1 /*
2  *  linux/arch/arm/mach-footbridge/common.c
3  *
4  *  Copyright (C) 1998-2000 Russell King, Dave Gilbert.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/module.h>
11 #include <linux/types.h>
12 #include <linux/mm.h>
13 #include <linux/ioport.h>
14 #include <linux/list.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/spinlock.h>
18 
19 #include <asm/pgtable.h>
20 #include <asm/page.h>
21 #include <asm/irq.h>
22 #include <asm/mach-types.h>
23 #include <asm/setup.h>
24 #include <asm/system_misc.h>
25 #include <asm/hardware/dec21285.h>
26 
27 #include <asm/mach/irq.h>
28 #include <asm/mach/map.h>
29 
30 #include "common.h"
31 
32 unsigned int mem_fclk_21285 = 50000000;
33 
34 EXPORT_SYMBOL(mem_fclk_21285);
35 
36 static int __init early_fclk(char *arg)
37 {
38 	mem_fclk_21285 = simple_strtoul(arg, NULL, 0);
39 	return 0;
40 }
41 
42 early_param("mem_fclk_21285", early_fclk);
43 
44 static int __init parse_tag_memclk(const struct tag *tag)
45 {
46 	mem_fclk_21285 = tag->u.memclk.fmemclk;
47 	return 0;
48 }
49 
50 __tagtable(ATAG_MEMCLK, parse_tag_memclk);
51 
52 /*
53  * Footbridge IRQ translation table
54  *  Converts from our IRQ numbers into FootBridge masks
55  */
56 static const int fb_irq_mask[] = {
57 	IRQ_MASK_UART_RX,	/*  0 */
58 	IRQ_MASK_UART_TX,	/*  1 */
59 	IRQ_MASK_TIMER1,	/*  2 */
60 	IRQ_MASK_TIMER2,	/*  3 */
61 	IRQ_MASK_TIMER3,	/*  4 */
62 	IRQ_MASK_IN0,		/*  5 */
63 	IRQ_MASK_IN1,		/*  6 */
64 	IRQ_MASK_IN2,		/*  7 */
65 	IRQ_MASK_IN3,		/*  8 */
66 	IRQ_MASK_DOORBELLHOST,	/*  9 */
67 	IRQ_MASK_DMA1,		/* 10 */
68 	IRQ_MASK_DMA2,		/* 11 */
69 	IRQ_MASK_PCI,		/* 12 */
70 	IRQ_MASK_SDRAMPARITY,	/* 13 */
71 	IRQ_MASK_I2OINPOST,	/* 14 */
72 	IRQ_MASK_PCI_ABORT,	/* 15 */
73 	IRQ_MASK_PCI_SERR,	/* 16 */
74 	IRQ_MASK_DISCARD_TIMER,	/* 17 */
75 	IRQ_MASK_PCI_DPERR,	/* 18 */
76 	IRQ_MASK_PCI_PERR,	/* 19 */
77 };
78 
79 static void fb_mask_irq(struct irq_data *d)
80 {
81 	*CSR_IRQ_DISABLE = fb_irq_mask[_DC21285_INR(d->irq)];
82 }
83 
84 static void fb_unmask_irq(struct irq_data *d)
85 {
86 	*CSR_IRQ_ENABLE = fb_irq_mask[_DC21285_INR(d->irq)];
87 }
88 
89 static struct irq_chip fb_chip = {
90 	.irq_ack	= fb_mask_irq,
91 	.irq_mask	= fb_mask_irq,
92 	.irq_unmask	= fb_unmask_irq,
93 };
94 
95 static void __init __fb_init_irq(void)
96 {
97 	unsigned int irq;
98 
99 	/*
100 	 * setup DC21285 IRQs
101 	 */
102 	*CSR_IRQ_DISABLE = -1;
103 	*CSR_FIQ_DISABLE = -1;
104 
105 	for (irq = _DC21285_IRQ(0); irq < _DC21285_IRQ(20); irq++) {
106 		irq_set_chip_and_handler(irq, &fb_chip, handle_level_irq);
107 		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
108 	}
109 }
110 
111 void __init footbridge_init_irq(void)
112 {
113 	__fb_init_irq();
114 
115 	if (!footbridge_cfn_mode())
116 		return;
117 
118 	if (machine_is_ebsa285())
119 		/* The following is dependent on which slot
120 		 * you plug the Southbridge card into.  We
121 		 * currently assume that you plug it into
122 		 * the right-hand most slot.
123 		 */
124 		isa_init_irq(IRQ_PCI);
125 
126 	if (machine_is_cats())
127 		isa_init_irq(IRQ_IN2);
128 
129 	if (machine_is_netwinder())
130 		isa_init_irq(IRQ_IN3);
131 }
132 
133 /*
134  * Common mapping for all systems.  Note that the outbound write flush is
135  * commented out since there is a "No Fix" problem with it.  Not mapping
136  * it means that we have extra bullet protection on our feet.
137  */
138 static struct map_desc fb_common_io_desc[] __initdata = {
139 	{
140 		.virtual	= ARMCSR_BASE,
141 		.pfn		= __phys_to_pfn(DC21285_ARMCSR_BASE),
142 		.length		= ARMCSR_SIZE,
143 		.type		= MT_DEVICE,
144 	}, {
145 		.virtual	= XBUS_BASE,
146 		.pfn		= __phys_to_pfn(0x40000000),
147 		.length		= XBUS_SIZE,
148 		.type		= MT_DEVICE,
149 	}
150 };
151 
152 /*
153  * The mapping when the footbridge is in host mode.  We don't map any of
154  * this when we are in add-in mode.
155  */
156 static struct map_desc ebsa285_host_io_desc[] __initdata = {
157 #if defined(CONFIG_ARCH_FOOTBRIDGE) && defined(CONFIG_FOOTBRIDGE_HOST)
158 	{
159 		.virtual	= PCIMEM_BASE,
160 		.pfn		= __phys_to_pfn(DC21285_PCI_MEM),
161 		.length		= PCIMEM_SIZE,
162 		.type		= MT_DEVICE,
163 	}, {
164 		.virtual	= PCICFG0_BASE,
165 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_0_CONFIG),
166 		.length		= PCICFG0_SIZE,
167 		.type		= MT_DEVICE,
168 	}, {
169 		.virtual	= PCICFG1_BASE,
170 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_1_CONFIG),
171 		.length		= PCICFG1_SIZE,
172 		.type		= MT_DEVICE,
173 	}, {
174 		.virtual	= PCIIACK_BASE,
175 		.pfn		= __phys_to_pfn(DC21285_PCI_IACK),
176 		.length		= PCIIACK_SIZE,
177 		.type		= MT_DEVICE,
178 	}, {
179 		.virtual	= PCIO_BASE,
180 		.pfn		= __phys_to_pfn(DC21285_PCI_IO),
181 		.length		= PCIO_SIZE,
182 		.type		= MT_DEVICE,
183 	},
184 #endif
185 };
186 
187 void __init footbridge_map_io(void)
188 {
189 	/*
190 	 * Set up the common mapping first; we need this to
191 	 * determine whether we're in host mode or not.
192 	 */
193 	iotable_init(fb_common_io_desc, ARRAY_SIZE(fb_common_io_desc));
194 
195 	/*
196 	 * Now, work out what we've got to map in addition on this
197 	 * platform.
198 	 */
199 	if (footbridge_cfn_mode())
200 		iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
201 }
202 
203 void footbridge_restart(char mode, const char *cmd)
204 {
205 	if (mode == 's') {
206 		/* Jump into the ROM */
207 		soft_restart(0x41000000);
208 	} else {
209 		/*
210 		 * Force the watchdog to do a CPU reset.
211 		 *
212 		 * After making sure that the watchdog is disabled
213 		 * (so we can change the timer registers) we first
214 		 * enable the timer to autoreload itself.  Next, the
215 		 * timer interval is set really short and any
216 		 * current interrupt request is cleared (so we can
217 		 * see an edge transition).  Finally, TIMER4 is
218 		 * enabled as the watchdog.
219 		 */
220 		*CSR_SA110_CNTL &= ~(1 << 13);
221 		*CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE |
222 				   TIMER_CNTL_AUTORELOAD |
223 				   TIMER_CNTL_DIV16;
224 		*CSR_TIMER4_LOAD = 0x2;
225 		*CSR_TIMER4_CLR  = 0;
226 		*CSR_SA110_CNTL |= (1 << 13);
227 	}
228 }
229 
230 #ifdef CONFIG_FOOTBRIDGE_ADDIN
231 
232 static inline unsigned long fb_bus_sdram_offset(void)
233 {
234 	return *CSR_PCISDRAMBASE & 0xfffffff0;
235 }
236 
237 /*
238  * These two functions convert virtual addresses to PCI addresses and PCI
239  * addresses to virtual addresses.  Note that it is only legal to use these
240  * on memory obtained via get_zeroed_page or kmalloc.
241  */
242 unsigned long __virt_to_bus(unsigned long res)
243 {
244 	WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
245 
246 	return res + (fb_bus_sdram_offset() - PAGE_OFFSET);
247 }
248 EXPORT_SYMBOL(__virt_to_bus);
249 
250 unsigned long __bus_to_virt(unsigned long res)
251 {
252 	res = res - (fb_bus_sdram_offset() - PAGE_OFFSET);
253 
254 	WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
255 
256 	return res;
257 }
258 EXPORT_SYMBOL(__bus_to_virt);
259 
260 unsigned long __pfn_to_bus(unsigned long pfn)
261 {
262 	return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET);
263 }
264 EXPORT_SYMBOL(__pfn_to_bus);
265 
266 unsigned long __bus_to_pfn(unsigned long bus)
267 {
268 	return __phys_to_pfn(bus - (fb_bus_sdram_offset() - PHYS_OFFSET));
269 }
270 EXPORT_SYMBOL(__bus_to_pfn);
271 
272 #endif
273