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/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
  36static void __iomem *ar5312_rst_base;
  37static struct irq_domain *ar5312_misc_irq_domain;
  38
  39static inline u32 ar5312_rst_reg_read(u32 reg)
  40{
  41        return __raw_readl(ar5312_rst_base + reg);
  42}
  43
  44static inline void ar5312_rst_reg_write(u32 reg, u32 val)
  45{
  46        __raw_writel(val, ar5312_rst_base + reg);
  47}
  48
  49static 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
  58static 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
  72static 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 */
  94static 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 */
 100static 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
 106static 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
 112static 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
 119static struct irq_domain_ops ar5312_misc_irq_domain_ops = {
 120        .map = ar5312_misc_irq_map,
 121};
 122
 123static 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
 139void __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
 162static struct physmap_flash_data ar5312_flash_data = {
 163        .width = 2,
 164};
 165
 166static 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
 172static 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
 180static 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
 223void __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
 270static 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 */
 282static unsigned clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 };
 283
 284static 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
 341static inline unsigned ar5312_sys_frequency(void)
 342{
 343        return ar5312_cpu_frequency() / 4;
 344}
 345
 346void __init ar5312_plat_time_init(void)
 347{
 348        mips_hpt_frequency = ar5312_cpu_frequency() / 2;
 349}
 350
 351void __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
 384void __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