1 /* linux/drivers/spi/spi_s3c24xx_fiq.S
3 * Copyright 2009 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
6 * S3C24XX SPI - FIQ pseudo-DMA transfer code
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/linkage.h>
14 #include <asm/assembler.h>
17 #include <mach/regs-irq.h>
18 #include <plat/regs-spi.h>
20 #include "spi-s3c24xx-fiq.h"
24 @ entry to these routines is as follows, with the register names
25 @ defined in fiq.h so that they can be shared with the C files which
26 @ setup the calling registers.
28 @ fiq_rirq The base of the IRQ registers to find S3C2410_SRCPND
29 @ fiq_rtmp Temporary register to hold tx/rx data
30 @ fiq_rspi The base of the SPI register block
31 @ fiq_rtx The tx buffer pointer
32 @ fiq_rrx The rx buffer pointer
33 @ fiq_rcount The number of bytes to move
35 @ each entry starts with a word entry of how long it is
36 @ and an offset to the irq acknowledgment word
38 ENTRY(s3c24xx_spi_fiq_rx)
39 .word fiq_rx_end - fiq_rx_start
40 .word fiq_rx_irq_ack - fiq_rx_start
42 ldr fiq_rtmp, fiq_rx_irq_ack
43 str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
45 ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
46 strb fiq_rtmp, [ fiq_rrx ], #1
49 strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
51 subs fiq_rcount, fiq_rcount, #1
52 subsne pc, lr, #4 @@ return, still have work to do
54 @@ set IRQ controller so that next op will trigger IRQ
56 str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]
63 ENTRY(s3c24xx_spi_fiq_txrx)
64 .word fiq_txrx_end - fiq_txrx_start
65 .word fiq_txrx_irq_ack - fiq_txrx_start
68 ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
69 strb fiq_rtmp, [ fiq_rrx ], #1
71 ldr fiq_rtmp, fiq_txrx_irq_ack
72 str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
74 ldrb fiq_rtmp, [ fiq_rtx ], #1
75 strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
77 subs fiq_rcount, fiq_rcount, #1
78 subsne pc, lr, #4 @@ return, still have work to do
81 str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]
89 ENTRY(s3c24xx_spi_fiq_tx)
90 .word fiq_tx_end - fiq_tx_start
91 .word fiq_tx_irq_ack - fiq_tx_start
93 ldrb fiq_rtmp, [ fiq_rspi, # S3C2410_SPRDAT ]
95 ldr fiq_rtmp, fiq_tx_irq_ack
96 str fiq_rtmp, [ fiq_rirq, # S3C2410_SRCPND - S3C24XX_VA_IRQ ]
98 ldrb fiq_rtmp, [ fiq_rtx ], #1
99 strb fiq_rtmp, [ fiq_rspi, # S3C2410_SPTDAT ]
101 subs fiq_rcount, fiq_rcount, #1
102 subsne pc, lr, #4 @@ return, still have work to do
105 str fiq_rtmp, [ fiq_rirq, # S3C2410_INTMOD - S3C24XX_VA_IRQ ]