] sched_clock: 64 bits at 1000kHz, resolution 1000ns, wraps every 2199023255500ns
+   [    0.008559] Console: colour dummy device 80x25
+   [    0.012989] Calibrating delay loop (skipped), value calculated using timer frequency.. 2.00 BogoMIPS (lpj=4000)
+   [    0.023104] pid_max: default: 32768 minimum: 301
+   [    0.028273] Mount-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
+   [    0.035765] Mountpoint-cache hash table entries: 16384 (order: 5, 131072 bytes, linear)
+   [    0.045307] rcu: Hierarchical SRCU implementation.
+   [    0.049875] smp: Bringing up secondary CPUs ...
+   [    0.055729] smp: Brought up 1 node, 4 CPUs
+   [    0.060599] devtmpfs: initialized
+   [    0.064819] random: get_random_u32 called from bucket_table_alloc.isra.10+0x4e/0x160 with crng_init=0
+   [    0.073720] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
+   [    0.083176] futex hash table entries: 1024 (order: 4, 65536 bytes, linear)
+   [    0.090721] NET: Registered protocol family 16
+   [    0.106319] vgaarb: loaded
+   [    0.108670] SCSI subsystem initialized
+   [    0.112515] usbcore: registered new interface driver usbfs
+   [    0.117758] usbcore: registered new interface driver hub
+   [    0.123167] usbcore: registered new device driver usb
+   [    0.128905] clocksource: Switched to clocksource riscv_clocksource
+   [    0.141239] NET: Registered protocol family 2
+   [    0.145506] tcp_listen_portaddr_hash hash table entries: 4096 (order: 4, 65536 bytes, linear)
+   [    0.153754] TCP established hash table entries: 65536 (order: 7, 524288 bytes, linear)
+   [    0.163466] TCP bind hash table entries: 65536 (order: 8, 1048576 bytes, linear)
+   [    0.173468] TCP: Hash tables configured (established 65536 bind 65536)
+   [    0.179739] UDP hash table entries: 4096 (order: 5, 131072 bytes, linear)
+   [    0.186627] UDP-Lite hash table entries: 4096 (order: 5, 131072 bytes, linear)
+   [    0.194117] NET: Registered protocol family 1
+   [    0.198417] RPC: Registered named UNIX socket transport module.
+   [    0.203887] RPC: Registered udp transport module.
+   [    0.208664] RPC: Registered tcp transport module.
+   [    0.213429] RPC: Registered tcp NFSv4.1 backchannel transport module.
+   [    0.219944] PCI: CLS 0 bytes, default 64
+   [    0.224170] Unpacking initramfs...
+   [    0.262347] Freeing initrd memory: 2336K
+   [    0.266531] workingset: timestamp_bits=62 max_order=21 bucket_order=0
+   [    0.280406] NFS: Registering the id_resolver key type
+   [    0.284798] Key type id_resolver registered
+   [    0.289048] Key type id_legacy registered
+   [    0.293114] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
+   [    0.300262] NET: Registered protocol family 38
+   [    0.304432] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 254)
+   [    0.311862] io scheduler mq-deadline registered
+   [    0.316461] io scheduler kyber registered
+   [    0.356421] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
+   [    0.363004] 10010000.serial: ttySIF0 at MMIO 0x10010000 (irq = 4, base_baud = 0) is a SiFive UART v0
+   [    0.371468] printk: console [ttySIF0] enabled
+   [    0.371468] printk: console [ttySIF0] enabled
+   [    0.380223] printk: bootconsole [sbi0] disabled
+   [    0.380223] printk: bootconsole [sbi0] disabled
+   [    0.389589] 10011000.serial: ttySIF1 at MMIO 0x10011000 (irq = 1, base_baud = 0) is a SiFive UART v0
+   [    0.398680] [drm] radeon kernel modesetting enabled.
+   [    0.412395] loop: module loaded
+   [    0.415214] sifive_spi 10040000.spi: mapped; irq=3, cs=1
+   [    0.420628] sifive_spi 10050000.spi: mapped; irq=5, cs=1
+   [    0.425897] libphy: Fixed MDIO Bus: probed
+   [    0.429964] macb 10090000.ethernet: Registered clk switch 'sifive-gemgxl-mgmt'
+   [    0.436743] macb: GEM doesn't support hardware ptp.
+   [    0.441621] libphy: MACB_mii_bus: probed
+   [    0.601316] Microsemi VSC8541 SyncE 10090000.ethernet-ffffffff:00: attached PHY driver [Microsemi VSC8541 SyncE] (mii_bus:phy_addr=10090000.ethernet-ffffffff:00, irq=POLL)
+   [    0.615857] macb 10090000.ethernet eth0: Cadence GEM rev 0x10070109 at 0x10090000 irq 6 (70:b3:d5:92:f2:f3)
+   [    0.625634] e1000e: Intel(R) PRO/1000 Network Driver - 3.2.6-k
+   [    0.631381] e1000e: Copyright(c) 1999 - 2015 Intel Corporation.
+   [    0.637382] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
+   [    0.643799] ehci-pci: EHCI PCI platform driver
+   [    0.648261] ehci-platform: EHCI generic platform driver
+   [    0.653497] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
+   [    0.659599] ohci-pci: OHCI PCI platform driver
+   [    0.664055] ohci-platform: OHCI generic platform driver
+   [    0.669448] usbcore: registered new interface driver uas
+   [    0.674575] usbcore: registered new interface driver usb-storage
+   [    0.680642] mousedev: PS/2 mouse device common for all mice
+   [    0.709493] mmc_spi spi1.0: SD/MMC host mmc0, no DMA, no WP, no poweroff, cd polling
+   [    0.716615] usbcore: registered new interface driver usbhid
+   [    0.722023] usbhid: USB HID core driver
+   [    0.726738] NET: Registered protocol family 10
+   [    0.731359] Segment Routing with IPv6
+   [    0.734332] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
+   [    0.740687] NET: Registered protocol family 17
+   [    0.744660] Key type dns_resolver registered
+   [    0.806775] mmc0: host does not support reading read-only switch, assuming write-enable
+   [    0.814020] mmc0: new SDHC card on SPI
+   [    0.820137] mmcblk0: mmc0:0000 SU08G 7.40 GiB
+   [    0.850220]  mmcblk0: p1 p2
+   [    3.821524] macb 10090000.ethernet eth0: link up (1000/Full)
+   [    3.828938] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
+   [    3.848919] Sending DHCP requests .., OK
+   [    6.252076] IP-Config: Got DHCP answer from 10.206.4.1, my address is 10.206.7.133
+   [    6.259624] IP-Config: Complete:
+   [    6.262831]      device=eth0, hwaddr=70:b3:d5:92:f2:f3, ipaddr=10.206.7.133, mask=255.255.252.0, gw=10.206.4.1
+   [    6.272809]      host=dhcp-10-206-7-133, domain=sdcorp.global.sandisk.com, nis-domain=(none)
+   [    6.281228]      bootserver=10.206.126.11, rootserver=10.206.126.11, rootpath=
+   [    6.281232]      nameserver0=10.86.1.1, nameserver1=10.86.2.1
+   [    6.294179]      ntpserver0=10.86.1.1, ntpserver1=10.86.2.1
+   [    6.301026] Freeing unused kernel memory: 212K
+   [    6.304683] This architecture does not have kernel memory protection.
+   [    6.311121] Run /init as init process
+              _  _
+             | ||_|
+             | | _ ____  _   _  _  _
+             | || |  _ \| | | |\ \/ /
+             | || | | | | |_| |/    \
+             |_||_|_| |_|\____|\_/\_/
+
+                  Busybox Rootfs
+
+   Please press Enter to activate this console.
+   / #
diff --git a/drivers/serial/serial_sifive.c b/drivers/serial/serial_sifive.c
index fdfef69aaa..c142ccdf3d 100644
--- a/drivers/serial/serial_sifive.c
+++ b/drivers/serial/serial_sifive.c
@@ -22,6 +22,9 @@ DECLARE_GLOBAL_DATA_PTR;
 #define UART_TXCTRL_TXEN	0x1
 #define UART_RXCTRL_RXEN	0x1
 
+/* IP register */
+#define UART_IP_RXWM            0x2
+
 struct uart_sifive {
 	u32 txfifo;
 	u32 rxfifo;
@@ -34,7 +37,6 @@ struct uart_sifive {
 
 struct sifive_uart_platdata {
 	unsigned long clock;
-	int saved_input_char;
 	struct uart_sifive *regs;
 };
 
@@ -94,7 +96,7 @@ static int _sifive_serial_getc(struct uart_sifive *regs)
 		return -EAGAIN;
 	ch &= UART_RXFIFO_DATA;
 
-	return (!ch) ? -EAGAIN : ch;
+	return ch;
 }
 
 static int sifive_serial_setbrg(struct udevice *dev, int baudrate)
@@ -133,7 +135,6 @@ static int sifive_serial_probe(struct udevice *dev)
 	if (gd->flags & GD_FLG_RELOC)
 		return 0;
 
-	platdata->saved_input_char = 0;
 	_sifive_serial_init(platdata->regs);
 
 	return 0;
@@ -145,12 +146,6 @@ static int sifive_serial_getc(struct udevice *dev)
 	struct sifive_uart_platdata *platdata = dev_get_platdata(dev);
 	struct uart_sifive *regs = platdata->regs;
 
-	if (platdata->saved_input_char > 0) {
-		c = platdata->saved_input_char;
-		platdata->saved_input_char = 0;
-		return c;
-	}
-
 	while ((c = _sifive_serial_getc(regs)) == -EAGAIN) ;
 
 	return c;
@@ -171,14 +166,10 @@ static int sifive_serial_pending(struct udevice *dev, bool input)
 	struct sifive_uart_platdata *platdata = dev_get_platdata(dev);
 	struct uart_sifive *regs = platdata->regs;
 
-	if (input) {
-		if (platdata->saved_input_char > 0)
-			return 1;
-		platdata->saved_input_char = _sifive_serial_getc(regs);
-		return (platdata->saved_input_char > 0) ? 1 : 0;
-	} else {
+	if (input)
+		return (readl(&regs->ip) & UART_IP_RXWM);
+	else
 		return !!(readl(&regs->txfifo) & UART_TXFIFO_FULL);
-	}
 }
 
 static int sifive_serial_ofdata_to_platdata(struct udevice *dev)
diff --git a/tools/prelink-riscv.c b/tools/prelink-riscv.c
index 52eb78e9d0..b0467949eb 100644
--- a/tools/prelink-riscv.c
+++ b/tools/prelink-riscv.c
@@ -8,10 +8,6 @@
  * without fixup. Both RV32 and RV64 are supported.
  */
 
-#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__
-#error "Only little-endian host is supported"
-#endif
-
 #include <errno.h>
 #include <stdbool.h>
 #include <stdint.h>
@@ -25,6 +21,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <compiler.h>
 
 #ifndef EM_RISCV
 #define EM_RISCV 243
@@ -50,12 +47,28 @@ const char *argv0;
 		exit(EXIT_FAILURE); \
 	} while (0)
 
+#define PRELINK_BYTEORDER le
+#define PRELINK_INC_BITS 32
+#include "prelink-riscv.inc"
+#undef PRELINK_BYTEORDER
+#undef PRELINK_INC_BITS
+
+#define PRELINK_BYTEORDER le
+#define PRELINK_INC_BITS 64
+#include "prelink-riscv.inc"
+#undef PRELINK_BYTEORDER
+#undef PRELINK_INC_BITS
+
+#define PRELINK_BYTEORDER be
 #define PRELINK_INC_BITS 32
 #include "prelink-riscv.inc"
+#undef PRELINK_BYTEORDER
 #undef PRELINK_INC_BITS
 
+#define PRELINK_BYTEORDER be
 #define PRELINK_INC_BITS 64
 #include "prelink-riscv.inc"
+#undef PRELINK_BYTEORDER
 #undef PRELINK_INC_BITS
 
 int main(int argc, const char *const *argv)
@@ -91,11 +104,19 @@ int main(int argc, const char *const *argv)
 		die("Invalid ELF file %s", argv[1]);
 
 	bool is64 = e_ident[EI_CLASS] == ELFCLASS64;
-
-	if (is64)
-		prelink64(data);
-	else
-		prelink32(data);
+	bool isbe = e_ident[EI_DATA] == ELFDATA2MSB;
+
+	if (is64) {
+		if (isbe)
+			prelink_be64(data);
+		else
+			prelink_le64(data);
+	} else {
+		if (isbe)
+			prelink_be32(data);
+		else
+			prelink_le32(data);
+	}
 
 	return 0;
 }
diff --git a/tools/prelink-riscv.inc b/tools/prelink-riscv.inc
index d49258707d..8b40ec430a 100644
--- a/tools/prelink-riscv.inc
+++ b/tools/prelink-riscv.inc
@@ -12,9 +12,9 @@
 #define CONCAT(x, y) CONCAT_IMPL(x, y)
 #define CONCAT3(x, y, z) CONCAT(CONCAT(x, y), z)
 
-#define prelink_nn      CONCAT(prelink, PRELINK_INC_BITS)
+#define prelink_bonn    CONCAT3(prelink_, PRELINK_BYTEORDER, PRELINK_INC_BITS)
 #define uintnn_t        CONCAT3(uint, PRELINK_INC_BITS, _t)
-#define get_offset_nn   CONCAT(get_offset_, PRELINK_INC_BITS)
+#define get_offset_bonn CONCAT3(get_offset_, PRELINK_BYTEORDER, PRELINK_INC_BITS)
 #define Elf_Ehdr        CONCAT3(Elf, PRELINK_INC_BITS, _Ehdr)
 #define Elf_Phdr        CONCAT3(Elf, PRELINK_INC_BITS, _Phdr)
 #define Elf_Rela        CONCAT3(Elf, PRELINK_INC_BITS, _Rela)
@@ -23,34 +23,38 @@
 #define Elf_Addr        CONCAT3(Elf, PRELINK_INC_BITS, _Addr)
 #define ELF_R_TYPE      CONCAT3(ELF, PRELINK_INC_BITS, _R_TYPE)
 #define ELF_R_SYM       CONCAT3(ELF, PRELINK_INC_BITS, _R_SYM)
+#define target16_to_cpu CONCAT(PRELINK_BYTEORDER, 16_to_cpu)
+#define target32_to_cpu CONCAT(PRELINK_BYTEORDER, 32_to_cpu)
+#define target64_to_cpu CONCAT(PRELINK_BYTEORDER, 64_to_cpu)
+#define targetnn_to_cpu CONCAT3(PRELINK_BYTEORDER, PRELINK_INC_BITS, _to_cpu)
 
-static void* get_offset_nn (void* data, Elf_Phdr* phdrs, size_t phnum, Elf_Addr addr)
+static void* get_offset_bonn (void* data, Elf_Phdr* phdrs, size_t phnum, Elf_Addr addr)
 {
 	Elf_Phdr *p;
 
 	for (p = phdrs; p < phdrs + phnum; ++p)
-		if (p->p_vaddr <= addr && p->p_vaddr + p->p_memsz > addr)
-			return data + p->p_offset + (addr - p->p_vaddr);
+		if (targetnn_to_cpu(p->p_vaddr) <= addr && targetnn_to_cpu(p->p_vaddr) + targetnn_to_cpu(p->p_memsz) > addr)
+			return data + targetnn_to_cpu(p->p_offset) + (addr - targetnn_to_cpu(p->p_vaddr));
 
 	return NULL;
 }
 
-static void prelink_nn(void *data)
+static void prelink_bonn(void *data)
 {
 	Elf_Ehdr *ehdr = data;
 	Elf_Phdr *p;
 	Elf_Dyn *dyn;
 	Elf_Rela *r;
 
-	if (ehdr->e_machine != EM_RISCV)
+	if (target16_to_cpu(ehdr->e_machine) != EM_RISCV)
 		die("Machine type is not RISC-V");
 
-	Elf_Phdr *phdrs = data + ehdr->e_phoff;
+	Elf_Phdr *phdrs = data + targetnn_to_cpu(ehdr->e_phoff);
 
 	Elf_Dyn *dyns = NULL;
-	for (p = phdrs; p < phdrs + ehdr->e_phnum; ++p) {
-		if (p->p_type == PT_DYNAMIC) {
-			dyns = data + p->p_offset;
+	for (p = phdrs; p < phdrs + target16_to_cpu(ehdr->e_phnum); ++p) {
+		if (target32_to_cpu(p->p_type) == PT_DYNAMIC) {
+			dyns = data + targetnn_to_cpu(p->p_offset);
 			break;
 		}
 	}
@@ -62,14 +66,14 @@ static void prelink_nn(void *data)
 	size_t rela_count = 0;
 	Elf_Sym *dynsym = NULL;
 	for (dyn = dyns;; ++dyn) {
-		if (dyn->d_tag == DT_NULL)
+		if (targetnn_to_cpu(dyn->d_tag) == DT_NULL)
 			break;
-		else if (dyn->d_tag == DT_RELA)
-			rela_dyn = get_offset_nn(data, phdrs, ehdr->e_phnum, + dyn->d_un.d_ptr);
-		else if (dyn->d_tag == DT_RELASZ)
-			rela_count = dyn->d_un.d_val / sizeof(Elf_Rela);
-		else if (dyn->d_tag == DT_SYMTAB)
-			dynsym = get_offset_nn(data, phdrs, ehdr->e_phnum, + dyn->d_un.d_ptr);
+		else if (targetnn_to_cpu(dyn->d_tag) == DT_RELA)
+			rela_dyn = get_offset_bonn(data, phdrs, target16_to_cpu(ehdr->e_phnum), + targetnn_to_cpu(dyn->d_un.d_ptr));
+		else if (targetnn_to_cpu(dyn->d_tag) == DT_RELASZ)
+		  rela_count = targetnn_to_cpu(dyn->d_un.d_val) / sizeof(Elf_Rela);
+		else if (targetnn_to_cpu(dyn->d_tag) == DT_SYMTAB)
+			dynsym = get_offset_bonn(data, phdrs, target16_to_cpu(ehdr->e_phnum), + targetnn_to_cpu(dyn->d_un.d_ptr));
 
 	}
 
@@ -80,23 +84,23 @@ static void prelink_nn(void *data)
 		die("No .dynsym found");
 
 	for (r = rela_dyn; r < rela_dyn + rela_count; ++r) {
-		void* buf = get_offset_nn(data, phdrs, ehdr->e_phnum, r->r_offset);
+		void* buf = get_offset_bonn(data, phdrs, target16_to_cpu(ehdr->e_phnum), targetnn_to_cpu(r->r_offset));
 
 		if (buf == NULL)
 			continue;
 
-		if (ELF_R_TYPE(r->r_info) == R_RISCV_RELATIVE)
+		if (ELF_R_TYPE(targetnn_to_cpu(r->r_info)) == R_RISCV_RELATIVE)
 			*((uintnn_t*) buf) = r->r_addend;
-		else if (ELF_R_TYPE(r->r_info) == R_RISCV_32)
-			*((uint32_t*) buf) = dynsym[ELF_R_SYM(r->r_info)].st_value;
-		else if (ELF_R_TYPE(r->r_info) == R_RISCV_64)
-			*((uint64_t*) buf) = dynsym[ELF_R_SYM(r->r_info)].st_value;
+		else if (ELF_R_TYPE(targetnn_to_cpu(r->r_info)) == R_RISCV_32)
+			*((uint32_t*) buf) = dynsym[ELF_R_SYM(targetnn_to_cpu(r->r_info))].st_value;
+		else if (ELF_R_TYPE(targetnn_to_cpu(r->r_info)) == R_RISCV_64)
+			*((uint64_t*) buf) = dynsym[ELF_R_SYM(targetnn_to_cpu(r->r_info))].st_value;
 	}
 }
 
-#undef prelink_nn
+#undef prelink_bonn
 #undef uintnn_t
-#undef get_offset_nn
+#undef get_offset_bonn
 #undef Elf_Ehdr
 #undef Elf_Phdr
 #undef Elf_Rela
@@ -105,6 +109,10 @@ static void prelink_nn(void *data)
 #undef Elf_Addr
 #undef ELF_R_TYPE
 #undef ELF_R_SYM
+#undef target16_to_cpu
+#undef target32_to_cpu
+#undef target64_to_cpu
+#undef targetnn_to_cpu
 
 #undef CONCAT_IMPL
 #undef CONCAT