111 lines
2.7 KiB
ArmAsm
111 lines
2.7 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/* linux/drivers/spi/spi_s3c24xx_fiq.S
|
|
*
|
|
* Copyright 2009 Simtec Electronics
|
|
* Ben Dooks <ben@simtec.co.uk>
|
|
*
|
|
* S3C24XX SPI - FIQ pseudo-DMA transfer code
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/assembler.h>
|
|
|
|
#include <mach/map.h>
|
|
#include <mach/regs-irq.h>
|
|
#include <plat/regs-spi.h>
|
|
|
|
#include "spi-s3c24xx-fiq.h"
|
|
|
|
.text
|
|
|
|
@ entry to these routines is as follows, with the register names
|
|
@ defined in fiq.h so that they can be shared with the C files which
|
|
@ setup the calling registers.
|
|
@
|
|
@ fiq_rirq The base of the IRQ registers to find S3C2410_SRCPND
|
|
@ fiq_rtmp Temporary register to hold tx/rx data
|
|
@ fiq_rspi The base of the SPI register block
|
|
@ fiq_rtx The tx buffer pointer
|
|
@ fiq_rrx The rx buffer pointer
|
|
@ fiq_rcount The number of bytes to move
|
|
|
|
@ each entry starts with a word entry of how long it is
|
|
@ and an offset to the irq acknowledgment word
|
|
|
|
ENTRY(s3c24xx_spi_fiq_rx)
|
|
.word fiq_rx_end - fiq_rx_start
|
|
.word fiq_rx_irq_ack - fiq_rx_start
|
|
fiq_rx_start:
|
|
ldr fiq_rtmp, fiq_rx_irq_ack
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
|
|
|
|
ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
|
|
strb fiq_rtmp, [ fiq_rrx ], #1
|
|
|
|
mov fiq_rtmp, #0xff
|
|
strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
|
|
|
|
subs fiq_rcount, fiq_rcount, #1
|
|
subsne pc, lr, #4 @@ return, still have work to do
|
|
|
|
@@ set IRQ controller so that next op will trigger IRQ
|
|
mov fiq_rtmp, #0
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]
|
|
subs pc, lr, #4
|
|
|
|
fiq_rx_irq_ack:
|
|
.word 0
|
|
fiq_rx_end:
|
|
|
|
ENTRY(s3c24xx_spi_fiq_txrx)
|
|
.word fiq_txrx_end - fiq_txrx_start
|
|
.word fiq_txrx_irq_ack - fiq_txrx_start
|
|
fiq_txrx_start:
|
|
|
|
ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
|
|
strb fiq_rtmp, [ fiq_rrx ], #1
|
|
|
|
ldr fiq_rtmp, fiq_txrx_irq_ack
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
|
|
|
|
ldrb fiq_rtmp, [ fiq_rtx ], #1
|
|
strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
|
|
|
|
subs fiq_rcount, fiq_rcount, #1
|
|
subsne pc, lr, #4 @@ return, still have work to do
|
|
|
|
mov fiq_rtmp, #0
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]
|
|
subs pc, lr, #4
|
|
|
|
fiq_txrx_irq_ack:
|
|
.word 0
|
|
|
|
fiq_txrx_end:
|
|
|
|
ENTRY(s3c24xx_spi_fiq_tx)
|
|
.word fiq_tx_end - fiq_tx_start
|
|
.word fiq_tx_irq_ack - fiq_tx_start
|
|
fiq_tx_start:
|
|
ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
|
|
|
|
ldr fiq_rtmp, fiq_tx_irq_ack
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
|
|
|
|
ldrb fiq_rtmp, [ fiq_rtx ], #1
|
|
strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
|
|
|
|
subs fiq_rcount, fiq_rcount, #1
|
|
subsne pc, lr, #4 @@ return, still have work to do
|
|
|
|
mov fiq_rtmp, #0
|
|
str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]
|
|
subs pc, lr, #4
|
|
|
|
fiq_tx_irq_ack:
|
|
.word 0
|
|
|
|
fiq_tx_end:
|
|
|
|
.end
|