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 <linux/dma-direct.h>
16 #include <video/vga.h>
17 
18 #include <asm/page.h>
19 #include <asm/irq.h>
20 #include <asm/mach-types.h>
21 #include <asm/setup.h>
22 #include <asm/system_misc.h>
23 #include <asm/hardware/dec21285.h>
24 
25 #include <asm/mach/irq.h>
26 #include <asm/mach/map.h>
27 #include <asm/mach/pci.h>
28 
29 #include "common.h"
30 
31 #include <mach/hardware.h>
32 #include <mach/irqs.h>
33 #include <asm/hardware/dec21285.h>
34 
35 static int dc21285_get_irq(void)
36 {
37 	void __iomem *irqstatus = (void __iomem *)CSR_IRQ_STATUS;
38 	u32 mask = readl(irqstatus);
39 
40 	if (mask & IRQ_MASK_SDRAMPARITY)
41 		return IRQ_SDRAMPARITY;
42 
43 	if (mask & IRQ_MASK_UART_RX)
44 		return IRQ_CONRX;
45 
46 	if (mask & IRQ_MASK_DMA1)
47 		return IRQ_DMA1;
48 
49 	if (mask & IRQ_MASK_DMA2)
50 		return IRQ_DMA2;
51 
52 	if (mask & IRQ_MASK_IN0)
53 		return IRQ_IN0;
54 
55 	if (mask & IRQ_MASK_IN1)
56 		return IRQ_IN1;
57 
58 	if (mask & IRQ_MASK_IN2)
59 		return IRQ_IN2;
60 
61 	if (mask & IRQ_MASK_IN3)
62 		return IRQ_IN3;
63 
64 	if (mask & IRQ_MASK_PCI)
65 		return IRQ_PCI;
66 
67 	if (mask & IRQ_MASK_DOORBELLHOST)
68 		return IRQ_DOORBELLHOST;
69 
70 	if (mask & IRQ_MASK_I2OINPOST)
71 		return IRQ_I2OINPOST;
72 
73 	if (mask & IRQ_MASK_TIMER1)
74 		return IRQ_TIMER1;
75 
76 	if (mask & IRQ_MASK_TIMER2)
77 		return IRQ_TIMER2;
78 
79 	if (mask & IRQ_MASK_TIMER3)
80 		return IRQ_TIMER3;
81 
82 	if (mask & IRQ_MASK_UART_TX)
83 		return IRQ_CONTX;
84 
85 	if (mask & IRQ_MASK_PCI_ABORT)
86 		return IRQ_PCI_ABORT;
87 
88 	if (mask & IRQ_MASK_PCI_SERR)
89 		return IRQ_PCI_SERR;
90 
91 	if (mask & IRQ_MASK_DISCARD_TIMER)
92 		return IRQ_DISCARD_TIMER;
93 
94 	if (mask & IRQ_MASK_PCI_DPERR)
95 		return IRQ_PCI_DPERR;
96 
97 	if (mask & IRQ_MASK_PCI_PERR)
98 		return IRQ_PCI_PERR;
99 
100 	return 0;
101 }
102 
103 static void dc21285_handle_irq(struct pt_regs *regs)
104 {
105 	int irq;
106 	do {
107 		irq = dc21285_get_irq();
108 		if (!irq)
109 			break;
110 
111 		generic_handle_irq(irq);
112 	} while (1);
113 }
114 
115 
116 unsigned int mem_fclk_21285 = 50000000;
117 
118 EXPORT_SYMBOL(mem_fclk_21285);
119 
120 static int __init early_fclk(char *arg)
121 {
122 	mem_fclk_21285 = simple_strtoul(arg, NULL, 0);
123 	return 0;
124 }
125 
126 early_param("mem_fclk_21285", early_fclk);
127 
128 static int __init parse_tag_memclk(const struct tag *tag)
129 {
130 	mem_fclk_21285 = tag->u.memclk.fmemclk;
131 	return 0;
132 }
133 
134 __tagtable(ATAG_MEMCLK, parse_tag_memclk);
135 
136 /*
137  * Footbridge IRQ translation table
138  *  Converts from our IRQ numbers into FootBridge masks
139  */
140 static const int fb_irq_mask[] = {
141 	IRQ_MASK_UART_RX,	/*  0 */
142 	IRQ_MASK_UART_TX,	/*  1 */
143 	IRQ_MASK_TIMER1,	/*  2 */
144 	IRQ_MASK_TIMER2,	/*  3 */
145 	IRQ_MASK_TIMER3,	/*  4 */
146 	IRQ_MASK_IN0,		/*  5 */
147 	IRQ_MASK_IN1,		/*  6 */
148 	IRQ_MASK_IN2,		/*  7 */
149 	IRQ_MASK_IN3,		/*  8 */
150 	IRQ_MASK_DOORBELLHOST,	/*  9 */
151 	IRQ_MASK_DMA1,		/* 10 */
152 	IRQ_MASK_DMA2,		/* 11 */
153 	IRQ_MASK_PCI,		/* 12 */
154 	IRQ_MASK_SDRAMPARITY,	/* 13 */
155 	IRQ_MASK_I2OINPOST,	/* 14 */
156 	IRQ_MASK_PCI_ABORT,	/* 15 */
157 	IRQ_MASK_PCI_SERR,	/* 16 */
158 	IRQ_MASK_DISCARD_TIMER,	/* 17 */
159 	IRQ_MASK_PCI_DPERR,	/* 18 */
160 	IRQ_MASK_PCI_PERR,	/* 19 */
161 };
162 
163 static void fb_mask_irq(struct irq_data *d)
164 {
165 	*CSR_IRQ_DISABLE = fb_irq_mask[_DC21285_INR(d->irq)];
166 }
167 
168 static void fb_unmask_irq(struct irq_data *d)
169 {
170 	*CSR_IRQ_ENABLE = fb_irq_mask[_DC21285_INR(d->irq)];
171 }
172 
173 static struct irq_chip fb_chip = {
174 	.irq_ack	= fb_mask_irq,
175 	.irq_mask	= fb_mask_irq,
176 	.irq_unmask	= fb_unmask_irq,
177 };
178 
179 static void __init __fb_init_irq(void)
180 {
181 	unsigned int irq;
182 
183 	/*
184 	 * setup DC21285 IRQs
185 	 */
186 	*CSR_IRQ_DISABLE = -1;
187 	*CSR_FIQ_DISABLE = -1;
188 
189 	for (irq = _DC21285_IRQ(0); irq < _DC21285_IRQ(20); irq++) {
190 		irq_set_chip_and_handler(irq, &fb_chip, handle_level_irq);
191 		irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);
192 	}
193 }
194 
195 void __init footbridge_init_irq(void)
196 {
197 	set_handle_irq(dc21285_handle_irq);
198 
199 	__fb_init_irq();
200 
201 	if (machine_is_ebsa285())
202 		/* The following is dependent on which slot
203 		 * you plug the Southbridge card into.  We
204 		 * currently assume that you plug it into
205 		 * the right-hand most slot.
206 		 */
207 		isa_init_irq(IRQ_PCI);
208 
209 	if (machine_is_netwinder())
210 		isa_init_irq(IRQ_IN3);
211 }
212 
213 /*
214  * Common mapping for all systems.  Note that the outbound write flush is
215  * commented out since there is a "No Fix" problem with it.  Not mapping
216  * it means that we have extra bullet protection on our feet.
217  */
218 static struct map_desc ebsa285_host_io_desc[] __initdata = {
219 	{
220 		.virtual	= ARMCSR_BASE,
221 		.pfn		= __phys_to_pfn(DC21285_ARMCSR_BASE),
222 		.length		= ARMCSR_SIZE,
223 		.type		= MT_DEVICE,
224 	},
225 	{
226 		.virtual	= PCIMEM_BASE,
227 		.pfn		= __phys_to_pfn(DC21285_PCI_MEM),
228 		.length		= PCIMEM_SIZE,
229 		.type		= MT_DEVICE,
230 	}, {
231 		.virtual	= PCICFG0_BASE,
232 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_0_CONFIG),
233 		.length		= PCICFG0_SIZE,
234 		.type		= MT_DEVICE,
235 	}, {
236 		.virtual	= PCICFG1_BASE,
237 		.pfn		= __phys_to_pfn(DC21285_PCI_TYPE_1_CONFIG),
238 		.length		= PCICFG1_SIZE,
239 		.type		= MT_DEVICE,
240 	}, {
241 		.virtual	= PCIIACK_BASE,
242 		.pfn		= __phys_to_pfn(DC21285_PCI_IACK),
243 		.length		= PCIIACK_SIZE,
244 		.type		= MT_DEVICE,
245 	},
246 };
247 
248 void __init footbridge_map_io(void)
249 {
250 	iotable_init(ebsa285_host_io_desc, ARRAY_SIZE(ebsa285_host_io_desc));
251 	pci_map_io_early(__phys_to_pfn(DC21285_PCI_IO));
252 	vga_base = PCIMEM_BASE;
253 }
254 
255 void footbridge_restart(enum reboot_mode mode, const char *cmd)
256 {
257 	if (mode == REBOOT_SOFT) {
258 		/* Jump into the ROM */
259 		soft_restart(0x41000000);
260 	} else {
261 		/*
262 		 * Force the watchdog to do a CPU reset.
263 		 *
264 		 * After making sure that the watchdog is disabled
265 		 * (so we can change the timer registers) we first
266 		 * enable the timer to autoreload itself.  Next, the
267 		 * timer interval is set really short and any
268 		 * current interrupt request is cleared (so we can
269 		 * see an edge transition).  Finally, TIMER4 is
270 		 * enabled as the watchdog.
271 		 */
272 		*CSR_SA110_CNTL &= ~(1 << 13);
273 		*CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE |
274 				   TIMER_CNTL_AUTORELOAD |
275 				   TIMER_CNTL_DIV16;
276 		*CSR_TIMER4_LOAD = 0x2;
277 		*CSR_TIMER4_CLR  = 0;
278 		*CSR_SA110_CNTL |= (1 << 13);
279 	}
280 }
281