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/memblock.h> 23 #include <linux/platform_device.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 "ar2315.h" 33 #include "ar2315_regs.h" 34 35 static void __iomem *ar2315_rst_base; 36 static struct irq_domain *ar2315_misc_irq_domain; 37 38 static inline u32 ar2315_rst_reg_read(u32 reg) 39 { 40 return __raw_readl(ar2315_rst_base + reg); 41 } 42 43 static inline void ar2315_rst_reg_write(u32 reg, u32 val) 44 { 45 __raw_writel(val, ar2315_rst_base + reg); 46 } 47 48 static inline void ar2315_rst_reg_mask(u32 reg, u32 mask, u32 val) 49 { 50 u32 ret = ar2315_rst_reg_read(reg); 51 52 ret &= ~mask; 53 ret |= val; 54 ar2315_rst_reg_write(reg, ret); 55 } 56 57 static irqreturn_t ar2315_ahb_err_handler(int cpl, void *dev_id) 58 { 59 ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET); 60 ar2315_rst_reg_read(AR2315_AHB_ERR1); 61 62 pr_emerg("AHB fatal error\n"); 63 machine_restart("AHB error"); /* Catastrophic failure */ 64 65 return IRQ_HANDLED; 66 } 67 68 static void ar2315_misc_irq_handler(struct irq_desc *desc) 69 { 70 u32 pending = ar2315_rst_reg_read(AR2315_ISR) & 71 ar2315_rst_reg_read(AR2315_IMR); 72 unsigned nr; 73 int ret = 0; 74 75 if (pending) { 76 struct irq_domain *domain = irq_desc_get_handler_data(desc); 77 78 nr = __ffs(pending); 79 80 if (nr == AR2315_MISC_IRQ_GPIO) 81 ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_GPIO); 82 else if (nr == AR2315_MISC_IRQ_WATCHDOG) 83 ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_WD); 84 85 ret = generic_handle_domain_irq(domain, nr); 86 } 87 88 if (!pending || ret) 89 spurious_interrupt(); 90 } 91 92 static void ar2315_misc_irq_unmask(struct irq_data *d) 93 { 94 ar2315_rst_reg_mask(AR2315_IMR, 0, BIT(d->hwirq)); 95 } 96 97 static void ar2315_misc_irq_mask(struct irq_data *d) 98 { 99 ar2315_rst_reg_mask(AR2315_IMR, BIT(d->hwirq), 0); 100 } 101 102 static struct irq_chip ar2315_misc_irq_chip = { 103 .name = "ar2315-misc", 104 .irq_unmask = ar2315_misc_irq_unmask, 105 .irq_mask = ar2315_misc_irq_mask, 106 }; 107 108 static int ar2315_misc_irq_map(struct irq_domain *d, unsigned irq, 109 irq_hw_number_t hw) 110 { 111 irq_set_chip_and_handler(irq, &ar2315_misc_irq_chip, handle_level_irq); 112 return 0; 113 } 114 115 static struct irq_domain_ops ar2315_misc_irq_domain_ops = { 116 .map = ar2315_misc_irq_map, 117 }; 118 119 /* 120 * Called when an interrupt is received, this function 121 * determines exactly which interrupt it was, and it 122 * invokes the appropriate handler. 123 * 124 * Implicitly, we also define interrupt priority by 125 * choosing which to dispatch first. 126 */ 127 static void ar2315_irq_dispatch(void) 128 { 129 u32 pending = read_c0_status() & read_c0_cause(); 130 131 if (pending & CAUSEF_IP3) 132 do_IRQ(AR2315_IRQ_WLAN0); 133 #ifdef CONFIG_PCI_AR2315 134 else if (pending & CAUSEF_IP5) 135 do_IRQ(AR2315_IRQ_LCBUS_PCI); 136 #endif 137 else if (pending & CAUSEF_IP2) 138 do_IRQ(AR2315_IRQ_MISC); 139 else if (pending & CAUSEF_IP7) 140 do_IRQ(ATH25_IRQ_CPU_CLOCK); 141 else 142 spurious_interrupt(); 143 } 144 145 void __init ar2315_arch_init_irq(void) 146 { 147 struct irq_domain *domain; 148 unsigned irq; 149 150 ath25_irq_dispatch = ar2315_irq_dispatch; 151 152 domain = irq_domain_add_linear(NULL, AR2315_MISC_IRQ_COUNT, 153 &ar2315_misc_irq_domain_ops, NULL); 154 if (!domain) 155 panic("Failed to add IRQ domain"); 156 157 irq = irq_create_mapping(domain, AR2315_MISC_IRQ_AHB); 158 if (request_irq(irq, ar2315_ahb_err_handler, 0, "ar2315-ahb-error", 159 NULL)) 160 pr_err("Failed to register ar2315-ahb-error interrupt\n"); 161 162 irq_set_chained_handler_and_data(AR2315_IRQ_MISC, 163 ar2315_misc_irq_handler, domain); 164 165 ar2315_misc_irq_domain = domain; 166 } 167 168 void __init ar2315_init_devices(void) 169 { 170 /* Find board configuration */ 171 ath25_find_config(AR2315_SPI_READ_BASE, AR2315_SPI_READ_SIZE); 172 173 ath25_add_wmac(0, AR2315_WLAN0_BASE, AR2315_IRQ_WLAN0); 174 } 175 176 static void ar2315_restart(char *command) 177 { 178 void (*mips_reset_vec)(void) = (void *)0xbfc00000; 179 180 local_irq_disable(); 181 182 /* try reset the system via reset control */ 183 ar2315_rst_reg_write(AR2315_COLD_RESET, AR2317_RESET_SYSTEM); 184 185 /* Cold reset does not work on the AR2315/6, use the GPIO reset bits 186 * a workaround. Give it some time to attempt a gpio based hardware 187 * reset (atheros reference design workaround) */ 188 189 /* TODO: implement the GPIO reset workaround */ 190 191 /* Some boards (e.g. Senao EOC-2610) don't implement the reset logic 192 * workaround. Attempt to jump to the mips reset location - 193 * the boot loader itself might be able to recover the system */ 194 mips_reset_vec(); 195 } 196 197 /* 198 * This table is indexed by bits 5..4 of the CLOCKCTL1 register 199 * to determine the predevisor value. 200 */ 201 static int clockctl1_predivide_table[4] __initdata = { 1, 2, 4, 5 }; 202 static int pllc_divide_table[5] __initdata = { 2, 3, 4, 6, 3 }; 203 204 static unsigned __init ar2315_sys_clk(u32 clock_ctl) 205 { 206 unsigned int pllc_ctrl, cpu_div; 207 unsigned int pllc_out, refdiv, fdiv, divby2; 208 unsigned int clk_div; 209 210 pllc_ctrl = ar2315_rst_reg_read(AR2315_PLLC_CTL); 211 refdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_REF_DIV); 212 refdiv = clockctl1_predivide_table[refdiv]; 213 fdiv = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_FDBACK_DIV); 214 divby2 = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_ADD_FDBACK_DIV) + 1; 215 pllc_out = (40000000 / refdiv) * (2 * divby2) * fdiv; 216 217 /* clkm input selected */ 218 switch (clock_ctl & AR2315_CPUCLK_CLK_SEL_M) { 219 case 0: 220 case 1: 221 clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKM_DIV); 222 clk_div = pllc_divide_table[clk_div]; 223 break; 224 case 2: 225 clk_div = ATH25_REG_MS(pllc_ctrl, AR2315_PLLC_CLKC_DIV); 226 clk_div = pllc_divide_table[clk_div]; 227 break; 228 default: 229 pllc_out = 40000000; 230 clk_div = 1; 231 break; 232 } 233 234 cpu_div = ATH25_REG_MS(clock_ctl, AR2315_CPUCLK_CLK_DIV); 235 cpu_div = cpu_div * 2 ?: 1; 236 237 return pllc_out / (clk_div * cpu_div); 238 } 239 240 static inline unsigned ar2315_cpu_frequency(void) 241 { 242 return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_CPUCLK)); 243 } 244 245 static inline unsigned ar2315_apb_frequency(void) 246 { 247 return ar2315_sys_clk(ar2315_rst_reg_read(AR2315_AMBACLK)); 248 } 249 250 void __init ar2315_plat_time_init(void) 251 { 252 mips_hpt_frequency = ar2315_cpu_frequency() / 2; 253 } 254 255 void __init ar2315_plat_mem_setup(void) 256 { 257 void __iomem *sdram_base; 258 u32 memsize, memcfg; 259 u32 devid; 260 u32 config; 261 262 /* Detect memory size */ 263 sdram_base = ioremap(AR2315_SDRAMCTL_BASE, 264 AR2315_SDRAMCTL_SIZE); 265 memcfg = __raw_readl(sdram_base + AR2315_MEM_CFG); 266 memsize = 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_DATA_WIDTH); 267 memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_COL_WIDTH); 268 memsize <<= 1 + ATH25_REG_MS(memcfg, AR2315_MEM_CFG_ROW_WIDTH); 269 memsize <<= 3; 270 memblock_add(0, memsize); 271 iounmap(sdram_base); 272 273 ar2315_rst_base = ioremap(AR2315_RST_BASE, AR2315_RST_SIZE); 274 275 /* Detect the hardware based on the device ID */ 276 devid = ar2315_rst_reg_read(AR2315_SREV) & AR2315_REV_CHIP; 277 switch (devid) { 278 case 0x91: /* Need to check */ 279 ath25_soc = ATH25_SOC_AR2318; 280 break; 281 case 0x90: 282 ath25_soc = ATH25_SOC_AR2317; 283 break; 284 case 0x87: 285 ath25_soc = ATH25_SOC_AR2316; 286 break; 287 case 0x86: 288 default: 289 ath25_soc = ATH25_SOC_AR2315; 290 break; 291 } 292 ath25_board.devid = devid; 293 294 /* Clear any lingering AHB errors */ 295 config = read_c0_config(); 296 write_c0_config(config & ~0x3); 297 ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET); 298 ar2315_rst_reg_read(AR2315_AHB_ERR1); 299 ar2315_rst_reg_write(AR2315_WDT_CTRL, AR2315_WDT_CTRL_IGNORE); 300 301 _machine_restart = ar2315_restart; 302 } 303 304 #ifdef CONFIG_PCI_AR2315 305 static struct resource ar2315_pci_res[] = { 306 { 307 .name = "ar2315-pci-ctrl", 308 .flags = IORESOURCE_MEM, 309 .start = AR2315_PCI_BASE, 310 .end = AR2315_PCI_BASE + AR2315_PCI_SIZE - 1, 311 }, 312 { 313 .name = "ar2315-pci-ext", 314 .flags = IORESOURCE_MEM, 315 .start = AR2315_PCI_EXT_BASE, 316 .end = AR2315_PCI_EXT_BASE + AR2315_PCI_EXT_SIZE - 1, 317 }, 318 { 319 .name = "ar2315-pci", 320 .flags = IORESOURCE_IRQ, 321 .start = AR2315_IRQ_LCBUS_PCI, 322 .end = AR2315_IRQ_LCBUS_PCI, 323 }, 324 }; 325 #endif 326 327 void __init ar2315_arch_init(void) 328 { 329 unsigned irq = irq_create_mapping(ar2315_misc_irq_domain, 330 AR2315_MISC_IRQ_UART0); 331 332 ath25_serial_setup(AR2315_UART0_BASE, irq, ar2315_apb_frequency()); 333 334 #ifdef CONFIG_PCI_AR2315 335 if (ath25_soc == ATH25_SOC_AR2315) { 336 /* Reset PCI DMA logic */ 337 ar2315_rst_reg_mask(AR2315_RESET, 0, AR2315_RESET_PCIDMA); 338 msleep(20); 339 ar2315_rst_reg_mask(AR2315_RESET, AR2315_RESET_PCIDMA, 0); 340 msleep(20); 341 342 /* Configure endians */ 343 ar2315_rst_reg_mask(AR2315_ENDIAN_CTL, 0, AR2315_CONFIG_PCIAHB | 344 AR2315_CONFIG_PCIAHB_BRIDGE); 345 346 /* Configure as PCI host with DMA */ 347 ar2315_rst_reg_write(AR2315_PCICLK, AR2315_PCICLK_PLLC_CLKM | 348 (AR2315_PCICLK_IN_FREQ_DIV_6 << 349 AR2315_PCICLK_DIV_S)); 350 ar2315_rst_reg_mask(AR2315_AHB_ARB_CTL, 0, AR2315_ARB_PCI); 351 ar2315_rst_reg_mask(AR2315_IF_CTL, AR2315_IF_PCI_CLK_MASK | 352 AR2315_IF_MASK, AR2315_IF_PCI | 353 AR2315_IF_PCI_HOST | AR2315_IF_PCI_INTR | 354 (AR2315_IF_PCI_CLK_OUTPUT_CLK << 355 AR2315_IF_PCI_CLK_SHIFT)); 356 357 platform_device_register_simple("ar2315-pci", -1, 358 ar2315_pci_res, 359 ARRAY_SIZE(ar2315_pci_res)); 360 } 361 #endif 362 } 363