linux/arch/mips/ath25/ar5312.c
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   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
  35static void __iomem *ar5312_rst_base;
  36static struct irq_domain *ar5312_misc_irq_domain;
  37
  38static inline u32 ar5312_rst_reg_read(u32 reg)
  39{
  40        return __raw_readl(ar5312_rst_base + reg);
  41}
  42
  43static inline void ar5312_rst_reg_write(u32 reg, u32 val)
  44{
  45        __raw_writel(val, ar5312_rst_base + reg);
  46}
  47
  48static 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
  57static 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
  71static struct irqaction ar5312_ahb_err_interrupt  = {
  72        .handler = ar5312_ahb_err_handler,
  73        .name    = "ar5312-ahb-error",
  74};
  75
  76static 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 */
  99static 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 */
 105static 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
 111static 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
 117static 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
 124static struct irq_domain_ops ar5312_misc_irq_domain_ops = {
 125        .map = ar5312_misc_irq_map,
 126};
 127
 128static 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
 144void __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
 165static struct physmap_flash_data ar5312_flash_data = {
 166        .width = 2,
 167};
 168
 169static 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
 175static 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
 183static 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
 226void __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
 273static 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 */
 285static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
 286
 287static 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
 344static inline unsigned ar5312_sys_frequency(void)
 345{
 346        return ar5312_cpu_frequency() / 4;
 347}
 348
 349void __init ar5312_plat_time_init(void)
 350{
 351        mips_hpt_frequency = ar5312_cpu_frequency() / 2;
 352}
 353
 354void __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
 387void __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