Fixed MTP to work with TWRP

arch/arm/mach-rpc/Makefile

@@ -0,0 +1,7 @@
+#
+# Makefile for the linux kernel.
+#
+
+# Object file lists.
+
+obj-y			:= dma.o ecard.o fiq.o irq.o riscpc.o time.o

arch/arm/mach-rpc/Makefile.boot

@@ -0,0 +1,4 @@
+   zreladdr-y	+= 0x10008000
+params_phys-y	:= 0x10000100
+initrd_phys-y	:= 0x18000000
+

arch/arm/mach-rpc/dma.c

@@ -0,0 +1,389 @@
+/*
+ *  linux/arch/arm/mach-rpc/dma.c
+ *
+ *  Copyright (C) 1998 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  DMA functions specific to RiscPC architecture
+ */
+#include <linux/mman.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+
+#include <asm/page.h>
+#include <asm/dma.h>
+#include <asm/fiq.h>
+#include <asm/irq.h>
+#include <mach/hardware.h>
+#include <asm/uaccess.h>
+
+#include <asm/mach/dma.h>
+#include <asm/hardware/iomd.h>
+
+struct iomd_dma {
+	struct dma_struct	dma;
+	unsigned int		state;
+	unsigned long		base;		/* Controller base address */
+	int			irq;		/* Controller IRQ */
+	struct scatterlist	cur_sg;		/* Current controller buffer */
+	dma_addr_t		dma_addr;
+	unsigned int		dma_len;
+};
+
+#if 0
+typedef enum {
+	dma_size_8	= 1,
+	dma_size_16	= 2,
+	dma_size_32	= 4,
+	dma_size_128	= 16
+} dma_size_t;
+#endif
+
+#define TRANSFER_SIZE	2
+
+#define CURA	(0)
+#define ENDA	(IOMD_IO0ENDA - IOMD_IO0CURA)
+#define CURB	(IOMD_IO0CURB - IOMD_IO0CURA)
+#define ENDB	(IOMD_IO0ENDB - IOMD_IO0CURA)
+#define CR	(IOMD_IO0CR - IOMD_IO0CURA)
+#define ST	(IOMD_IO0ST - IOMD_IO0CURA)
+
+static void iomd_get_next_sg(struct scatterlist *sg, struct iomd_dma *idma)
+{
+	unsigned long end, offset, flags = 0;
+
+	if (idma->dma.sg) {
+		sg->dma_address = idma->dma_addr;
+		offset = sg->dma_address & ~PAGE_MASK;
+
+		end = offset + idma->dma_len;
+
+		if (end > PAGE_SIZE)
+			end = PAGE_SIZE;
+
+		if (offset + TRANSFER_SIZE >= end)
+			flags |= DMA_END_L;
+
+		sg->length = end - TRANSFER_SIZE;
+
+		idma->dma_len -= end - offset;
+		idma->dma_addr += end - offset;
+
+		if (idma->dma_len == 0) {
+			if (idma->dma.sgcount > 1) {
+				idma->dma.sg = sg_next(idma->dma.sg);
+				idma->dma_addr = idma->dma.sg->dma_address;
+				idma->dma_len = idma->dma.sg->length;
+				idma->dma.sgcount--;
+			} else {
+				idma->dma.sg = NULL;
+				flags |= DMA_END_S;
+			}
+		}
+	} else {
+		flags = DMA_END_S | DMA_END_L;
+		sg->dma_address = 0;
+		sg->length = 0;
+	}
+
+	sg->length |= flags;
+}
+
+static irqreturn_t iomd_dma_handle(int irq, void *dev_id)
+{
+	struct iomd_dma *idma = dev_id;
+	unsigned long base = idma->base;
+
+	do {
+		unsigned int status;
+
+		status = iomd_readb(base + ST);
+		if (!(status & DMA_ST_INT))
+			return IRQ_HANDLED;
+
+		if ((idma->state ^ status) & DMA_ST_AB)
+			iomd_get_next_sg(&idma->cur_sg, idma);
+
+		switch (status & (DMA_ST_OFL | DMA_ST_AB)) {
+		case DMA_ST_OFL:			/* OIA */
+		case DMA_ST_AB:				/* .IB */
+			iomd_writel(idma->cur_sg.dma_address, base + CURA);
+			iomd_writel(idma->cur_sg.length, base + ENDA);
+			idma->state = DMA_ST_AB;
+			break;
+
+		case DMA_ST_OFL | DMA_ST_AB:		/* OIB */
+		case 0:					/* .IA */
+			iomd_writel(idma->cur_sg.dma_address, base + CURB);
+			iomd_writel(idma->cur_sg.length, base + ENDB);
+			idma->state = 0;
+			break;
+		}
+
+		if (status & DMA_ST_OFL &&
+		    idma->cur_sg.length == (DMA_END_S|DMA_END_L))
+			break;
+	} while (1);
+
+	idma->state = ~DMA_ST_AB;
+	disable_irq(irq);
+
+	return IRQ_HANDLED;
+}
+
+static int iomd_request_dma(unsigned int chan, dma_t *dma)
+{
+	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
+
+	return request_irq(idma->irq, iomd_dma_handle,
+			   0, idma->dma.device_id, idma);
+}
+
+static void iomd_free_dma(unsigned int chan, dma_t *dma)
+{
+	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
+
+	free_irq(idma->irq, idma);
+}
+
+static void iomd_enable_dma(unsigned int chan, dma_t *dma)
+{
+	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
+	unsigned long dma_base = idma->base;
+	unsigned int ctrl = TRANSFER_SIZE | DMA_CR_E;
+
+	if (idma->dma.invalid) {
+		idma->dma.invalid = 0;
+
+		/*
+		 * Cope with ISA-style drivers which expect cache
+		 * coherence.
+		 */
+		if (!idma->dma.sg) {
+			idma->dma.sg = &idma->dma.buf;
+			idma->dma.sgcount = 1;
+			idma->dma.buf.length = idma->dma.count;
+			idma->dma.buf.dma_address = dma_map_single(NULL,
+				idma->dma.addr, idma->dma.count,
+				idma->dma.dma_mode == DMA_MODE_READ ?
+				DMA_FROM_DEVICE : DMA_TO_DEVICE);
+		}
+
+		iomd_writeb(DMA_CR_C, dma_base + CR);
+		idma->state = DMA_ST_AB;
+	}
+
+	if (idma->dma.dma_mode == DMA_MODE_READ)
+		ctrl |= DMA_CR_D;
+
+	iomd_writeb(ctrl, dma_base + CR);
+	enable_irq(idma->irq);
+}
+
+static void iomd_disable_dma(unsigned int chan, dma_t *dma)
+{
+	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);
+	unsigned long dma_base = idma->base;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	if (idma->state != ~DMA_ST_AB)
+		disable_irq(idma->irq);
+	iomd_writeb(0, dma_base + CR);
+	local_irq_restore(flags);
+}
+
+static int iomd_set_dma_speed(unsigned int chan, dma_t *dma, int cycle)
+{
+	int tcr, speed;
+
+	if (cycle < 188)
+		speed = 3;
+	else if (cycle <= 250)
+		speed = 2;
+	else if (cycle < 438)
+		speed = 1;
+	else
+		speed = 0;
+
+	tcr = iomd_readb(IOMD_DMATCR);
+	speed &= 3;
+
+	switch (chan) {
+	case DMA_0:
+		tcr = (tcr & ~0x03) | speed;
+		break;
+
+	case DMA_1:
+		tcr = (tcr & ~0x0c) | (speed << 2);
+		break;
+
+	case DMA_2:
+		tcr = (tcr & ~0x30) | (speed << 4);
+		break;
+
+	case DMA_3:
+		tcr = (tcr & ~0xc0) | (speed << 6);
+		break;
+
+	default:
+		break;
+	}
+
+	iomd_writeb(tcr, IOMD_DMATCR);
+
+	return speed;
+}
+
+static struct dma_ops iomd_dma_ops = {
+	.type		= "IOMD",
+	.request	= iomd_request_dma,
+	.free		= iomd_free_dma,
+	.enable		= iomd_enable_dma,
+	.disable	= iomd_disable_dma,
+	.setspeed	= iomd_set_dma_speed,
+};
+
+static struct fiq_handler fh = {
+	.name	= "floppydma"
+};
+
+struct floppy_dma {
+	struct dma_struct	dma;
+	unsigned int		fiq;
+};
+
+static void floppy_enable_dma(unsigned int chan, dma_t *dma)
+{
+	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
+	void *fiqhandler_start;
+	unsigned int fiqhandler_length;
+	struct pt_regs regs;
+
+	if (fdma->dma.sg)
+		BUG();
+
+	if (fdma->dma.dma_mode == DMA_MODE_READ) {
+		extern unsigned char floppy_fiqin_start, floppy_fiqin_end;
+		fiqhandler_start = &floppy_fiqin_start;
+		fiqhandler_length = &floppy_fiqin_end - &floppy_fiqin_start;
+	} else {
+		extern unsigned char floppy_fiqout_start, floppy_fiqout_end;
+		fiqhandler_start = &floppy_fiqout_start;
+		fiqhandler_length = &floppy_fiqout_end - &floppy_fiqout_start;
+	}
+
+	regs.ARM_r9  = fdma->dma.count;
+	regs.ARM_r10 = (unsigned long)fdma->dma.addr;
+	regs.ARM_fp  = (unsigned long)FLOPPYDMA_BASE;
+
+	if (claim_fiq(&fh)) {
+		printk("floppydma: couldn't claim FIQ.\n");
+		return;
+	}
+
+	set_fiq_handler(fiqhandler_start, fiqhandler_length);
+	set_fiq_regs(&regs);
+	enable_fiq(fdma->fiq);
+}
+
+static void floppy_disable_dma(unsigned int chan, dma_t *dma)
+{
+	struct floppy_dma *fdma = container_of(dma, struct floppy_dma, dma);
+	disable_fiq(fdma->fiq);
+	release_fiq(&fh);
+}
+
+static int floppy_get_residue(unsigned int chan, dma_t *dma)
+{
+	struct pt_regs regs;
+	get_fiq_regs(&regs);
+	return regs.ARM_r9;
+}
+
+static struct dma_ops floppy_dma_ops = {
+	.type		= "FIQDMA",
+	.enable		= floppy_enable_dma,
+	.disable	= floppy_disable_dma,
+	.residue	= floppy_get_residue,
+};
+
+/*
+ * This is virtual DMA - we don't need anything here.
+ */
+static void sound_enable_disable_dma(unsigned int chan, dma_t *dma)
+{
+}
+
+static struct dma_ops sound_dma_ops = {
+	.type		= "VIRTUAL",
+	.enable		= sound_enable_disable_dma,
+	.disable	= sound_enable_disable_dma,
+};
+
+static struct iomd_dma iomd_dma[6];
+
+static struct floppy_dma floppy_dma = {
+	.dma		= {
+		.d_ops	= &floppy_dma_ops,
+	},
+	.fiq		= FIQ_FLOPPYDATA,
+};
+
+static dma_t sound_dma = {
+	.d_ops		= &sound_dma_ops,
+};
+
+static int __init rpc_dma_init(void)
+{
+	unsigned int i;
+	int ret;
+
+	iomd_writeb(0, IOMD_IO0CR);
+	iomd_writeb(0, IOMD_IO1CR);
+	iomd_writeb(0, IOMD_IO2CR);
+	iomd_writeb(0, IOMD_IO3CR);
+
+	iomd_writeb(0xa0, IOMD_DMATCR);
+
+	/*
+	 * Setup DMA channels 2,3 to be for podules
+	 * and channels 0,1 for internal devices
+	 */
+	iomd_writeb(DMA_EXT_IO3|DMA_EXT_IO2, IOMD_DMAEXT);
+
+	iomd_dma[DMA_0].base	= IOMD_IO0CURA;
+	iomd_dma[DMA_0].irq	= IRQ_DMA0;
+	iomd_dma[DMA_1].base	= IOMD_IO1CURA;
+	iomd_dma[DMA_1].irq	= IRQ_DMA1;
+	iomd_dma[DMA_2].base	= IOMD_IO2CURA;
+	iomd_dma[DMA_2].irq	= IRQ_DMA2;
+	iomd_dma[DMA_3].base	= IOMD_IO3CURA;
+	iomd_dma[DMA_3].irq	= IRQ_DMA3;
+	iomd_dma[DMA_S0].base	= IOMD_SD0CURA;
+	iomd_dma[DMA_S0].irq	= IRQ_DMAS0;
+	iomd_dma[DMA_S1].base	= IOMD_SD1CURA;
+	iomd_dma[DMA_S1].irq	= IRQ_DMAS1;
+
+	for (i = DMA_0; i <= DMA_S1; i++) {
+		iomd_dma[i].dma.d_ops = &iomd_dma_ops;
+
+		ret = isa_dma_add(i, &iomd_dma[i].dma);
+		if (ret)
+			printk("IOMDDMA%u: unable to register: %d\n", i, ret);
+	}
+
+	ret = isa_dma_add(DMA_VIRTUAL_FLOPPY, &floppy_dma.dma);
+	if (ret)
+		printk("IOMDFLOPPY: unable to register: %d\n", ret);
+	ret = isa_dma_add(DMA_VIRTUAL_SOUND, &sound_dma);
+	if (ret)
+		printk("IOMDSOUND: unable to register: %d\n", ret);
+	return 0;
+}
+core_initcall(rpc_dma_init);

arch/arm/mach-rpc/ecard.h

@@ -0,0 +1,69 @@
+/*
+ *  ecard.h
+ *
+ *  Copyright 2007 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* Definitions internal to ecard.c - for it's use only!!
+ *
+ * External expansion card header as read from the card
+ */
+struct ex_ecid {
+	unsigned char	r_irq:1;
+	unsigned char	r_zero:1;
+	unsigned char	r_fiq:1;
+	unsigned char	r_id:4;
+	unsigned char	r_a:1;
+
+	unsigned char	r_cd:1;
+	unsigned char	r_is:1;
+	unsigned char	r_w:2;
+	unsigned char	r_r1:4;
+
+	unsigned char	r_r2:8;
+
+	unsigned char	r_prod[2];
+
+	unsigned char	r_manu[2];
+
+	unsigned char	r_country;
+
+	unsigned char	r_fiqmask;
+	unsigned char	r_fiqoff[3];
+
+	unsigned char	r_irqmask;
+	unsigned char	r_irqoff[3];
+};
+
+/*
+ * Chunk directory entry as read from the card
+ */
+struct ex_chunk_dir {
+	unsigned char r_id;
+	unsigned char r_len[3];
+	unsigned long r_start;
+	union {
+		char string[256];
+		char data[1];
+	} d;
+#define c_id(x)		((x)->r_id)
+#define c_len(x)	((x)->r_len[0]|((x)->r_len[1]<<8)|((x)->r_len[2]<<16))
+#define c_start(x)	((x)->r_start)
+};
+
+typedef enum ecard_type {		/* Cards address space		*/
+	ECARD_IOC,
+	ECARD_MEMC,
+	ECARD_EASI
+} card_type_t;
+
+typedef enum {				/* Speed for ECARD_IOC space	*/
+	ECARD_SLOW	 = 0,
+	ECARD_MEDIUM	 = 1,
+	ECARD_FAST	 = 2,
+	ECARD_SYNC	 = 3
+} card_speed_t;

arch/arm/mach-rpc/fiq.S

@@ -0,0 +1,16 @@
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+#include <mach/entry-macro.S>
+
+	.text
+
+	.global	rpc_default_fiq_end
+ENTRY(rpc_default_fiq_start)
+	mov	r12, #ioc_base_high
+	.if	ioc_base_low
+	orr	r12, r12, #ioc_base_low
+	.endif
+	strb	r12, [r12, #0x38]	@ Disable FIQ register
+	subs	pc, lr, #4
+rpc_default_fiq_end:

arch/arm/mach-rpc/include/mach/acornfb.h

@@ -0,0 +1,140 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/acornfb.h
+ *
+ *  Copyright (C) 1999 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  AcornFB architecture specific code
+ */
+
+#define acornfb_bandwidth(var) ((var)->pixclock * 8 / (var)->bits_per_pixel)
+
+static inline int
+acornfb_valid_pixrate(struct fb_var_screeninfo *var)
+{
+	u_long limit;
+
+	if (!var->pixclock)
+		return 0;
+
+	/*
+	 * Limits below are taken from RISC OS bandwidthlimit file
+	 */
+	if (current_par.using_vram) {
+		if (current_par.vram_half_sam == 2048)
+			limit = 6578;
+		else
+			limit = 13157;
+	} else {
+		limit = 26315;
+	}
+
+	return acornfb_bandwidth(var) >= limit;
+}
+
+/*
+ * Try to find the best PLL parameters for the pixel clock.
+ * This algorithm seems to give best predictable results,
+ * and produces the same values as detailed in the VIDC20
+ * data sheet.
+ */
+static inline u_int
+acornfb_vidc20_find_pll(u_int pixclk)
+{
+	u_int r, best_r = 2, best_v = 2;
+	int best_d = 0x7fffffff;
+
+	for (r = 2; r <= 32; r++) {
+		u_int rr, v, p;
+		int d;
+
+		rr = 41667 * r;
+
+		v = (rr + pixclk / 2) / pixclk;
+
+		if (v > 32 || v < 2)
+			continue;
+
+		p = (rr + v / 2) / v;
+
+		d = pixclk - p;
+
+		if (d < 0)
+			d = -d;
+
+		if (d < best_d) {
+			best_d = d;
+			best_v = v - 1;
+			best_r = r - 1;
+		}
+
+		if (d == 0)
+			break;
+	}
+
+	return best_v << 8 | best_r;
+}
+
+static inline void
+acornfb_vidc20_find_rates(struct vidc_timing *vidc,
+			  struct fb_var_screeninfo *var)
+{
+	u_int div;
+
+	/* Select pixel-clock divisor to keep PLL in range */
+	div = var->pixclock / 9090; /*9921*/
+
+	/* Limit divisor */
+	if (div == 0)
+		div = 1;
+	if (div > 8)
+		div = 8;
+
+	/* Encode divisor to VIDC20 setting */
+	switch (div) {
+	case 1:	vidc->control |= VIDC20_CTRL_PIX_CK;  break;
+	case 2:	vidc->control |= VIDC20_CTRL_PIX_CK2; break;
+	case 3:	vidc->control |= VIDC20_CTRL_PIX_CK3; break;
+	case 4:	vidc->control |= VIDC20_CTRL_PIX_CK4; break;
+	case 5:	vidc->control |= VIDC20_CTRL_PIX_CK5; break;
+	case 6:	vidc->control |= VIDC20_CTRL_PIX_CK6; break;
+	case 7:	vidc->control |= VIDC20_CTRL_PIX_CK7; break;
+	case 8: vidc->control |= VIDC20_CTRL_PIX_CK8; break;
+	}
+
+	/*
+	 * With VRAM, the FIFO can be set to the highest possible setting
+	 * because there are no latency considerations for other memory
+	 * accesses. However, in 64 bit bus mode the FIFO preload value
+	 * must not be set to VIDC20_CTRL_FIFO_28 because this will let
+	 * the FIFO overflow. See VIDC20 manual page 33 (6.0 Setting the
+	 * FIFO preload value).
+	 */
+	if (current_par.using_vram) {
+		if (current_par.vram_half_sam == 2048)
+			vidc->control |= VIDC20_CTRL_FIFO_24;
+		else
+			vidc->control |= VIDC20_CTRL_FIFO_28;
+	} else {
+		unsigned long bandwidth = acornfb_bandwidth(var);
+
+		/* Encode bandwidth as VIDC20 setting */
+		if (bandwidth > 33334)		/* < 30.0MB/s */
+			vidc->control |= VIDC20_CTRL_FIFO_16;
+		else if (bandwidth > 26666)	/* < 37.5MB/s */
+			vidc->control |= VIDC20_CTRL_FIFO_20;
+		else if (bandwidth > 22222)	/* < 45.0MB/s */
+			vidc->control |= VIDC20_CTRL_FIFO_24;
+		else				/* > 45.0MB/s */
+			vidc->control |= VIDC20_CTRL_FIFO_28;
+	}
+
+	/* Find the PLL values */
+	vidc->pll_ctl = acornfb_vidc20_find_pll(var->pixclock / div);
+}
+
+#define acornfb_default_control()	(VIDC20_CTRL_PIX_VCLK)
+#define acornfb_default_econtrol()	(VIDC20_ECTL_DAC | VIDC20_ECTL_REG(3))

arch/arm/mach-rpc/include/mach/entry-macro.S

@@ -0,0 +1,12 @@
+#include <mach/hardware.h>
+#include <asm/hardware/entry-macro-iomd.S>
+
+	.equ	ioc_base_high, IOC_BASE & 0xff000000
+	.equ	ioc_base_low, IOC_BASE & 0x00ff0000
+
+	.macro  get_irqnr_preamble, base, tmp
+	mov	\base, #ioc_base_high		@ point at IOC
+	.if	ioc_base_low
+	orr	\base, \base, #ioc_base_low
+	.endif
+	.endm

arch/arm/mach-rpc/include/mach/hardware.h

@@ -0,0 +1,76 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/hardware.h
+ *
+ *  Copyright (C) 1996-1999 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  This file contains the hardware definitions of the RiscPC series machines.
+ */
+#ifndef __ASM_ARCH_HARDWARE_H
+#define __ASM_ARCH_HARDWARE_H
+
+#include <mach/memory.h>
+
+/*
+ * What hardware must be present
+ */
+#define HAS_IOMD
+#define HAS_VIDC20
+
+/* Hardware addresses of major areas.
+ *  *_START is the physical address
+ *  *_SIZE  is the size of the region
+ *  *_BASE  is the virtual address
+ */
+#define RAM_SIZE		0x10000000
+#define RAM_START		0x10000000
+
+#define EASI_SIZE		0x08000000	/* EASI I/O */
+#define EASI_START		0x08000000
+#define EASI_BASE		IOMEM(0xe5000000)
+
+#define IO_START		0x03000000	/* I/O */
+#define IO_SIZE			0x01000000
+#define IO_BASE			IOMEM(0xe0000000)
+
+#define SCREEN_START		0x02000000	/* VRAM */
+#define SCREEN_END		0xdfc00000
+#define SCREEN_BASE		0xdf800000
+
+#define UNCACHEABLE_ADDR	0xdf010000
+
+/*
+ * IO Addresses
+ */
+#define ECARD_EASI_BASE		(EASI_BASE)
+#define VIDC_BASE		(IO_BASE + 0x00400000)
+#define EXPMASK_BASE		(IO_BASE + 0x00360000)
+#define ECARD_IOC4_BASE		(IO_BASE + 0x00270000)
+#define ECARD_IOC_BASE		(IO_BASE + 0x00240000)
+#define IOMD_BASE		(IO_BASE + 0x00200000)
+#define IOC_BASE		(IO_BASE + 0x00200000)
+#define ECARD_MEMC8_BASE	(IO_BASE + 0x0002b000)
+#define FLOPPYDMA_BASE		(IO_BASE + 0x0002a000)
+#define PCIO_BASE		(IO_BASE + 0x00010000)
+#define ECARD_MEMC_BASE		(IO_BASE + 0x00000000)
+
+#define vidc_writel(val)	__raw_writel(val, VIDC_BASE)
+
+#define NETSLOT_BASE		0x0302b000
+#define NETSLOT_SIZE		0x00001000
+
+#define PODSLOT_IOC0_BASE	0x03240000
+#define PODSLOT_IOC4_BASE	0x03270000
+#define PODSLOT_IOC_SIZE	(1 << 14)
+#define PODSLOT_MEMC_BASE	0x03000000
+#define PODSLOT_MEMC_SIZE	(1 << 14)
+#define PODSLOT_EASI_BASE	0x08000000
+#define PODSLOT_EASI_SIZE	(1 << 24)
+
+#define	EXPMASK_STATUS		(EXPMASK_BASE + 0x00)
+#define EXPMASK_ENABLE		(EXPMASK_BASE + 0x04)
+
+#endif

arch/arm/mach-rpc/include/mach/io.h

@@ -0,0 +1,31 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/io.h
+ *
+ *  Copyright (C) 1997 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Modifications:
+ *  06-Dec-1997	RMK	Created.
+ */
+#ifndef __ASM_ARM_ARCH_IO_H
+#define __ASM_ARM_ARCH_IO_H
+
+#include <mach/hardware.h>
+
+#define IO_SPACE_LIMIT 0xffff
+
+/*
+ * We need PC style IO addressing for:
+ *  - floppy (at 0x3f2,0x3f4,0x3f5,0x3f7)
+ *  - parport (at 0x278-0x27a, 0x27b-0x27f, 0x778-0x77a)
+ *  - 8250 serial (only for compile)
+ *
+ * These peripherals are found in an area of MMIO which looks very much
+ * like an ISA bus, but with registers at the low byte of each word.
+ */
+#define __io(a)		(PCIO_BASE + ((a) << 2))
+
+#endif

arch/arm/mach-rpc/include/mach/irqs.h

@@ -0,0 +1,45 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/irqs.h
+ *
+ *  Copyright (C) 1996 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define IRQ_PRINTER		0
+#define IRQ_BATLOW		1
+#define IRQ_FLOPPYINDEX		2
+#define IRQ_VSYNCPULSE		3
+#define IRQ_POWERON		4
+#define IRQ_TIMER0		5
+#define IRQ_TIMER1		6
+#define IRQ_IMMEDIATE		7
+#define IRQ_EXPCARDFIQ		8
+#define IRQ_HARDDISK		9
+#define IRQ_SERIALPORT		10
+#define IRQ_FLOPPYDISK		12
+#define IRQ_EXPANSIONCARD	13
+#define IRQ_KEYBOARDTX		14
+#define IRQ_KEYBOARDRX		15
+
+#define IRQ_DMA0		16
+#define IRQ_DMA1		17
+#define IRQ_DMA2		18
+#define IRQ_DMA3		19
+#define IRQ_DMAS0		20
+#define IRQ_DMAS1		21
+
+#define FIQ_FLOPPYDATA		0
+#define FIQ_ECONET		2
+#define FIQ_SERIALPORT		4
+#define FIQ_EXPANSIONCARD	6
+#define FIQ_FORCE		7
+
+/*
+ * This is the offset of the FIQ "IRQ" numbers
+ */
+#define FIQ_START		64
+
+#define NR_IRQS			128

arch/arm/mach-rpc/include/mach/isa-dma.h

@@ -0,0 +1,29 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/isa-dma.h
+ *
+ *  Copyright (C) 1997 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_ARCH_DMA_H
+#define __ASM_ARCH_DMA_H
+
+#define MAX_DMA_CHANNELS	8
+
+#define DMA_0			0
+#define DMA_1			1
+#define DMA_2			2
+#define DMA_3			3
+#define DMA_S0			4
+#define DMA_S1			5
+#define DMA_VIRTUAL_FLOPPY	6
+#define DMA_VIRTUAL_SOUND	7
+
+#define DMA_FLOPPY		DMA_VIRTUAL_FLOPPY
+
+#define IOMD_DMA_BOUNDARY	(PAGE_SIZE - 1)
+
+#endif /* _ASM_ARCH_DMA_H */
+

arch/arm/mach-rpc/include/mach/memory.h

@@ -0,0 +1,35 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/memory.h
+ *
+ *  Copyright (C) 1996,1997,1998 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Changelog:
+ *   20-Oct-1996 RMK	Created
+ *   31-Dec-1997 RMK	Fixed definitions to reduce warnings
+ *   11-Jan-1998 RMK	Uninlined to reduce hits on cache
+ *   08-Feb-1998 RMK	Added __virt_to_bus and __bus_to_virt
+ *   21-Mar-1999 RMK	Renamed to memory.h
+ *		 RMK	Added TASK_SIZE and PAGE_OFFSET
+ */
+#ifndef __ASM_ARCH_MEMORY_H
+#define __ASM_ARCH_MEMORY_H
+
+/*
+ * Cache flushing area - ROM
+ */
+#define FLUSH_BASE_PHYS		0x00000000
+#define FLUSH_BASE		0xdf000000
+
+/*
+ * Sparsemem support.  Each section is a maximum of 64MB.  The sections
+ * are offset by 128MB and can cover 128MB, so that gives us a maximum
+ * of 29 physmem bits.
+ */
+#define MAX_PHYSMEM_BITS	29
+#define SECTION_SIZE_BITS	26
+
+#endif

arch/arm/mach-rpc/include/mach/uncompress.h

@@ -0,0 +1,191 @@
+/*
+ *  arch/arm/mach-rpc/include/mach/uncompress.h
+ *
+ *  Copyright (C) 1996 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define VIDMEM ((char *)SCREEN_START)
+ 
+#include <linux/io.h>
+#include <mach/hardware.h>
+#include <asm/setup.h>
+#include <asm/page.h>
+
+int video_size_row;
+unsigned char bytes_per_char_h;
+extern unsigned long con_charconvtable[256];
+
+struct param_struct {
+	unsigned long page_size;
+	unsigned long nr_pages;
+	unsigned long ramdisk_size;
+	unsigned long mountrootrdonly;
+	unsigned long rootdev;
+	unsigned long video_num_cols;
+	unsigned long video_num_rows;
+	unsigned long video_x;
+	unsigned long video_y;
+	unsigned long memc_control_reg;
+	unsigned char sounddefault;
+	unsigned char adfsdrives;
+	unsigned char bytes_per_char_h;
+	unsigned char bytes_per_char_v;
+	unsigned long unused[256/4-11];
+};
+
+static const unsigned long palette_4[16] = {
+	0x00000000,
+	0x000000cc,
+	0x0000cc00,             /* Green   */
+	0x0000cccc,             /* Yellow  */
+	0x00cc0000,             /* Blue    */
+	0x00cc00cc,             /* Magenta */
+	0x00cccc00,             /* Cyan    */
+	0x00cccccc,             /* White   */
+	0x00000000,
+	0x000000ff,
+	0x0000ff00,
+	0x0000ffff,
+	0x00ff0000,
+	0x00ff00ff,
+	0x00ffff00,
+	0x00ffffff
+};
+
+#define palette_setpixel(p)	*(unsigned long *)(IO_START+0x00400000) = 0x10000000|((p) & 255)
+#define palette_write(v)	*(unsigned long *)(IO_START+0x00400000) = 0x00000000|((v) & 0x00ffffff)
+
+/*
+ * params_phys is a linker defined symbol - see
+ * arch/arm/boot/compressed/Makefile
+ */
+extern __attribute__((pure)) struct param_struct *params(void);
+#define params (params())
+
+#ifndef STANDALONE_DEBUG 
+unsigned long video_num_cols;
+unsigned long video_num_rows;
+unsigned long video_x;
+unsigned long video_y;
+unsigned char bytes_per_char_v;
+int white;
+
+/*
+ * This does not append a newline
+ */
+static void putc(int c)
+{
+	extern void ll_write_char(char *, char c, char white);
+	int x,y;
+	char *ptr;
+
+	x = video_x;
+	y = video_y;
+
+	if (c == '\n') {
+		if (++y >= video_num_rows)
+			y--;
+	} else if (c == '\r') {
+		x = 0;
+	} else {
+		ptr = VIDMEM + ((y*video_num_cols*bytes_per_char_v+x)*bytes_per_char_h);
+		ll_write_char(ptr, c, white);
+		if (++x >= video_num_cols) {
+			x = 0;
+			if ( ++y >= video_num_rows ) {
+				y--;
+			}
+		}
+	}
+
+	video_x = x;
+	video_y = y;
+}
+
+static inline void flush(void)
+{
+}
+
+/*
+ * Setup for decompression
+ */
+static void arch_decomp_setup(void)
+{
+	int i;
+	struct tag *t = (struct tag *)params;
+	unsigned int nr_pages = 0, page_size = PAGE_SIZE;
+
+	if (t->hdr.tag == ATAG_CORE)
+	{
+		for (; t->hdr.size; t = tag_next(t))
+		{
+			if (t->hdr.tag == ATAG_VIDEOTEXT)
+			{
+				video_num_rows = t->u.videotext.video_lines;
+				video_num_cols = t->u.videotext.video_cols;
+				bytes_per_char_h = t->u.videotext.video_points;
+				bytes_per_char_v = t->u.videotext.video_points;
+				video_x = t->u.videotext.x;
+				video_y = t->u.videotext.y;
+			}
+
+			if (t->hdr.tag == ATAG_MEM)
+			{
+				page_size = PAGE_SIZE;
+				nr_pages += (t->u.mem.size / PAGE_SIZE);
+			}
+		}
+	}
+	else
+	{
+		nr_pages = params->nr_pages;
+		page_size = params->page_size;
+		video_num_rows = params->video_num_rows;
+		video_num_cols = params->video_num_cols;
+		video_x = params->video_x;
+		video_y = params->video_y;
+		bytes_per_char_h = params->bytes_per_char_h;
+		bytes_per_char_v = params->bytes_per_char_v;
+	}
+
+	video_size_row = video_num_cols * bytes_per_char_h;
+	
+	if (bytes_per_char_h == 4)
+		for (i = 0; i < 256; i++)
+			con_charconvtable[i] =
+				(i & 128 ? 1 << 0  : 0) |
+				(i & 64  ? 1 << 4  : 0) |
+				(i & 32  ? 1 << 8  : 0) |
+				(i & 16  ? 1 << 12 : 0) |
+				(i & 8   ? 1 << 16 : 0) |
+				(i & 4   ? 1 << 20 : 0) |
+				(i & 2   ? 1 << 24 : 0) |
+				(i & 1   ? 1 << 28 : 0);
+	else
+		for (i = 0; i < 16; i++)
+			con_charconvtable[i] =
+				(i & 8   ? 1 << 0  : 0) |
+				(i & 4   ? 1 << 8  : 0) |
+				(i & 2   ? 1 << 16 : 0) |
+				(i & 1   ? 1 << 24 : 0);
+
+
+	palette_setpixel(0);
+	if (bytes_per_char_h == 1) {
+		palette_write (0);
+		palette_write (0x00ffffff);
+		for (i = 2; i < 256; i++)
+			palette_write (0);
+		white = 1;
+	} else {
+		for (i = 0; i < 256; i++)
+			palette_write (i < 16 ? palette_4[i] : 0);
+		white = 7;
+	}
+
+	if (nr_pages * page_size < 4096*1024) error("<4M of mem\n");
+}
+#endif

arch/arm/mach-rpc/irq.c

@@ -0,0 +1,168 @@
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/io.h>
+
+#include <asm/mach/irq.h>
+#include <asm/hardware/iomd.h>
+#include <asm/irq.h>
+#include <asm/fiq.h>
+
+static void iomd_ack_irq_a(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << d->irq;
+	val = iomd_readb(IOMD_IRQMASKA);
+	iomd_writeb(val & ~mask, IOMD_IRQMASKA);
+	iomd_writeb(mask, IOMD_IRQCLRA);
+}
+
+static void iomd_mask_irq_a(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << d->irq;
+	val = iomd_readb(IOMD_IRQMASKA);
+	iomd_writeb(val & ~mask, IOMD_IRQMASKA);
+}
+
+static void iomd_unmask_irq_a(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << d->irq;
+	val = iomd_readb(IOMD_IRQMASKA);
+	iomd_writeb(val | mask, IOMD_IRQMASKA);
+}
+
+static struct irq_chip iomd_a_chip = {
+	.irq_ack	= iomd_ack_irq_a,
+	.irq_mask	= iomd_mask_irq_a,
+	.irq_unmask	= iomd_unmask_irq_a,
+};
+
+static void iomd_mask_irq_b(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_IRQMASKB);
+	iomd_writeb(val & ~mask, IOMD_IRQMASKB);
+}
+
+static void iomd_unmask_irq_b(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_IRQMASKB);
+	iomd_writeb(val | mask, IOMD_IRQMASKB);
+}
+
+static struct irq_chip iomd_b_chip = {
+	.irq_ack	= iomd_mask_irq_b,
+	.irq_mask	= iomd_mask_irq_b,
+	.irq_unmask	= iomd_unmask_irq_b,
+};
+
+static void iomd_mask_irq_dma(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_DMAMASK);
+	iomd_writeb(val & ~mask, IOMD_DMAMASK);
+}
+
+static void iomd_unmask_irq_dma(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_DMAMASK);
+	iomd_writeb(val | mask, IOMD_DMAMASK);
+}
+
+static struct irq_chip iomd_dma_chip = {
+	.irq_ack	= iomd_mask_irq_dma,
+	.irq_mask	= iomd_mask_irq_dma,
+	.irq_unmask	= iomd_unmask_irq_dma,
+};
+
+static void iomd_mask_irq_fiq(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_FIQMASK);
+	iomd_writeb(val & ~mask, IOMD_FIQMASK);
+}
+
+static void iomd_unmask_irq_fiq(struct irq_data *d)
+{
+	unsigned int val, mask;
+
+	mask = 1 << (d->irq & 7);
+	val = iomd_readb(IOMD_FIQMASK);
+	iomd_writeb(val | mask, IOMD_FIQMASK);
+}
+
+static struct irq_chip iomd_fiq_chip = {
+	.irq_ack	= iomd_mask_irq_fiq,
+	.irq_mask	= iomd_mask_irq_fiq,
+	.irq_unmask	= iomd_unmask_irq_fiq,
+};
+
+extern unsigned char rpc_default_fiq_start, rpc_default_fiq_end;
+
+void __init rpc_init_irq(void)
+{
+	unsigned int irq, flags;
+
+	iomd_writeb(0, IOMD_IRQMASKA);
+	iomd_writeb(0, IOMD_IRQMASKB);
+	iomd_writeb(0, IOMD_FIQMASK);
+	iomd_writeb(0, IOMD_DMAMASK);
+
+	set_fiq_handler(&rpc_default_fiq_start,
+		&rpc_default_fiq_end - &rpc_default_fiq_start);
+
+	for (irq = 0; irq < NR_IRQS; irq++) {
+		flags = IRQF_VALID;
+
+		if (irq <= 6 || (irq >= 9 && irq <= 15))
+			flags |= IRQF_PROBE;
+
+		if (irq == 21 || (irq >= 16 && irq <= 19) ||
+		    irq == IRQ_KEYBOARDTX)
+			flags |= IRQF_NOAUTOEN;
+
+		switch (irq) {
+		case 0 ... 7:
+			irq_set_chip_and_handler(irq, &iomd_a_chip,
+						 handle_level_irq);
+			set_irq_flags(irq, flags);
+			break;
+
+		case 8 ... 15:
+			irq_set_chip_and_handler(irq, &iomd_b_chip,
+						 handle_level_irq);
+			set_irq_flags(irq, flags);
+			break;
+
+		case 16 ... 21:
+			irq_set_chip_and_handler(irq, &iomd_dma_chip,
+						 handle_level_irq);
+			set_irq_flags(irq, flags);
+			break;
+
+		case 64 ... 71:
+			irq_set_chip(irq, &iomd_fiq_chip);
+			set_irq_flags(irq, IRQF_VALID);
+			break;
+		}
+	}
+
+	init_FIQ(FIQ_START);
+}
+

arch/arm/mach-rpc/riscpc.c

@@ -0,0 +1,226 @@
+/*
+ *  linux/arch/arm/mach-rpc/riscpc.c
+ *
+ *  Copyright (C) 1998-2001 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Architecture specific fixups.
+ */
+#include <linux/kernel.h>
+#include <linux/tty.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/device.h>
+#include <linux/serial_8250.h>
+#include <linux/ata_platform.h>
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/reboot.h>
+
+#include <asm/elf.h>
+#include <asm/mach-types.h>
+#include <mach/hardware.h>
+#include <asm/hardware/iomd.h>
+#include <asm/page.h>
+#include <asm/domain.h>
+#include <asm/setup.h>
+#include <asm/system_misc.h>
+
+#include <asm/mach/map.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/time.h>
+
+extern void rpc_init_irq(void);
+
+unsigned int vram_size;
+unsigned int memc_ctrl_reg;
+unsigned int number_mfm_drives;
+
+static int __init parse_tag_acorn(const struct tag *tag)
+{
+	memc_ctrl_reg = tag->u.acorn.memc_control_reg;
+	number_mfm_drives = tag->u.acorn.adfsdrives;
+
+	switch (tag->u.acorn.vram_pages) {
+	case 512:
+		vram_size += PAGE_SIZE * 256;
+	case 256:
+		vram_size += PAGE_SIZE * 256;
+	default:
+		break;
+	}
+#if 0
+	if (vram_size) {
+		desc->video_start = 0x02000000;
+		desc->video_end   = 0x02000000 + vram_size;
+	}
+#endif
+	return 0;
+}
+
+__tagtable(ATAG_ACORN, parse_tag_acorn);
+
+static struct map_desc rpc_io_desc[] __initdata = {
+ 	{	/* VRAM		*/
+		.virtual	=  SCREEN_BASE,
+		.pfn		= __phys_to_pfn(SCREEN_START),
+		.length		= 	2*1048576,
+		.type		= MT_DEVICE
+	}, {	/* IO space	*/
+		.virtual	=  (u32)IO_BASE,
+		.pfn		= __phys_to_pfn(IO_START),
+		.length		= 	IO_SIZE	 ,
+		.type		= MT_DEVICE
+	}, {	/* EASI space	*/
+		.virtual	= (unsigned long)EASI_BASE,
+		.pfn		= __phys_to_pfn(EASI_START),
+		.length		= EASI_SIZE,
+		.type		= MT_DEVICE
+	}
+};
+
+static void __init rpc_map_io(void)
+{
+	iotable_init(rpc_io_desc, ARRAY_SIZE(rpc_io_desc));
+
+	/*
+	 * Turn off floppy.
+	 */
+	writeb(0xc, PCIO_BASE + (0x3f2 << 2));
+
+	/*
+	 * RiscPC can't handle half-word loads and stores
+	 */
+	elf_hwcap &= ~HWCAP_HALF;
+}
+
+static struct resource acornfb_resources[] = {
+	/* VIDC */
+	DEFINE_RES_MEM(0x03400000, 0x00200000),
+	DEFINE_RES_IRQ(IRQ_VSYNCPULSE),
+};
+
+static struct platform_device acornfb_device = {
+	.name			= "acornfb",
+	.id			= -1,
+	.dev			= {
+		.coherent_dma_mask = 0xffffffff,
+	},
+	.num_resources		= ARRAY_SIZE(acornfb_resources),
+	.resource		= acornfb_resources,
+};
+
+static struct resource iomd_resources[] = {
+	DEFINE_RES_MEM(0x03200000, 0x10000),
+};
+
+static struct platform_device iomd_device = {
+	.name			= "iomd",
+	.id			= -1,
+	.num_resources		= ARRAY_SIZE(iomd_resources),
+	.resource		= iomd_resources,
+};
+
+static struct resource iomd_kart_resources[] = {
+	DEFINE_RES_IRQ(IRQ_KEYBOARDRX),
+	DEFINE_RES_IRQ(IRQ_KEYBOARDTX),
+};
+
+static struct platform_device kbd_device = {
+	.name			= "kart",
+	.id			= -1,
+	.dev			= {
+		.parent 	= &iomd_device.dev,
+	},
+	.num_resources		= ARRAY_SIZE(iomd_kart_resources),
+	.resource		= iomd_kart_resources,
+};
+
+static struct plat_serial8250_port serial_platform_data[] = {
+	{
+		.mapbase	= 0x03010fe0,
+		.irq		= IRQ_SERIALPORT,
+		.uartclk	= 1843200,
+		.regshift	= 2,
+		.iotype		= UPIO_MEM,
+		.flags		= UPF_BOOT_AUTOCONF | UPF_IOREMAP | UPF_SKIP_TEST,
+	},
+	{ },
+};
+
+static struct platform_device serial_device = {
+	.name			= "serial8250",
+	.id			= PLAT8250_DEV_PLATFORM,
+	.dev			= {
+		.platform_data	= serial_platform_data,
+	},
+};
+
+static struct pata_platform_info pata_platform_data = {
+	.ioport_shift		= 2,
+};
+
+static struct resource pata_resources[] = {
+	DEFINE_RES_MEM(0x030107c0, 0x20),
+	DEFINE_RES_MEM(0x03010fd8, 0x04),
+	DEFINE_RES_IRQ(IRQ_HARDDISK),
+};
+
+static struct platform_device pata_device = {
+	.name			= "pata_platform",
+	.id			= -1,
+	.num_resources		= ARRAY_SIZE(pata_resources),
+	.resource		= pata_resources,
+	.dev			= {
+		.platform_data	= &pata_platform_data,
+		.coherent_dma_mask = ~0,	/* grumble */
+	},
+};
+
+static struct platform_device *devs[] __initdata = {
+	&iomd_device,
+	&kbd_device,
+	&serial_device,
+	&acornfb_device,
+	&pata_device,
+};
+
+static struct i2c_board_info i2c_rtc = {
+	I2C_BOARD_INFO("pcf8583", 0x50)
+};
+
+static int __init rpc_init(void)
+{
+	i2c_register_board_info(0, &i2c_rtc, 1);
+	return platform_add_devices(devs, ARRAY_SIZE(devs));
+}
+
+arch_initcall(rpc_init);
+
+static void rpc_restart(enum reboot_mode mode, const char *cmd)
+{
+	iomd_writeb(0, IOMD_ROMCR0);
+
+	/*
+	 * Jump into the ROM
+	 */
+	soft_restart(0);
+}
+
+void ioc_timer_init(void);
+
+MACHINE_START(RISCPC, "Acorn-RiscPC")
+	/* Maintainer: Russell King */
+	.atag_offset	= 0x100,
+	.reserve_lp0	= 1,
+	.reserve_lp1	= 1,
+	.map_io		= rpc_map_io,
+	.init_irq	= rpc_init_irq,
+	.init_time	= ioc_timer_init,
+	.restart	= rpc_restart,
+MACHINE_END

arch/arm/mach-rpc/time.c

@@ -0,0 +1,92 @@
+/*
+ *  linux/arch/arm/common/time-acorn.c
+ *
+ *  Copyright (c) 1996-2000 Russell King.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Changelog:
+ *   24-Sep-1996	RMK	Created
+ *   10-Oct-1996	RMK	Brought up to date with arch-sa110eval
+ *   04-Dec-1997	RMK	Updated for new arch/arm/time.c
+ *   13=Jun-2004	DS	Moved to arch/arm/common b/c shared w/CLPS7500
+ */
+#include <linux/timex.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <asm/hardware/ioc.h>
+
+#include <asm/mach/time.h>
+
+#define RPC_CLOCK_FREQ 2000000
+#define RPC_LATCH DIV_ROUND_CLOSEST(RPC_CLOCK_FREQ, HZ)
+
+static u32 ioc_timer_gettimeoffset(void)
+{
+	unsigned int count1, count2, status;
+	long offset;
+
+	ioc_writeb (0, IOC_T0LATCH);
+	barrier ();
+	count1 = ioc_readb(IOC_T0CNTL) | (ioc_readb(IOC_T0CNTH) << 8);
+	barrier ();
+	status = ioc_readb(IOC_IRQREQA);
+	barrier ();
+	ioc_writeb (0, IOC_T0LATCH);
+	barrier ();
+	count2 = ioc_readb(IOC_T0CNTL) | (ioc_readb(IOC_T0CNTH) << 8);
+
+	offset = count2;
+	if (count2 < count1) {
+		/*
+		 * We have not had an interrupt between reading count1
+		 * and count2.
+		 */
+		if (status & (1 << 5))
+			offset -= RPC_LATCH;
+	} else if (count2 > count1) {
+		/*
+		 * We have just had another interrupt between reading
+		 * count1 and count2.
+		 */
+		offset -= RPC_LATCH;
+	}
+
+	offset = (RPC_LATCH - offset) * (tick_nsec / 1000);
+	return DIV_ROUND_CLOSEST(offset, RPC_LATCH) * 1000;
+}
+
+void __init ioctime_init(void)
+{
+	ioc_writeb(RPC_LATCH & 255, IOC_T0LTCHL);
+	ioc_writeb(RPC_LATCH >> 8, IOC_T0LTCHH);
+	ioc_writeb(0, IOC_T0GO);
+}
+
+static irqreturn_t
+ioc_timer_interrupt(int irq, void *dev_id)
+{
+	timer_tick();
+	return IRQ_HANDLED;
+}
+
+static struct irqaction ioc_timer_irq = {
+	.name		= "timer",
+	.handler	= ioc_timer_interrupt
+};
+
+/*
+ * Set up timer interrupt.
+ */
+void __init ioc_timer_init(void)
+{
+	arch_gettimeoffset = ioc_timer_gettimeoffset;
+	ioctime_init();
+	setup_irq(IRQ_TIMER0, &ioc_timer_irq);
+}