xref: /linux/arch/mips/ath25/ar5312.c (revision ef815d2cba782e96b9aad9483523d474ed41c62a)
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;
77 	int ret = 0;
78 
79 	if (pending) {
80 		struct irq_domain *domain = irq_desc_get_handler_data(desc);
81 
82 		nr = __ffs(pending);
83 
84 		ret = generic_handle_domain_irq(domain, nr);
85 		if (nr == AR5312_MISC_IRQ_TIMER)
86 			ar5312_rst_reg_read(AR5312_TIMER);
87 	}
88 
89 	if (!pending || ret)
90 		spurious_interrupt();
91 }
92 
93 /* Enable the specified AR5312_MISC_IRQ interrupt */
94 static void ar5312_misc_irq_unmask(struct irq_data *d)
95 {
96 	ar5312_rst_reg_mask(AR5312_IMR, 0, BIT(d->hwirq));
97 }
98 
99 /* Disable the specified AR5312_MISC_IRQ interrupt */
100 static void ar5312_misc_irq_mask(struct irq_data *d)
101 {
102 	ar5312_rst_reg_mask(AR5312_IMR, BIT(d->hwirq), 0);
103 	ar5312_rst_reg_read(AR5312_IMR); /* flush write buffer */
104 }
105 
106 static struct irq_chip ar5312_misc_irq_chip = {
107 	.name		= "ar5312-misc",
108 	.irq_unmask	= ar5312_misc_irq_unmask,
109 	.irq_mask	= ar5312_misc_irq_mask,
110 };
111 
112 static int ar5312_misc_irq_map(struct irq_domain *d, unsigned irq,
113 			       irq_hw_number_t hw)
114 {
115 	irq_set_chip_and_handler(irq, &ar5312_misc_irq_chip, handle_level_irq);
116 	return 0;
117 }
118 
119 static const struct irq_domain_ops ar5312_misc_irq_domain_ops = {
120 	.map = ar5312_misc_irq_map,
121 };
122 
123 static void ar5312_irq_dispatch(void)
124 {
125 	u32 pending = read_c0_status() & read_c0_cause();
126 
127 	if (pending & CAUSEF_IP2)
128 		do_IRQ(AR5312_IRQ_WLAN0);
129 	else if (pending & CAUSEF_IP5)
130 		do_IRQ(AR5312_IRQ_WLAN1);
131 	else if (pending & CAUSEF_IP6)
132 		do_IRQ(AR5312_IRQ_MISC);
133 	else if (pending & CAUSEF_IP7)
134 		do_IRQ(ATH25_IRQ_CPU_CLOCK);
135 	else
136 		spurious_interrupt();
137 }
138 
139 void __init ar5312_arch_init_irq(void)
140 {
141 	struct irq_domain *domain;
142 	unsigned irq;
143 
144 	ath25_irq_dispatch = ar5312_irq_dispatch;
145 
146 	domain = irq_domain_add_linear(NULL, AR5312_MISC_IRQ_COUNT,
147 				       &ar5312_misc_irq_domain_ops, NULL);
148 	if (!domain)
149 		panic("Failed to add IRQ domain");
150 
151 	irq = irq_create_mapping(domain, AR5312_MISC_IRQ_AHB_PROC);
152 	if (request_irq(irq, ar5312_ahb_err_handler, 0, "ar5312-ahb-error",
153 			NULL))
154 		pr_err("Failed to register ar5312-ahb-error interrupt\n");
155 
156 	irq_set_chained_handler_and_data(AR5312_IRQ_MISC,
157 					 ar5312_misc_irq_handler, domain);
158 
159 	ar5312_misc_irq_domain = domain;
160 }
161 
162 static struct physmap_flash_data ar5312_flash_data = {
163 	.width = 2,
164 };
165 
166 static struct resource ar5312_flash_resource = {
167 	.start = AR5312_FLASH_BASE,
168 	.end = AR5312_FLASH_BASE + AR5312_FLASH_SIZE - 1,
169 	.flags = IORESOURCE_MEM,
170 };
171 
172 static struct platform_device ar5312_physmap_flash = {
173 	.name = "physmap-flash",
174 	.id = 0,
175 	.dev.platform_data = &ar5312_flash_data,
176 	.resource = &ar5312_flash_resource,
177 	.num_resources = 1,
178 };
179 
180 static void __init ar5312_flash_init(void)
181 {
182 	void __iomem *flashctl_base;
183 	u32 ctl;
184 
185 	flashctl_base = ioremap(AR5312_FLASHCTL_BASE,
186 					AR5312_FLASHCTL_SIZE);
187 
188 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL0);
189 	ctl &= AR5312_FLASHCTL_MW;
190 
191 	/* fixup flash width */
192 	switch (ctl) {
193 	case AR5312_FLASHCTL_MW16:
194 		ar5312_flash_data.width = 2;
195 		break;
196 	case AR5312_FLASHCTL_MW8:
197 	default:
198 		ar5312_flash_data.width = 1;
199 		break;
200 	}
201 
202 	/*
203 	 * Configure flash bank 0.
204 	 * Assume 8M window size. Flash will be aliased if it's smaller
205 	 */
206 	ctl |= AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC_8M | AR5312_FLASHCTL_RBLE;
207 	ctl |= 0x01 << AR5312_FLASHCTL_IDCY_S;
208 	ctl |= 0x07 << AR5312_FLASHCTL_WST1_S;
209 	ctl |= 0x07 << AR5312_FLASHCTL_WST2_S;
210 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL0);
211 
212 	/* Disable other flash banks */
213 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL1);
214 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
215 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL1);
216 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL2);
217 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
218 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL2);
219 
220 	iounmap(flashctl_base);
221 }
222 
223 void __init ar5312_init_devices(void)
224 {
225 	struct ath25_boarddata *config;
226 
227 	ar5312_flash_init();
228 
229 	/* Locate board/radio config data */
230 	ath25_find_config(AR5312_FLASH_BASE, AR5312_FLASH_SIZE);
231 	config = ath25_board.config;
232 
233 	/* AR2313 has CPU minor rev. 10 */
234 	if ((current_cpu_data.processor_id & 0xff) == 0x0a)
235 		ath25_soc = ATH25_SOC_AR2313;
236 
237 	/* AR2312 shares the same Silicon ID as AR5312 */
238 	else if (config->flags & BD_ISCASPER)
239 		ath25_soc = ATH25_SOC_AR2312;
240 
241 	/* Everything else is probably AR5312 or compatible */
242 	else
243 		ath25_soc = ATH25_SOC_AR5312;
244 
245 	platform_device_register(&ar5312_physmap_flash);
246 
247 	switch (ath25_soc) {
248 	case ATH25_SOC_AR5312:
249 		if (!ath25_board.radio)
250 			return;
251 
252 		if (!(config->flags & BD_WLAN0))
253 			break;
254 
255 		ath25_add_wmac(0, AR5312_WLAN0_BASE, AR5312_IRQ_WLAN0);
256 		break;
257 	case ATH25_SOC_AR2312:
258 	case ATH25_SOC_AR2313:
259 		if (!ath25_board.radio)
260 			return;
261 		break;
262 	default:
263 		break;
264 	}
265 
266 	if (config->flags & BD_WLAN1)
267 		ath25_add_wmac(1, AR5312_WLAN1_BASE, AR5312_IRQ_WLAN1);
268 }
269 
270 static void ar5312_restart(char *command)
271 {
272 	/* reset the system */
273 	local_irq_disable();
274 	while (1)
275 		ar5312_rst_reg_write(AR5312_RESET, AR5312_RESET_SYSTEM);
276 }
277 
278 /*
279  * This table is indexed by bits 5..4 of the CLOCKCTL1 register
280  * to determine the predevisor value.
281  */
282 static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
283 
284 static unsigned __init ar5312_cpu_frequency(void)
285 {
286 	u32 scratch, devid, clock_ctl1;
287 	u32 predivide_mask, multiplier_mask, doubler_mask;
288 	unsigned predivide_shift, multiplier_shift;
289 	unsigned predivide_select, predivisor, multiplier;
290 
291 	/* Trust the bootrom's idea of cpu frequency. */
292 	scratch = ar5312_rst_reg_read(AR5312_SCRATCH);
293 	if (scratch)
294 		return scratch;
295 
296 	devid = ar5312_rst_reg_read(AR5312_REV);
297 	devid = (devid & AR5312_REV_MAJ) >> AR5312_REV_MAJ_S;
298 	if (devid == AR5312_REV_MAJ_AR2313) {
299 		predivide_mask = AR2313_CLOCKCTL1_PREDIVIDE_MASK;
300 		predivide_shift = AR2313_CLOCKCTL1_PREDIVIDE_SHIFT;
301 		multiplier_mask = AR2313_CLOCKCTL1_MULTIPLIER_MASK;
302 		multiplier_shift = AR2313_CLOCKCTL1_MULTIPLIER_SHIFT;
303 		doubler_mask = AR2313_CLOCKCTL1_DOUBLER_MASK;
304 	} else { /* AR5312 and AR2312 */
305 		predivide_mask = AR5312_CLOCKCTL1_PREDIVIDE_MASK;
306 		predivide_shift = AR5312_CLOCKCTL1_PREDIVIDE_SHIFT;
307 		multiplier_mask = AR5312_CLOCKCTL1_MULTIPLIER_MASK;
308 		multiplier_shift = AR5312_CLOCKCTL1_MULTIPLIER_SHIFT;
309 		doubler_mask = AR5312_CLOCKCTL1_DOUBLER_MASK;
310 	}
311 
312 	/*
313 	 * Clocking is derived from a fixed 40MHz input clock.
314 	 *
315 	 *  cpu_freq = input_clock * MULT (where MULT is PLL multiplier)
316 	 *  sys_freq = cpu_freq / 4	  (used for APB clock, serial,
317 	 *				   flash, Timer, Watchdog Timer)
318 	 *
319 	 *  cnt_freq = cpu_freq / 2	  (use for CPU count/compare)
320 	 *
321 	 * So, for example, with a PLL multiplier of 5, we have
322 	 *
323 	 *  cpu_freq = 200MHz
324 	 *  sys_freq = 50MHz
325 	 *  cnt_freq = 100MHz
326 	 *
327 	 * We compute the CPU frequency, based on PLL settings.
328 	 */
329 
330 	clock_ctl1 = ar5312_rst_reg_read(AR5312_CLOCKCTL1);
331 	predivide_select = (clock_ctl1 & predivide_mask) >> predivide_shift;
332 	predivisor = clockctl1_predivide_table[predivide_select];
333 	multiplier = (clock_ctl1 & multiplier_mask) >> multiplier_shift;
334 
335 	if (clock_ctl1 & doubler_mask)
336 		multiplier <<= 1;
337 
338 	return (40000000 / predivisor) * multiplier;
339 }
340 
341 static inline unsigned ar5312_sys_frequency(void)
342 {
343 	return ar5312_cpu_frequency() / 4;
344 }
345 
346 void __init ar5312_plat_time_init(void)
347 {
348 	mips_hpt_frequency = ar5312_cpu_frequency() / 2;
349 }
350 
351 void __init ar5312_plat_mem_setup(void)
352 {
353 	void __iomem *sdram_base;
354 	u32 memsize, memcfg, bank0_ac, bank1_ac;
355 	u32 devid;
356 
357 	/* Detect memory size */
358 	sdram_base = ioremap(AR5312_SDRAMCTL_BASE,
359 				     AR5312_SDRAMCTL_SIZE);
360 	memcfg = __raw_readl(sdram_base + AR5312_MEM_CFG1);
361 	bank0_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC0);
362 	bank1_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC1);
363 	memsize = (bank0_ac ? (1 << (bank0_ac + 1)) : 0) +
364 		  (bank1_ac ? (1 << (bank1_ac + 1)) : 0);
365 	memsize <<= 20;
366 	memblock_add(0, memsize);
367 	iounmap(sdram_base);
368 
369 	ar5312_rst_base = ioremap(AR5312_RST_BASE, AR5312_RST_SIZE);
370 
371 	devid = ar5312_rst_reg_read(AR5312_REV);
372 	devid >>= AR5312_REV_WMAC_MIN_S;
373 	devid &= AR5312_REV_CHIP;
374 	ath25_board.devid = (u16)devid;
375 
376 	/* Clear any lingering AHB errors */
377 	ar5312_rst_reg_read(AR5312_PROCADDR);
378 	ar5312_rst_reg_read(AR5312_DMAADDR);
379 	ar5312_rst_reg_write(AR5312_WDT_CTRL, AR5312_WDT_CTRL_IGNORE);
380 
381 	_machine_restart = ar5312_restart;
382 }
383 
384 void __init ar5312_arch_init(void)
385 {
386 	unsigned irq = irq_create_mapping(ar5312_misc_irq_domain,
387 					  AR5312_MISC_IRQ_UART0);
388 
389 	ath25_serial_setup(AR5312_UART0_BASE, irq, ar5312_sys_frequency());
390 }
391