xref: /openbmc/linux/arch/mips/ath25/ar5312.c (revision ae213c44)
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/platform_device.h>
23 #include <linux/mtd/physmap.h>
24 #include <linux/reboot.h>
25 #include <asm/bootinfo.h>
26 #include <asm/reboot.h>
27 #include <asm/time.h>
28 
29 #include <ath25_platform.h>
30 
31 #include "devices.h"
32 #include "ar5312.h"
33 #include "ar5312_regs.h"
34 
35 static void __iomem *ar5312_rst_base;
36 static struct irq_domain *ar5312_misc_irq_domain;
37 
38 static inline u32 ar5312_rst_reg_read(u32 reg)
39 {
40 	return __raw_readl(ar5312_rst_base + reg);
41 }
42 
43 static inline void ar5312_rst_reg_write(u32 reg, u32 val)
44 {
45 	__raw_writel(val, ar5312_rst_base + reg);
46 }
47 
48 static inline void ar5312_rst_reg_mask(u32 reg, u32 mask, u32 val)
49 {
50 	u32 ret = ar5312_rst_reg_read(reg);
51 
52 	ret &= ~mask;
53 	ret |= val;
54 	ar5312_rst_reg_write(reg, ret);
55 }
56 
57 static irqreturn_t ar5312_ahb_err_handler(int cpl, void *dev_id)
58 {
59 	u32 proc1 = ar5312_rst_reg_read(AR5312_PROC1);
60 	u32 proc_addr = ar5312_rst_reg_read(AR5312_PROCADDR); /* clears error */
61 	u32 dma1 = ar5312_rst_reg_read(AR5312_DMA1);
62 	u32 dma_addr = ar5312_rst_reg_read(AR5312_DMAADDR);   /* clears error */
63 
64 	pr_emerg("AHB interrupt: PROCADDR=0x%8.8x PROC1=0x%8.8x DMAADDR=0x%8.8x DMA1=0x%8.8x\n",
65 		 proc_addr, proc1, dma_addr, dma1);
66 
67 	machine_restart("AHB error"); /* Catastrophic failure */
68 	return IRQ_HANDLED;
69 }
70 
71 static struct irqaction ar5312_ahb_err_interrupt  = {
72 	.handler = ar5312_ahb_err_handler,
73 	.name    = "ar5312-ahb-error",
74 };
75 
76 static void ar5312_misc_irq_handler(struct irq_desc *desc)
77 {
78 	u32 pending = ar5312_rst_reg_read(AR5312_ISR) &
79 		      ar5312_rst_reg_read(AR5312_IMR);
80 	unsigned nr, misc_irq = 0;
81 
82 	if (pending) {
83 		struct irq_domain *domain = irq_desc_get_handler_data(desc);
84 
85 		nr = __ffs(pending);
86 		misc_irq = irq_find_mapping(domain, nr);
87 	}
88 
89 	if (misc_irq) {
90 		generic_handle_irq(misc_irq);
91 		if (nr == AR5312_MISC_IRQ_TIMER)
92 			ar5312_rst_reg_read(AR5312_TIMER);
93 	} else {
94 		spurious_interrupt();
95 	}
96 }
97 
98 /* Enable the specified AR5312_MISC_IRQ interrupt */
99 static void ar5312_misc_irq_unmask(struct irq_data *d)
100 {
101 	ar5312_rst_reg_mask(AR5312_IMR, 0, BIT(d->hwirq));
102 }
103 
104 /* Disable the specified AR5312_MISC_IRQ interrupt */
105 static void ar5312_misc_irq_mask(struct irq_data *d)
106 {
107 	ar5312_rst_reg_mask(AR5312_IMR, BIT(d->hwirq), 0);
108 	ar5312_rst_reg_read(AR5312_IMR); /* flush write buffer */
109 }
110 
111 static struct irq_chip ar5312_misc_irq_chip = {
112 	.name		= "ar5312-misc",
113 	.irq_unmask	= ar5312_misc_irq_unmask,
114 	.irq_mask	= ar5312_misc_irq_mask,
115 };
116 
117 static int ar5312_misc_irq_map(struct irq_domain *d, unsigned irq,
118 			       irq_hw_number_t hw)
119 {
120 	irq_set_chip_and_handler(irq, &ar5312_misc_irq_chip, handle_level_irq);
121 	return 0;
122 }
123 
124 static struct irq_domain_ops ar5312_misc_irq_domain_ops = {
125 	.map = ar5312_misc_irq_map,
126 };
127 
128 static void ar5312_irq_dispatch(void)
129 {
130 	u32 pending = read_c0_status() & read_c0_cause();
131 
132 	if (pending & CAUSEF_IP2)
133 		do_IRQ(AR5312_IRQ_WLAN0);
134 	else if (pending & CAUSEF_IP5)
135 		do_IRQ(AR5312_IRQ_WLAN1);
136 	else if (pending & CAUSEF_IP6)
137 		do_IRQ(AR5312_IRQ_MISC);
138 	else if (pending & CAUSEF_IP7)
139 		do_IRQ(ATH25_IRQ_CPU_CLOCK);
140 	else
141 		spurious_interrupt();
142 }
143 
144 void __init ar5312_arch_init_irq(void)
145 {
146 	struct irq_domain *domain;
147 	unsigned irq;
148 
149 	ath25_irq_dispatch = ar5312_irq_dispatch;
150 
151 	domain = irq_domain_add_linear(NULL, AR5312_MISC_IRQ_COUNT,
152 				       &ar5312_misc_irq_domain_ops, NULL);
153 	if (!domain)
154 		panic("Failed to add IRQ domain");
155 
156 	irq = irq_create_mapping(domain, AR5312_MISC_IRQ_AHB_PROC);
157 	setup_irq(irq, &ar5312_ahb_err_interrupt);
158 
159 	irq_set_chained_handler_and_data(AR5312_IRQ_MISC,
160 					 ar5312_misc_irq_handler, domain);
161 
162 	ar5312_misc_irq_domain = domain;
163 }
164 
165 static struct physmap_flash_data ar5312_flash_data = {
166 	.width = 2,
167 };
168 
169 static struct resource ar5312_flash_resource = {
170 	.start = AR5312_FLASH_BASE,
171 	.end = AR5312_FLASH_BASE + AR5312_FLASH_SIZE - 1,
172 	.flags = IORESOURCE_MEM,
173 };
174 
175 static struct platform_device ar5312_physmap_flash = {
176 	.name = "physmap-flash",
177 	.id = 0,
178 	.dev.platform_data = &ar5312_flash_data,
179 	.resource = &ar5312_flash_resource,
180 	.num_resources = 1,
181 };
182 
183 static void __init ar5312_flash_init(void)
184 {
185 	void __iomem *flashctl_base;
186 	u32 ctl;
187 
188 	flashctl_base = ioremap_nocache(AR5312_FLASHCTL_BASE,
189 					AR5312_FLASHCTL_SIZE);
190 
191 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL0);
192 	ctl &= AR5312_FLASHCTL_MW;
193 
194 	/* fixup flash width */
195 	switch (ctl) {
196 	case AR5312_FLASHCTL_MW16:
197 		ar5312_flash_data.width = 2;
198 		break;
199 	case AR5312_FLASHCTL_MW8:
200 	default:
201 		ar5312_flash_data.width = 1;
202 		break;
203 	}
204 
205 	/*
206 	 * Configure flash bank 0.
207 	 * Assume 8M window size. Flash will be aliased if it's smaller
208 	 */
209 	ctl |= AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC_8M | AR5312_FLASHCTL_RBLE;
210 	ctl |= 0x01 << AR5312_FLASHCTL_IDCY_S;
211 	ctl |= 0x07 << AR5312_FLASHCTL_WST1_S;
212 	ctl |= 0x07 << AR5312_FLASHCTL_WST2_S;
213 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL0);
214 
215 	/* Disable other flash banks */
216 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL1);
217 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
218 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL1);
219 	ctl = __raw_readl(flashctl_base + AR5312_FLASHCTL2);
220 	ctl &= ~(AR5312_FLASHCTL_E | AR5312_FLASHCTL_AC);
221 	__raw_writel(ctl, flashctl_base + AR5312_FLASHCTL2);
222 
223 	iounmap(flashctl_base);
224 }
225 
226 void __init ar5312_init_devices(void)
227 {
228 	struct ath25_boarddata *config;
229 
230 	ar5312_flash_init();
231 
232 	/* Locate board/radio config data */
233 	ath25_find_config(AR5312_FLASH_BASE, AR5312_FLASH_SIZE);
234 	config = ath25_board.config;
235 
236 	/* AR2313 has CPU minor rev. 10 */
237 	if ((current_cpu_data.processor_id & 0xff) == 0x0a)
238 		ath25_soc = ATH25_SOC_AR2313;
239 
240 	/* AR2312 shares the same Silicon ID as AR5312 */
241 	else if (config->flags & BD_ISCASPER)
242 		ath25_soc = ATH25_SOC_AR2312;
243 
244 	/* Everything else is probably AR5312 or compatible */
245 	else
246 		ath25_soc = ATH25_SOC_AR5312;
247 
248 	platform_device_register(&ar5312_physmap_flash);
249 
250 	switch (ath25_soc) {
251 	case ATH25_SOC_AR5312:
252 		if (!ath25_board.radio)
253 			return;
254 
255 		if (!(config->flags & BD_WLAN0))
256 			break;
257 
258 		ath25_add_wmac(0, AR5312_WLAN0_BASE, AR5312_IRQ_WLAN0);
259 		break;
260 	case ATH25_SOC_AR2312:
261 	case ATH25_SOC_AR2313:
262 		if (!ath25_board.radio)
263 			return;
264 		break;
265 	default:
266 		break;
267 	}
268 
269 	if (config->flags & BD_WLAN1)
270 		ath25_add_wmac(1, AR5312_WLAN1_BASE, AR5312_IRQ_WLAN1);
271 }
272 
273 static void ar5312_restart(char *command)
274 {
275 	/* reset the system */
276 	local_irq_disable();
277 	while (1)
278 		ar5312_rst_reg_write(AR5312_RESET, AR5312_RESET_SYSTEM);
279 }
280 
281 /*
282  * This table is indexed by bits 5..4 of the CLOCKCTL1 register
283  * to determine the predevisor value.
284  */
285 static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
286 
287 static unsigned __init ar5312_cpu_frequency(void)
288 {
289 	u32 scratch, devid, clock_ctl1;
290 	u32 predivide_mask, multiplier_mask, doubler_mask;
291 	unsigned predivide_shift, multiplier_shift;
292 	unsigned predivide_select, predivisor, multiplier;
293 
294 	/* Trust the bootrom's idea of cpu frequency. */
295 	scratch = ar5312_rst_reg_read(AR5312_SCRATCH);
296 	if (scratch)
297 		return scratch;
298 
299 	devid = ar5312_rst_reg_read(AR5312_REV);
300 	devid = (devid & AR5312_REV_MAJ) >> AR5312_REV_MAJ_S;
301 	if (devid == AR5312_REV_MAJ_AR2313) {
302 		predivide_mask = AR2313_CLOCKCTL1_PREDIVIDE_MASK;
303 		predivide_shift = AR2313_CLOCKCTL1_PREDIVIDE_SHIFT;
304 		multiplier_mask = AR2313_CLOCKCTL1_MULTIPLIER_MASK;
305 		multiplier_shift = AR2313_CLOCKCTL1_MULTIPLIER_SHIFT;
306 		doubler_mask = AR2313_CLOCKCTL1_DOUBLER_MASK;
307 	} else { /* AR5312 and AR2312 */
308 		predivide_mask = AR5312_CLOCKCTL1_PREDIVIDE_MASK;
309 		predivide_shift = AR5312_CLOCKCTL1_PREDIVIDE_SHIFT;
310 		multiplier_mask = AR5312_CLOCKCTL1_MULTIPLIER_MASK;
311 		multiplier_shift = AR5312_CLOCKCTL1_MULTIPLIER_SHIFT;
312 		doubler_mask = AR5312_CLOCKCTL1_DOUBLER_MASK;
313 	}
314 
315 	/*
316 	 * Clocking is derived from a fixed 40MHz input clock.
317 	 *
318 	 *  cpu_freq = input_clock * MULT (where MULT is PLL multiplier)
319 	 *  sys_freq = cpu_freq / 4	  (used for APB clock, serial,
320 	 *				   flash, Timer, Watchdog Timer)
321 	 *
322 	 *  cnt_freq = cpu_freq / 2	  (use for CPU count/compare)
323 	 *
324 	 * So, for example, with a PLL multiplier of 5, we have
325 	 *
326 	 *  cpu_freq = 200MHz
327 	 *  sys_freq = 50MHz
328 	 *  cnt_freq = 100MHz
329 	 *
330 	 * We compute the CPU frequency, based on PLL settings.
331 	 */
332 
333 	clock_ctl1 = ar5312_rst_reg_read(AR5312_CLOCKCTL1);
334 	predivide_select = (clock_ctl1 & predivide_mask) >> predivide_shift;
335 	predivisor = clockctl1_predivide_table[predivide_select];
336 	multiplier = (clock_ctl1 & multiplier_mask) >> multiplier_shift;
337 
338 	if (clock_ctl1 & doubler_mask)
339 		multiplier <<= 1;
340 
341 	return (40000000 / predivisor) * multiplier;
342 }
343 
344 static inline unsigned ar5312_sys_frequency(void)
345 {
346 	return ar5312_cpu_frequency() / 4;
347 }
348 
349 void __init ar5312_plat_time_init(void)
350 {
351 	mips_hpt_frequency = ar5312_cpu_frequency() / 2;
352 }
353 
354 void __init ar5312_plat_mem_setup(void)
355 {
356 	void __iomem *sdram_base;
357 	u32 memsize, memcfg, bank0_ac, bank1_ac;
358 	u32 devid;
359 
360 	/* Detect memory size */
361 	sdram_base = ioremap_nocache(AR5312_SDRAMCTL_BASE,
362 				     AR5312_SDRAMCTL_SIZE);
363 	memcfg = __raw_readl(sdram_base + AR5312_MEM_CFG1);
364 	bank0_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC0);
365 	bank1_ac = ATH25_REG_MS(memcfg, AR5312_MEM_CFG1_AC1);
366 	memsize = (bank0_ac ? (1 << (bank0_ac + 1)) : 0) +
367 		  (bank1_ac ? (1 << (bank1_ac + 1)) : 0);
368 	memsize <<= 20;
369 	add_memory_region(0, memsize, BOOT_MEM_RAM);
370 	iounmap(sdram_base);
371 
372 	ar5312_rst_base = ioremap_nocache(AR5312_RST_BASE, AR5312_RST_SIZE);
373 
374 	devid = ar5312_rst_reg_read(AR5312_REV);
375 	devid >>= AR5312_REV_WMAC_MIN_S;
376 	devid &= AR5312_REV_CHIP;
377 	ath25_board.devid = (u16)devid;
378 
379 	/* Clear any lingering AHB errors */
380 	ar5312_rst_reg_read(AR5312_PROCADDR);
381 	ar5312_rst_reg_read(AR5312_DMAADDR);
382 	ar5312_rst_reg_write(AR5312_WDT_CTRL, AR5312_WDT_CTRL_IGNORE);
383 
384 	_machine_restart = ar5312_restart;
385 }
386 
387 void __init ar5312_arch_init(void)
388 {
389 	unsigned irq = irq_create_mapping(ar5312_misc_irq_domain,
390 					  AR5312_MISC_IRQ_UART0);
391 
392 	ath25_serial_setup(AR5312_UART0_BASE, irq, ar5312_sys_frequency());
393 }
394