xref: /openbmc/linux/arch/mips/ath25/ar5312.c (revision 842ed298)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
7  * Copyright (C) 2006 FON Technology, SL.
8  * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
9  * Copyright (C) 2006-2009 Felix Fietkau <nbd@openwrt.org>
10  * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com>
11  */
12 
13 /*
14  * Platform devices for Atheros AR5312 SoCs
15  */
16 
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/bitops.h>
20 #include <linux/irqdomain.h>
21 #include <linux/interrupt.h>
22 #include <linux/memblock.h>
23 #include <linux/platform_device.h>
24 #include <linux/mtd/physmap.h>
25 #include <linux/reboot.h>
26 #include <asm/bootinfo.h>
27 #include <asm/reboot.h>
28 #include <asm/time.h>
29 
30 #include <ath25_platform.h>
31 
32 #include "devices.h"
33 #include "ar5312.h"
34 #include "ar5312_regs.h"
35 
36 static void __iomem *ar5312_rst_base;
37 static struct irq_domain *ar5312_misc_irq_domain;
38 
39 static inline u32 ar5312_rst_reg_read(u32 reg)
40 {
41 	return __raw_readl(ar5312_rst_base + reg);
42 }
43 
44 static inline void ar5312_rst_reg_write(u32 reg, u32 val)
45 {
46 	__raw_writel(val, ar5312_rst_base + reg);
47 }
48 
49 static inline void ar5312_rst_reg_mask(u32 reg, u32 mask, u32 val)
50 {
51 	u32 ret = ar5312_rst_reg_read(reg);
52 
53 	ret &= ~mask;
54 	ret |= val;
55 	ar5312_rst_reg_write(reg, ret);
56 }
57 
58 static irqreturn_t ar5312_ahb_err_handler(int cpl, void *dev_id)
59 {
60 	u32 proc1 = ar5312_rst_reg_read(AR5312_PROC1);
61 	u32 proc_addr = ar5312_rst_reg_read(AR5312_PROCADDR); /* clears error */
62 	u32 dma1 = ar5312_rst_reg_read(AR5312_DMA1);
63 	u32 dma_addr = ar5312_rst_reg_read(AR5312_DMAADDR);   /* clears error */
64 
65 	pr_emerg("AHB interrupt: PROCADDR=0x%8.8x PROC1=0x%8.8x DMAADDR=0x%8.8x DMA1=0x%8.8x\n",
66 		 proc_addr, proc1, dma_addr, dma1);
67 
68 	machine_restart("AHB error"); /* Catastrophic failure */
69 	return IRQ_HANDLED;
70 }
71 
72 static void ar5312_misc_irq_handler(struct irq_desc *desc)
73 {
74 	u32 pending = ar5312_rst_reg_read(AR5312_ISR) &
75 		      ar5312_rst_reg_read(AR5312_IMR);
76 	unsigned nr, misc_irq = 0;
77 
78 	if (pending) {
79 		struct irq_domain *domain = irq_desc_get_handler_data(desc);
80 
81 		nr = __ffs(pending);
82 		misc_irq = irq_find_mapping(domain, nr);
83 	}
84 
85 	if (misc_irq) {
86 		generic_handle_irq(misc_irq);
87 		if (nr == AR5312_MISC_IRQ_TIMER)
88 			ar5312_rst_reg_read(AR5312_TIMER);
89 	} else {
90 		spurious_interrupt();
91 	}
92 }
93 
94 /* Enable the specified AR5312_MISC_IRQ interrupt */
95 static void ar5312_misc_irq_unmask(struct irq_data *d)
96 {
97 	ar5312_rst_reg_mask(AR5312_IMR, 0, BIT(d->hwirq));
98 }
99 
100 /* Disable the specified AR5312_MISC_IRQ interrupt */
101 static void ar5312_misc_irq_mask(struct irq_data *d)
102 {
103 	ar5312_rst_reg_mask(AR5312_IMR, BIT(d->hwirq), 0);
104 	ar5312_rst_reg_read(AR5312_IMR); /* flush write buffer */
105 }
106 
107 static struct irq_chip ar5312_misc_irq_chip = {
108 	.name		= "ar5312-misc",
109 	.irq_unmask	= ar5312_misc_irq_unmask,
110 	.irq_mask	= ar5312_misc_irq_mask,
111 };
112 
113 static int ar5312_misc_irq_map(struct irq_domain *d, unsigned irq,
114 			       irq_hw_number_t hw)
115 {
116 	irq_set_chip_and_handler(irq, &ar5312_misc_irq_chip, handle_level_irq);
117 	return 0;
118 }
119 
120 static struct irq_domain_ops ar5312_misc_irq_domain_ops = {
121 	.map = ar5312_misc_irq_map,
122 };
123 
124 static void ar5312_irq_dispatch(void)
125 {
126 	u32 pending = read_c0_status() & read_c0_cause();
127 
128 	if (pending & CAUSEF_IP2)
129 		do_IRQ(AR5312_IRQ_WLAN0);
130 	else if (pending & CAUSEF_IP5)
131 		do_IRQ(AR5312_IRQ_WLAN1);
132 	else if (pending & CAUSEF_IP6)
133 		do_IRQ(AR5312_IRQ_MISC);
134 	else if (pending & CAUSEF_IP7)
135 		do_IRQ(ATH25_IRQ_CPU_CLOCK);
136 	else
137 		spurious_interrupt();
138 }
139 
140 void __init ar5312_arch_init_irq(void)
141 {
142 	struct irq_domain *domain;
143 	unsigned irq;
144 
145 	ath25_irq_dispatch = ar5312_irq_dispatch;
146 
147 	domain = irq_domain_add_linear(NULL, AR5312_MISC_IRQ_COUNT,
148 				       &ar5312_misc_irq_domain_ops, NULL);
149 	if (!domain)
150 		panic("Failed to add IRQ domain");
151 
152 	irq = irq_create_mapping(domain, AR5312_MISC_IRQ_AHB_PROC);
153 	if (request_irq(irq, ar5312_ahb_err_handler, 0, "ar5312-ahb-error",
154 			NULL))
155 		pr_err("Failed to register ar5312-ahb-error interrupt\n");
156 
157 	irq_set_chained_handler_and_data(AR5312_IRQ_MISC,
158 					 ar5312_misc_irq_handler, domain);
159 
160 	ar5312_misc_irq_domain = domain;
161 }
162 
163 static struct physmap_flash_data ar5312_flash_data = {
164 	.width = 2,
165 };
166 
167 static struct resource ar5312_flash_resource = {
168 	.start = AR5312_FLASH_BASE,
169 	.end = AR5312_FLASH_BASE + AR5312_FLASH_SIZE - 1,
170 	.flags = IORESOURCE_MEM,
171 };
172 
173 static struct platform_device ar5312_physmap_flash = {
174 	.name = "physmap-flash",
175 	.id = 0,
176 	.dev.platform_data = &ar5312_flash_data,
177 	.resource = &ar5312_flash_resource,
178 	.num_resources = 1,
179 };
180 
181 static void __init ar5312_flash_init(void)
182 {
183 	void __iomem *flashctl_base;
184 	u32 ctl;
185 
186 	flashctl_base = ioremap(AR5312_FLASHCTL_BASE,
187 					AR5312_FLASHCTL_SIZE);
188 
189 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL0);
190 	ctl &= AR5312_FLASHCTL_MW;
191 
192 	/* fixup flash width */
193 	switch (ctl) {
194 	case AR5312_FLASHCTL_MW16:
195 		ar5312_flash_data.width = 2;
196 		break;
197 	case AR5312_FLASHCTL_MW8:
198 	default:
199 		ar5312_flash_data.width = 1;
200 		break;
201 	}
202 
203 	/*
204 	 * Configure flash bank 0.
205 	 * Assume 8M window size. Flash will be aliased if it's smaller
206 	 */
207 	ctl |= AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC_8M | AR5312_FLASHCTL_RBLE;
208 	ctl |= 0x01 << AR5312_FLASHCTL_IDCY_S;
209 	ctl |= 0x07 << AR5312_FLASHCTL_WST1_S;
210 	ctl |= 0x07 << AR5312_FLASHCTL_WST2_S;
211 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL0);
212 
213 	/* Disable other flash banks */
214 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL1);
215 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
216 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL1);
217 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL2);
218 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
219 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL2);
220 
221 	iounmap(flashctl_base);
222 }
223 
224 void __init ar5312_init_devices(void)
225 {
226 	struct ath25_boarddata *config;
227 
228 	ar5312_flash_init();
229 
230 	/* Locate board/radio config data */
231 	ath25_find_config(AR5312_FLASH_BASE, AR5312_FLASH_SIZE);
232 	config = ath25_board.config;
233 
234 	/* AR2313 has CPU minor rev. 10 */
235 	if ((current_cpu_data.processor_id & 0xff) == 0x0a)
236 		ath25_soc = ATH25_SOC_AR2313;
237 
238 	/* AR2312 shares the same Silicon ID as AR5312 */
239 	else if (config->flags & BD_ISCASPER)
240 		ath25_soc = ATH25_SOC_AR2312;
241 
242 	/* Everything else is probably AR5312 or compatible */
243 	else
244 		ath25_soc = ATH25_SOC_AR5312;
245 
246 	platform_device_register(&ar5312_physmap_flash);
247 
248 	switch (ath25_soc) {
249 	case ATH25_SOC_AR5312:
250 		if (!ath25_board.radio)
251 			return;
252 
253 		if (!(config->flags & BD_WLAN0))
254 			break;
255 
256 		ath25_add_wmac(0, AR5312_WLAN0_BASE, AR5312_IRQ_WLAN0);
257 		break;
258 	case ATH25_SOC_AR2312:
259 	case ATH25_SOC_AR2313:
260 		if (!ath25_board.radio)
261 			return;
262 		break;
263 	default:
264 		break;
265 	}
266 
267 	if (config->flags & BD_WLAN1)
268 		ath25_add_wmac(1, AR5312_WLAN1_BASE, AR5312_IRQ_WLAN1);
269 }
270 
271 static void ar5312_restart(char *command)
272 {
273 	/* reset the system */
274 	local_irq_disable();
275 	while (1)
276 		ar5312_rst_reg_write(AR5312_RESET, AR5312_RESET_SYSTEM);
277 }
278 
279 /*
280  * This table is indexed by bits 5..4 of the CLOCKCTL1 register
281  * to determine the predevisor value.
282  */
283 static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
284 
285 static unsigned __init ar5312_cpu_frequency(void)
286 {
287 	u32 scratch, devid, clock_ctl1;
288 	u32 predivide_mask, multiplier_mask, doubler_mask;
289 	unsigned predivide_shift, multiplier_shift;
290 	unsigned predivide_select, predivisor, multiplier;
291 
292 	/* Trust the bootrom's idea of cpu frequency. */
293 	scratch = ar5312_rst_reg_read(AR5312_SCRATCH);
294 	if (scratch)
295 		return scratch;
296 
297 	devid = ar5312_rst_reg_read(AR5312_REV);
298 	devid = (devid & AR5312_REV_MAJ) >> AR5312_REV_MAJ_S;
299 	if (devid == AR5312_REV_MAJ_AR2313) {
300 		predivide_mask = AR2313_CLOCKCTL1_PREDIVIDE_MASK;
301 		predivide_shift = AR2313_CLOCKCTL1_PREDIVIDE_SHIFT;
302 		multiplier_mask = AR2313_CLOCKCTL1_MULTIPLIER_MASK;
303 		multiplier_shift = AR2313_CLOCKCTL1_MULTIPLIER_SHIFT;
304 		doubler_mask = AR2313_CLOCKCTL1_DOUBLER_MASK;
305 	} else { /* AR5312 and AR2312 */
306 		predivide_mask = AR5312_CLOCKCTL1_PREDIVIDE_MASK;
307 		predivide_shift = AR5312_CLOCKCTL1_PREDIVIDE_SHIFT;
308 		multiplier_mask = AR5312_CLOCKCTL1_MULTIPLIER_MASK;
309 		multiplier_shift = AR5312_CLOCKCTL1_MULTIPLIER_SHIFT;
310 		doubler_mask = AR5312_CLOCKCTL1_DOUBLER_MASK;
311 	}
312 
313 	/*
314 	 * Clocking is derived from a fixed 40MHz input clock.
315 	 *
316 	 *  cpu_freq = input_clock * MULT (where MULT is PLL multiplier)
317 	 *  sys_freq = cpu_freq / 4	  (used for APB clock, serial,
318 	 *				   flash, Timer, Watchdog Timer)
319 	 *
320 	 *  cnt_freq = cpu_freq / 2	  (use for CPU count/compare)
321 	 *
322 	 * So, for example, with a PLL multiplier of 5, we have
323 	 *
324 	 *  cpu_freq = 200MHz
325 	 *  sys_freq = 50MHz
326 	 *  cnt_freq = 100MHz
327 	 *
328 	 * We compute the CPU frequency, based on PLL settings.
329 	 */
330 
331 	clock_ctl1 = ar5312_rst_reg_read(AR5312_CLOCKCTL1);
332 	predivide_select = (clock_ctl1 & predivide_mask) >> predivide_shift;
333 	predivisor = clockctl1_predivide_table[predivide_select];
334 	multiplier = (clock_ctl1 & multiplier_mask) >> multiplier_shift;
335 
336 	if (clock_ctl1 & doubler_mask)
337 		multiplier <<= 1;
338 
339 	return (40000000 / predivisor) * multiplier;
340 }
341 
342 static inline unsigned ar5312_sys_frequency(void)
343 {
344 	return ar5312_cpu_frequency() / 4;
345 }
346 
347 void __init ar5312_plat_time_init(void)
348 {
349 	mips_hpt_frequency = ar5312_cpu_frequency() / 2;
350 }
351 
352 void __init ar5312_plat_mem_setup(void)
353 {
354 	void __iomem *sdram_base;
355 	u32 memsize, memcfg, bank0_ac, bank1_ac;
356 	u32 devid;
357 
358 	/* Detect memory size */
359 	sdram_base = ioremap(AR5312_SDRAMCTL_BASE,
360 				     AR5312_SDRAMCTL_SIZE);
361 	memcfg = __raw_readl(sdram_base + AR5312_MEM_CFG1);
362 	bank0_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC0);
363 	bank1_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC1);
364 	memsize = (bank0_ac ? (1 << (bank0_ac + 1)) : 0) +
365 		  (bank1_ac ? (1 << (bank1_ac + 1)) : 0);
366 	memsize <<= 20;
367 	memblock_add(0, memsize);
368 	iounmap(sdram_base);
369 
370 	ar5312_rst_base = ioremap(AR5312_RST_BASE, AR5312_RST_SIZE);
371 
372 	devid = ar5312_rst_reg_read(AR5312_REV);
373 	devid >>= AR5312_REV_WMAC_MIN_S;
374 	devid &= AR5312_REV_CHIP;
375 	ath25_board.devid = (u16)devid;
376 
377 	/* Clear any lingering AHB errors */
378 	ar5312_rst_reg_read(AR5312_PROCADDR);
379 	ar5312_rst_reg_read(AR5312_DMAADDR);
380 	ar5312_rst_reg_write(AR5312_WDT_CTRL, AR5312_WDT_CTRL_IGNORE);
381 
382 	_machine_restart = ar5312_restart;
383 }
384 
385 void __init ar5312_arch_init(void)
386 {
387 	unsigned irq = irq_create_mapping(ar5312_misc_irq_domain,
388 					  AR5312_MISC_IRQ_UART0);
389 
390 	ath25_serial_setup(AR5312_UART0_BASE, irq, ar5312_sys_frequency());
391 }
392