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 Felix Fietkau <nbd@openwrt.org> 10 * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com> 11 */ 12 13 /* 14 * Platform devices for Atheros AR2315 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/reboot.h> 24 #include <asm/bootinfo.h> 25 #include <asm/reboot.h> 26 #include <asm/time.h> 27 28 #include <ath25_platform.h> 29 30 #include "devices.h" 31 #include "ar2315.h" 32 #include "ar2315_regs.h" 33 34 static void __iomem *ar2315_rst_base; 35 static struct irq_domain *ar2315_misc_irq_domain; 36 37 static inline u32 ar2315_rst_reg_read(u32 reg) 38 { 39 return __raw_readl(ar2315_rst_base + reg); 40 } 41 42 static inline void ar2315_rst_reg_write(u32 reg, u32 val) 43 { 44 __raw_writel(val, ar2315_rst_base + reg); 45 } 46 47 static inline void ar2315_rst_reg_mask(u32 reg, u32 mask, u32 val) 48 { 49 u32 ret = ar2315_rst_reg_read(reg); 50 51 ret &= ~mask; 52 ret |= val; 53 ar2315_rst_reg_write(reg, ret); 54 } 55 56 static irqreturn_t ar2315_ahb_err_handler(int cpl, void *dev_id) 57 { 58 ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET); 59 ar2315_rst_reg_read(AR2315_AHB_ERR1); 60 61 pr_emerg("AHB fatal error\n"); 62 machine_restart("AHB error"); /* Catastrophic failure */ 63 64 return IRQ_HANDLED; 65 } 66 67 static struct irqaction ar2315_ahb_err_interrupt = { 68 .handler = ar2315_ahb_err_handler, 69 .name = "ar2315-ahb-error", 70 }; 71 72 static void ar2315_misc_irq_handler(struct irq_desc *desc) 73 { 74 u32 pending = ar2315_rst_reg_read(AR2315_ISR) & 75 ar2315_rst_reg_read(AR2315_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 if (nr == AR2315_MISC_IRQ_GPIO) 87 ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_GPIO); 88 else if (nr == AR2315_MISC_IRQ_WATCHDOG) 89 ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_WD); 90 generic_handle_irq(misc_irq); 91 } else { 92 spurious_interrupt(); 93 } 94 } 95 96 static void ar2315_misc_irq_unmask(struct irq_data *d) 97 { 98 ar2315_rst_reg_mask(AR2315_IMR, 0, BIT(d->hwirq)); 99 } 100 101 static void ar2315_misc_irq_mask(struct irq_data *d) 102 { 103 ar2315_rst_reg_mask(AR2315_IMR, BIT(d->hwirq), 0); 104 } 105 106 static struct irq_chip ar2315_misc_irq_chip = { 107 .name = "ar2315-misc", 108 .irq_unmask = ar2315_misc_irq_unmask, 109 .irq_mask = ar2315_misc_irq_mask, 110 }; 111 112 static int ar2315_misc_irq_map(struct irq_domain *d, unsigned irq, 113 irq_hw_number_t hw) 114 { 115 irq_set_chip_and_handler(irq, &ar2315_misc_irq_chip, handle_level_irq); 116 return 0; 117 } 118 119 static struct irq_domain_ops ar2315_misc_irq_domain_ops = { 120 .map = ar2315_misc_irq_map, 121 }; 122 123 /* 124 * Called when an interrupt is received, this function 125 * determines exactly which interrupt it was, and it 126 * invokes the appropriate handler. 127 * 128 * Implicitly, we also define interrupt priority by 129 * choosing which to dispatch first. 130 */ 131 static void ar2315_irq_dispatch(void) 132 { 133 u32 pending = read_c0_status() & read_c0_cause(); 134 135 if (pending & CAUSEF_IP3) 136 do_IRQ(AR2315_IRQ_WLAN0); 137 #ifdef CONFIG_PCI_AR2315 138 else if (pending & CAUSEF_IP5) 139 do_IRQ(AR2315_IRQ_LCBUS_PCI); 140 #endif 141 else if (pending & CAUSEF_IP2) 142 do_IRQ(AR2315_IRQ_MISC); 143 else if (pending & CAUSEF_IP7) 144 do_IRQ(ATH25_IRQ_CPU_CLOCK); 145 else 146 spurious_interrupt(); 147 } 148 149 void __init ar2315_arch_init_irq(void) 150 { 151 struct irq_domain *domain; 152 unsigned irq; 153 154 ath25_irq_dispatch = ar2315_irq_dispatch; 155 156 domain = irq_domain_add_linear(NULL, AR2315_MISC_IRQ_COUNT, 157 &ar2315_misc_irq_domain_ops, NULL); 158 if (!domain) 159 panic("Failed to add IRQ domain"); 160 161 irq = irq_create_mapping(domain, AR2315_MISC_IRQ_AHB); 162 setup_irq(irq, &ar2315_ahb_err_interrupt); 163 164 irq_set_chained_handler_and_data(AR2315_IRQ_MISC, 165 ar2315_misc_irq_handler, domain); 166 167 ar2315_misc_irq_domain = domain; 168 } 169 170 void __init ar2315_init_devices(void) 171 { 172 /* Find board configuration */ 173 ath25_find_config(AR2315_SPI_READ_BASE, AR2315_SPI_READ_SIZE); 174 175 ath25_add_wmac(0, AR2315_WLAN0_BASE, AR2315_IRQ_WLAN0); 176 } 177 178 static void ar2315_restart(char *command) 179 { 180 void (*mips_reset_vec)(void) = (void *)0xbfc00000; 181 182 local_irq_disable(); 183 184 /* try reset the system via reset control */ 185 ar2315_rst_reg_write(AR2315_COLD_RESET, AR2317_RESET_SYSTEM); 186 187 /* Cold reset does not work on the AR2315/6, use the GPIO reset bits 188 * a workaround. Give it some time to attempt a gpio based hardware 189 * reset (atheros reference design workaround) */ 190 191 /* TODO: implement the GPIO reset workaround */ 192 193 /* Some boards (e.g. Senao EOC-2610) don't implement the reset logic 194 * workaround. Attempt to jump to the mips reset location - 195 * the boot loader itself might be able to recover the system */ 196 mips_reset_vec(); 197 } 198 199 /* 200 * This table is indexed by bits 5..4 of the CLOCKCTL1 register 201 * to determine the predevisor value. 202 */ 203 static int clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 }; 204 static int pllc_divide_table[5] __initdata = { 2, 3, 4, 6, 3 }; 205 206 static unsigned __init ar2315_sys_clk(u32 clock_ctl) 207 { 208 unsigned int pllc_ctrl, cpu_div; 209 unsigned int pllc_out, refdiv, fdiv, divby2; 210 unsigned int clk_div; 211 212 pllc_ctrl = ar2315_rst_reg_read(AR2315_PLLC_CTL); 213 refdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_REF_DIV); 214 refdiv = clockctl1_predivide_table[refdiv]; 215 fdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_FDBACK_DIV); 216 divby2 = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_ADD_FDBACK_DIV) + 1; 217 pllc_out = (40000000 / refdiv) * (2 * divby2) * fdiv; 218 219 /* clkm input selected */ 220 switch (clock_ctl & AR2315_CPUCLK_CLK_SEL_M) { 221 case 0: 222 case 1: 223 clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKM_DIV); 224 clk_div = pllc_divide_table[clk_div]; 225 break; 226 case 2: 227 clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKC_DIV); 228 clk_div = pllc_divide_table[clk_div]; 229 break; 230 default: 231 pllc_out = 40000000; 232 clk_div = 1; 233 break; 234 } 235 236 cpu_div = ATH25_REG_MS(clock_ctl, AR2315_CPUCLK_CLK_DIV); 237 cpu_div = cpu_div * 2 ?: 1; 238 239 return pllc_out / (clk_div * cpu_div); 240 } 241 242 static inline unsigned ar2315_cpu_frequency(void) 243 { 244 return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_CPUCLK)); 245 } 246 247 static inline unsigned ar2315_apb_frequency(void) 248 { 249 return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_AMBACLK)); 250 } 251 252 void __init ar2315_plat_time_init(void) 253 { 254 mips_hpt_frequency = ar2315_cpu_frequency() / 2; 255 } 256 257 void __init ar2315_plat_mem_setup(void) 258 { 259 void __iomem *sdram_base; 260 u32 memsize, memcfg; 261 u32 devid; 262 u32 config; 263 264 /* Detect memory size */ 265 sdram_base = ioremap(AR2315_SDRAMCTL_BASE, 266 AR2315_SDRAMCTL_SIZE); 267 memcfg = __raw_readl(sdram_base + AR2315_MEM_CFG); 268 memsize = 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_DATA_WIDTH); 269 memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_COL_WIDTH); 270 memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_ROW_WIDTH); 271 memsize <<= 3; 272 add_memory_region(0, memsize, BOOT_MEM_RAM); 273 iounmap(sdram_base); 274 275 ar2315_rst_base = ioremap(AR2315_RST_BASE, AR2315_RST_SIZE); 276 277 /* Detect the hardware based on the device ID */ 278 devid = ar2315_rst_reg_read(AR2315_SREV) & AR2315_REV_CHIP; 279 switch (devid) { 280 case 0x91: /* Need to check */ 281 ath25_soc = ATH25_SOC_AR2318; 282 break; 283 case 0x90: 284 ath25_soc = ATH25_SOC_AR2317; 285 break; 286 case 0x87: 287 ath25_soc = ATH25_SOC_AR2316; 288 break; 289 case 0x86: 290 default: 291 ath25_soc = ATH25_SOC_AR2315; 292 break; 293 } 294 ath25_board.devid = devid; 295 296 /* Clear any lingering AHB errors */ 297 config = read_c0_config(); 298 write_c0_config(config & ~0x3); 299 ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET); 300 ar2315_rst_reg_read(AR2315_AHB_ERR1); 301 ar2315_rst_reg_write(AR2315_WDT_CTRL, AR2315_WDT_CTRL_IGNORE); 302 303 _machine_restart = ar2315_restart; 304 } 305 306 #ifdef CONFIG_PCI_AR2315 307 static struct resource ar2315_pci_res[] = { 308 { 309 .name = "ar2315-pci-ctrl", 310 .flags = IORESOURCE_MEM, 311 .start = AR2315_PCI_BASE, 312 .end = AR2315_PCI_BASE + AR2315_PCI_SIZE - 1, 313 }, 314 { 315 .name = "ar2315-pci-ext", 316 .flags = IORESOURCE_MEM, 317 .start = AR2315_PCI_EXT_BASE, 318 .end = AR2315_PCI_EXT_BASE + AR2315_PCI_EXT_SIZE - 1, 319 }, 320 { 321 .name = "ar2315-pci", 322 .flags = IORESOURCE_IRQ, 323 .start = AR2315_IRQ_LCBUS_PCI, 324 .end = AR2315_IRQ_LCBUS_PCI, 325 }, 326 }; 327 #endif 328 329 void __init ar2315_arch_init(void) 330 { 331 unsigned irq = irq_create_mapping(ar2315_misc_irq_domain, 332 AR2315_MISC_IRQ_UART0); 333 334 ath25_serial_setup(AR2315_UART0_BASE, irq, ar2315_apb_frequency()); 335 336 #ifdef CONFIG_PCI_AR2315 337 if (ath25_soc == ATH25_SOC_AR2315) { 338 /* Reset PCI DMA logic */ 339 ar2315_rst_reg_mask(AR2315_RESET, 0, AR2315_RESET_PCIDMA); 340 msleep(20); 341 ar2315_rst_reg_mask(AR2315_RESET, AR2315_RESET_PCIDMA, 0); 342 msleep(20); 343 344 /* Configure endians */ 345 ar2315_rst_reg_mask(AR2315_ENDIAN_CTL, 0, AR2315_CONFIG_PCIAHB | 346 AR2315_CONFIG_PCIAHB_BRIDGE); 347 348 /* Configure as PCI host with DMA */ 349 ar2315_rst_reg_write(AR2315_PCICLK, AR2315_PCICLK_PLLC_CLKM | 350 (AR2315_PCICLK_IN_FREQ_DIV_6 << 351 AR2315_PCICLK_DIV_S)); 352 ar2315_rst_reg_mask(AR2315_AHB_ARB_CTL, 0, AR2315_ARB_PCI); 353 ar2315_rst_reg_mask(AR2315_IF_CTL, AR2315_IF_PCI_CLK_MASK | 354 AR2315_IF_MASK, AR2315_IF_PCI | 355 AR2315_IF_PCI_HOST | AR2315_IF_PCI_INTR | 356 (AR2315_IF_PCI_CLK_OUTPUT_CLK << 357 AR2315_IF_PCI_CLK_SHIFT)); 358 359 platform_device_register_simple("ar2315-pci", -1, 360 ar2315_pci_res, 361 ARRAY_SIZE(ar2315_pci_res)); 362 } 363 #endif 364 } 365