tinyriscv-openocd/contrib/loaders/flash/mrvlqspi_write.S

233 lines
6.3 KiB
ArmAsm

/***************************************************************************
* Copyright (C) 2014 by Mahavir Jain <mjain@marvell.com> *
* *
* Adapted from (contrib/loaders/flash/lpcspifi_write.S): *
* Copyright (C) 2012 by George Harris *
* george@luminairecoffee.com *
* *
* 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; either version 2 of the License, or *
* (at your option) any later version. *
* *
* 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. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the *
* Free Software Foundation, Inc., *
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
***************************************************************************/
.text
.syntax unified
.cpu cortex-m3
.thumb
.thumb_func
/*
* For compilation:
* arm-none-eabi-gcc -mcpu=cortex-m3 -mthumb -c contrib/loaders/flash/mrvlqspi_write.S
* arm-none-eabi-objcopy -O binary mrvlqspi_write.o code.bin
* Copy code.bin into mrvlqspi flash driver
*/
/*
* Params :
* r0 = workarea start, status (out)
* r1 = workarea end
* r2 = target address (offset from flash base)
* r3 = count (bytes)
* r4 = page size
* r5 = qspi base address
* Clobbered:
* r7 - rp
* r8 - wp, tmp
* r9 - send/receive data
* r10 - current page end address
*/
#define CNTL 0x0
#define CONF 0x4
#define DOUT 0x8
#define DIN 0xc
#define INSTR 0x10
#define ADDR 0x14
#define RDMODE 0x18
#define HDRCNT 0x1c
#define DINCNT 0x20
#define SS_EN (1 << 0)
#define XFER_RDY (1 << 1)
#define RFIFO_EMPTY (1 << 4)
#define WFIFO_EMPTY (1 << 6)
#define WFIFO_FULL (1 << 7)
#define FIFO_FLUSH (1 << 9)
#define RW_EN (1 << 13)
#define XFER_STOP (1 << 14)
#define XFER_START (1 << 15)
#define INS_WRITE_ENABLE 0x06
#define INS_READ_STATUS 0x05
#define INS_PAGE_PROGRAM 0x02
init:
mov.w r10, #0x00
find_next_page_boundary:
add r10, r4 /* Increment to the next page */
cmp r10, r2
/* If we have not reached the next page boundary after the target address, keep going */
bls find_next_page_boundary
write_enable:
/* Flush read/write fifo's */
bl flush_fifo
/* Instruction byte 1 */
movs r8, #0x1
str r8, [r5, #HDRCNT]
/* Set write enable instruction */
movs r8, #INS_WRITE_ENABLE
str r8, [r5, #INSTR]
movs r9, #0x1
bl start_tx
bl stop_tx
page_program:
/* Instruction byte 1, Addr byte 3 */
movs r8, #0x31
str r8, [r5, #HDRCNT]
/* Todo: set addr and data pin to single */
write_address:
mov r8, r2
str r8, [r5, #ADDR]
/* Set page program instruction */
movs r8, #INS_PAGE_PROGRAM
str r8, [r5, #INSTR]
/* Start write transfer */
movs r9, #0x1
bl start_tx
wait_fifo:
ldr r8, [r0] /* read the write pointer */
cmp r8, #0 /* if it's zero, we're gonzo */
beq exit
ldr r7, [r0, #4] /* read the read pointer */
cmp r7, r8 /* wait until they are not equal */
beq wait_fifo
write:
ldrb r9, [r7], #0x01 /* Load one byte from the FIFO, increment the read pointer by 1 */
bl write_data /* send the byte to the flash chip */
cmp r7, r1 /* wrap the read pointer if it is at the end */
it cs
addcs r7, r0, #8 /* skip loader args */
str r7, [r0, #4] /* store the new read pointer */
subs r3, r3, #1 /* decrement count */
cmp r3, #0 /* Exit if we have written everything */
beq write_wait
add r2, #1 /* Increment flash address by 1 */
cmp r10, r2 /* See if we have reached the end of a page */
bne wait_fifo /* If not, keep writing bytes */
write_wait:
bl stop_tx /* Otherwise, end the command and keep going w/ the next page */
add r10, r4 /* Move up the end-of-page address by the page size*/
check_flash_busy: /* Wait for the flash to finish the previous page write */
/* Flush read/write fifo's */
bl flush_fifo
/* Instruction byte 1 */
movs r8, #0x1
str r8, [r5, #HDRCNT]
/* Continuous data in of status register */
movs r8, #0x0
str r8, [r5, #DINCNT]
/* Set write enable instruction */
movs r8, #INS_READ_STATUS
str r8, [r5, #INSTR]
/* Start read transfer */
movs r9, #0x0
bl start_tx
wait_flash_busy:
bl read_data
and.w r9, r9, #0x1
cmp r9, #0x0
bne.n wait_flash_busy
bl stop_tx
cmp r3, #0
bne.n write_enable /* If it is done, start a new page write */
b exit /* All data written, exit */
write_data: /* Send/receive 1 byte of data over QSPI */
ldr r8, [r5, #CNTL]
lsls r8, r8, #24
bmi.n write_data
str r9, [r5, #DOUT]
bx lr
read_data: /* Read 1 byte of data over QSPI */
ldr r8, [r5, #CNTL]
lsls r8, r8, #27
bmi.n read_data
ldr r9, [r5, #DIN]
bx lr
flush_fifo: /* Flush read write fifos */
ldr r8, [r5, #CONF]
orr.w r8, r8, #FIFO_FLUSH
str r8, [r5, #CONF]
flush_reset:
ldr r8, [r5, #CONF]
lsls r8, r8, #22
bmi.n flush_reset
bx lr
start_tx:
ldr r8, [r5, #CNTL]
orr.w r8, r8, #SS_EN
str r8, [r5, #CNTL]
xfer_rdy:
ldr r8, [r5, #CNTL]
lsls r8, r8, #30
bpl.n xfer_rdy
ldr r8, [r5, #CONF]
bfi r8, r9, #13, #1
orr.w r8, r8, #XFER_START
str r8, [r5, #CONF]
bx lr
stop_tx:
ldr r8, [r5, #CNTL]
lsls r8, r8, #30
bpl.n stop_tx
wfifo_wait:
ldr r8, [r5, #CNTL]
lsls r8, r8, #25
bpl.n wfifo_wait
ldr r8, [r5, #CONF]
orr.w r8, r8, #XFER_STOP
str r8, [r5, #CONF]
xfer_start:
ldr r8, [r5, #CONF]
lsls r8, r8, #16
bmi.n xfer_start
ss_disable:
# Disable SS_EN
ldr r8, [r5, #CNTL]
bic.w r8, r8, #SS_EN
str r8, [r5, #CNTL]
wait:
ldr r8, [r5, #CNTL]
lsls r8, r8, #30
bpl.n wait
bx lr
error:
movs r0, #0
str r0, [r2, #4] /* set rp = 0 on error */
exit:
mov r0, r6
bkpt #0x00
.end