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-rw-r--r--arch/arm/mach-s3c/irq-s3c24xx-fiq.S112
1 files changed, 112 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/irq-s3c24xx-fiq.S b/arch/arm/mach-s3c/irq-s3c24xx-fiq.S
new file mode 100644
index 000000000..5d238d9a7
--- /dev/null
+++ b/arch/arm/mach-s3c/irq-s3c24xx-fiq.S
@@ -0,0 +1,112 @@
+/* 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 "map.h"
+#include "regs-irq.h"
+
+#include <linux/spi/s3c24xx-fiq.h>
+
+#define S3C2410_SPTDAT (0x10)
+#define S3C2410_SPRDAT (0x14)
+
+ .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