1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/arch/arm/mach-footbridge/common.c
4  *
5  *  Copyright (C) 1998-2000 Russell King, Dave Gilbert.
6  */
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/mm.h>
10 #include <linux/ioport.h>
11 #include <linux/list.h>
12 #include <linux/init.h>
13 #include <linux/io.h>
14 #include <linux/spinlock.h>
15 #include <video/vga.h>
16 
17 #include <asm/page.h>
18 #include <asm/irq.h>
19 #include <asm/mach-types.h>
20 #include <asm/setup.h>
21 #include <asm/system_misc.h>
22 #include <asm/hardware/dec21285.h>
23 
24 #include <asm/mach/irq.h>
25 #include <asm/mach/map.h>
26 #include <asm/mach/pci.h>
27 
28 #include "common.h"
29 
30 #include <mach/hardware.h>
31 #include <mach/irqs.h>
32 #include <asm/hardware/dec21285.h>
33 
34 static int dc21285_get_irq(void)
35 {
36 	void __iomem *irqstatus = (void __iomem *)CSR_IRQ_STATUS;
37 	u32 mask = readl(irqstatus);
38 
39 	if (mask & IRQ_MASK_SDRAMPARITY)
40 		return IRQ_SDRAMPARITY;
41 
42 	if (mask & IRQ_MASK_UART_RX)
43 		return IRQ_CONRX;
44 
45 	if (mask & IRQ_MASK_DMA1)
46 		return IRQ_DMA1;
47 
48 	if (mask & IRQ_MASK_DMA2)
49 		return IRQ_DMA2;
50 
51 	if (mask & IRQ_MASK_IN0)
52 		return IRQ_IN0;
53 
54 	if (mask & IRQ_MASK_IN1)
55 		return IRQ_IN1;
56 
57 	if (mask & IRQ_MASK_IN2)
58 		return IRQ_IN2;
59 
60 	if (mask & IRQ_MASK_IN3)
61 		return IRQ_IN3;
62 
63 	if (mask & IRQ_MASK_PCI)
64 		return IRQ_PCI;
65 
66 	if (mask & IRQ_MASK_DOORBELLHOST)
67 		return IRQ_DOORBELLHOST;
68 
69 	if (mask & IRQ_MASK_I2OINPOST)
70 		return IRQ_I2OINPOST;
71 
72 	if (mask & IRQ_MASK_TIMER1)
73 		return IRQ_TIMER1;
74 
75 	if (mask & IRQ_MASK_TIMER2)
76 		return IRQ_TIMER2;
77 
78 	if (mask & IRQ_MASK_TIMER3)
79 		return IRQ_TIMER3;
80 
81 	if (mask & IRQ_MASK_UART_TX)
82 		return IRQ_CONTX;
83 
84 	if (mask & IRQ_MASK_PCI_ABORT)
85 		return IRQ_PCI_ABORT;
86 
87 	if (mask & IRQ_MASK_PCI_SERR)
88 		return IRQ_PCI_SERR;
89 
90 	if (mask & IRQ_MASK_DISCARD_TIMER)
91 		return IRQ_DISCARD_TIMER;
92 
93 	if (mask & IRQ_MASK_PCI_DPERR)
94 		return IRQ_PCI_DPERR;
95 
96 	if (mask & IRQ_MASK_PCI_PERR)
97 		return IRQ_PCI_PERR;
98 
99 	return 0;
100 }
101 
102 static void dc21285_handle_irq(struct pt_regs *regs)
103 {
104 	int irq;
105 	do {
106 		irq = dc21285_get_irq();
107 		if (!irq)
108 			break;
109 
110 		generic_handle_irq(irq);
111 	} while (1);
112 }
113 
114 
115 unsigned int mem_fclk_21285 = 50000000;
116 
117 EXPORT_SYMBOL(mem_fclk_21285);
118 
119 static int __init early_fclk(char *arg)
120 {
121 	mem_fclk_21285 = simple_strtoul(arg, NULL, 0);
122 	return 0;
123 }
124 
125 early_param("mem_fclk_21285", early_fclk);
126 
127 static int __init parse_tag_memclk(const struct tag *tag)
128 {
129 	mem_fclk_21285 = tag->u.memclk.fmemclk;
130 	return 0;
131 }
132 
133 __tagtable(ATAG_MEMCLK, parse_tag_memclk);
134 
135 /*
136  * Footbridge IRQ translation table
137  *  Converts from our IRQ numbers into FootBridge masks
138  */
139 static const int fb_irq_mask[] = {
140 	IRQ_MASK_UART_RX,	/*  0 */
141 	IRQ_MASK_UART_TX,	/*  1 */
142 	IRQ_MASK_TIMER1,	/*  2 */
143 	IRQ_MASK_TIMER2,	/*  3 */
144 	IRQ_MASK_TIMER3,	/*  4 */
145 	IRQ_MASK_IN0,		/*  5 */
146 	IRQ_MASK_IN1,		/*  6 */
147 	IRQ_MASK_IN2,		/*  7 */
148 	IRQ_MASK_IN3,		/*  8 */
149 	IRQ_MASK_DOORBELLHOST,	/*  9 */
150 	IRQ_MASK_DMA1,		/* 10 */
151 	IRQ_MASK_DMA2,		/* 11 */
152 	IRQ_MASK_PCI,		/* 12 */
153 	IRQ_MASK_SDRAMPARITY,	/* 13 */
154 	IRQ_MASK_I2OINPOST,	/* 14 */
155 	IRQ_MASK_PCI_ABORT,	/* 15 */
156 	IRQ_MASK_PCI_SERR,	/* 16 */
157 	IRQ_MASK_DISCARD_TIMER,	/* 17 */
158 	IRQ_MASK_PCI_DPERR,	/* 18 */
159 	IRQ_MASK_PCI_PERR,	/* 19 */
160 };
161 
162 static void fb_mask_irq(struct irq_data *d)
163 {
164 	*CSR_IRQ_DISABLE = fb_irq_mask[_DC21285_INR(d->irq)];
165 }
166 
167 static void fb_unmask_irq(struct irq_data *d)
168 {
169 	*CSR_IRQ_ENABLE = fb_irq_mask[_DC21285_INR(d->irq)];
170 }
171 
172 static struct irq_chip fb_chip = {
173 	.irq_ack	= fb_mask_irq,
174 	.irq_mask	= fb_mask_irq,
175 	.irq_unmask	= fb_unmask_irq,
176 };
177 
178 static void __init __fb_init_irq(void)
179 {
180 	unsigned int irq;
181 
182 	/*
183 	 * setup DC21285 IRQs
184 	 */
185 	*CSR_IRQ_DISABLE = -1;
186 	*CSR_FIQ_DISABLE = -1;
187 
188 	for (irq = _DC21285_IRQ(0); irq < _DC21285_IRQ(20); irq++) {
189 		irq_set_chip_and_handler(irq, &fb_chip, handle_level_irq);
190 		irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);
191 	}
192 }
193 
194 void __init footbridge_init_irq(void)
195 {
196 	set_handle_irq(dc21285_handle_irq);
197 
198 	__fb_init_irq();
199 
200 	if (!footbridge_cfn_mode())
201 		return;
202 
203 	if (machine_is_ebsa285())
204 		/* The following is dependent on which slot
205 		 * you plug the Southbridge card into.  We
206 		 * currently assume that you plug it into
207 		 * the right-hand most slot.
208 		 */
209 		isa_init_irq(IRQ_PCI);
210 
211 	if (machine_is_cats())
212 		isa_init_irq(IRQ_IN2);
213 
214 	if (machine_is_netwinder())
215 		isa_init_irq(IRQ_IN3);
216 }
217 
218 /*
219  * Common mapping for all systems.  Note that the outbound write flush is
220  * commented out since there is a "No Fix" problem with it.  Not mapping
221  * it means that we have extra bullet protection on our feet.
222  */
223 static struct map_desc fb_common_io_desc[] __initdata = {
224 	{
225 		.virtual	= ARMCSR_BASE,
226 		.pfn		= __phys_to_pfn(DC21285_ARMCSR_BASE),
227 		.length		= ARMCSR_SIZE,
228 		.type		= MT_DEVICE,
229 	}
230 };
231 
232 /*
233  * The mapping when the footbridge is in host mode.  We don't map any of
234  * this when we are in add-in mode.
235  */
236 static struct map_desc ebsa285_host_io_desc[] __initdata = {
237 #if defined(CONFIG_ARCH_FOOTBRIDGE) && defined(CONFIG_FOOTBRIDGE_HOST)
238 	{
239 		.virtual	= PCIMEM_BASE,
240 		.pfn		= __phys_to_pfn(DC21285_PCI_MEM),
241 		.length		= PCIMEM_SIZE,
242 		.type		= MT_DEVICE,
243 	}, {
244 		.virtual	= PCICFG0_BASE,
245 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_0_CONFIG),
246 		.length		= PCICFG0_SIZE,
247 		.type		= MT_DEVICE,
248 	}, {
249 		.virtual	= PCICFG1_BASE,
250 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_1_CONFIG),
251 		.length		= PCICFG1_SIZE,
252 		.type		= MT_DEVICE,
253 	}, {
254 		.virtual	= PCIIACK_BASE,
255 		.pfn		= __phys_to_pfn(DC21285_PCI_IACK),
256 		.length		= PCIIACK_SIZE,
257 		.type		= MT_DEVICE,
258 	},
259 #endif
260 };
261 
262 void __init footbridge_map_io(void)
263 {
264 	/*
265 	 * Set up the common mapping first; we need this to
266 	 * determine whether we're in host mode or not.
267 	 */
268 	iotable_init(fb_common_io_desc, ARRAY_SIZE(fb_common_io_desc));
269 
270 	/*
271 	 * Now, work out what we've got to map in addition on this
272 	 * platform.
273 	 */
274 	if (footbridge_cfn_mode()) {
275 		iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
276 		pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
277 	}
278 
279 	vga_base = PCIMEM_BASE;
280 }
281 
282 void footbridge_restart(enum reboot_mode mode, const char *cmd)
283 {
284 	if (mode == REBOOT_SOFT) {
285 		/* Jump into the ROM */
286 		soft_restart(0x41000000);
287 	} else {
288 		/*
289 		 * Force the watchdog to do a CPU reset.
290 		 *
291 		 * After making sure that the watchdog is disabled
292 		 * (so we can change the timer registers) we first
293 		 * enable the timer to autoreload itself.  Next, the
294 		 * timer interval is set really short and any
295 		 * current interrupt request is cleared (so we can
296 		 * see an edge transition).  Finally, TIMER4 is
297 		 * enabled as the watchdog.
298 		 */
299 		*CSR_SA110_CNTL &= ~(1 << 13);
300 		*CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE |
301 				   TIMER_CNTL_AUTORELOAD |
302 				   TIMER_CNTL_DIV16;
303 		*CSR_TIMER4_LOAD = 0x2;
304 		*CSR_TIMER4_CLR  = 0;
305 		*CSR_SA110_CNTL |= (1 << 13);
306 	}
307 }
308 
309 #ifdef CONFIG_FOOTBRIDGE_ADDIN
310 
311 static inline unsigned long fb_bus_sdram_offset(void)
312 {
313 	return *CSR_PCISDRAMBASE & 0xfffffff0;
314 }
315 
316 /*
317  * These two functions convert virtual addresses to PCI addresses and PCI
318  * addresses to virtual addresses.  Note that it is only legal to use these
319  * on memory obtained via get_zeroed_page or kmalloc.
320  */
321 unsigned long __virt_to_bus(unsigned long res)
322 {
323 	WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
324 
325 	return res + (fb_bus_sdram_offset() - PAGE_OFFSET);
326 }
327 EXPORT_SYMBOL(__virt_to_bus);
328 
329 unsigned long __bus_to_virt(unsigned long res)
330 {
331 	res = res - (fb_bus_sdram_offset() - PAGE_OFFSET);
332 
333 	WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory);
334 
335 	return res;
336 }
337 EXPORT_SYMBOL(__bus_to_virt);
338 
339 unsigned long __pfn_to_bus(unsigned long pfn)
340 {
341 	return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET);
342 }
343 EXPORT_SYMBOL(__pfn_to_bus);
344 
345 unsigned long __bus_to_pfn(unsigned long bus)
346 {
347 	return __phys_to_pfn(bus - (fb_bus_sdram_offset() - PHYS_OFFSET));
348 }
349 EXPORT_SYMBOL(__bus_to_pfn);
350 
351 #endif
352