ARM: s3c24xx: move spi fiq handler into platform
The fiq handler needs access to some register definitions that
should not be used directly by device drivers.
Since this is closely related to the irqchip driver anyway,
move it into the same place.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[krzk: Add a header guard in include/linux/spi/s3c24xx-fiq.h, fix
SPDX comment style, update maintainer's entry]
Co-developed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200806182059.2431-23-krzk%40kernel.org
Acked-by: Mark Brown <broonie@kernel.org>
diff --git a/arch/arm/mach-s3c24xx/Makefile b/arch/arm/mach-s3c24xx/Makefile
index 3ad297b..b69eee2 100644
--- a/arch/arm/mach-s3c24xx/Makefile
+++ b/arch/arm/mach-s3c24xx/Makefile
@@ -9,6 +9,8 @@
obj-y += common.o
obj-y += irq-s3c24xx.o
+obj-$(CONFIG_SPI_S3C24XX_FIQ) += irq-s3c24xx-fiq.o
+obj-$(CONFIG_SPI_S3C24XX_FIQ) += irq-s3c24xx-fiq-exports.o
obj-$(CONFIG_CPU_S3C2410) += s3c2410.o
obj-$(CONFIG_S3C2410_PLL) += pll-s3c2410.o
diff --git a/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq-exports.c b/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq-exports.c
new file mode 100644
index 0000000..84cf863
--- /dev/null
+++ b/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq-exports.c
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/stddef.h>
+#include <linux/export.h>
+#include <linux/spi/s3c24xx-fiq.h>
+
+EXPORT_SYMBOL(s3c24xx_spi_fiq_rx);
+EXPORT_SYMBOL(s3c24xx_spi_fiq_txrx);
+EXPORT_SYMBOL(s3c24xx_spi_fiq_tx);
diff --git a/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq.S b/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq.S
new file mode 100644
index 0000000..2a84535
--- /dev/null
+++ b/arch/arm/mach-s3c24xx/irq-s3c24xx-fiq.S
@@ -0,0 +1,115 @@
+/* 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 <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)
+s3c24xx_spi_fix_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
+ subnes 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)
+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
+ subnes 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)
+s3c24xx_spi_fix_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
+ subnes 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
