1 /* 2 * OMAP4 specific common source file. 3 * 4 * Copyright (C) 2010 Texas Instruments, Inc. 5 * Author: 6 * Santosh Shilimkar <santosh.shilimkar@ti.com> 7 * 8 * 9 * This program is free software,you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include <linux/kernel.h> 15 #include <linux/init.h> 16 #include <linux/io.h> 17 #include <linux/irq.h> 18 #include <linux/irqchip.h> 19 #include <linux/platform_device.h> 20 #include <linux/memblock.h> 21 #include <linux/of_irq.h> 22 #include <linux/of_platform.h> 23 #include <linux/export.h> 24 #include <linux/irqchip/arm-gic.h> 25 #include <linux/of_address.h> 26 #include <linux/reboot.h> 27 #include <linux/genalloc.h> 28 29 #include <asm/hardware/cache-l2x0.h> 30 #include <asm/mach/map.h> 31 #include <asm/memblock.h> 32 #include <asm/smp_twd.h> 33 34 #include "omap-wakeupgen.h" 35 #include "soc.h" 36 #include "iomap.h" 37 #include "common.h" 38 #include "prminst44xx.h" 39 #include "prcm_mpu44xx.h" 40 #include "omap4-sar-layout.h" 41 #include "omap-secure.h" 42 #include "sram.h" 43 44 #ifdef CONFIG_CACHE_L2X0 45 static void __iomem *l2cache_base; 46 #endif 47 48 static void __iomem *sar_ram_base; 49 static void __iomem *gic_dist_base_addr; 50 static void __iomem *twd_base; 51 52 #define IRQ_LOCALTIMER 29 53 54 #ifdef CONFIG_OMAP_INTERCONNECT_BARRIER 55 56 /* Used to implement memory barrier on DRAM path */ 57 #define OMAP4_DRAM_BARRIER_VA 0xfe600000 58 59 static void __iomem *dram_sync, *sram_sync; 60 static phys_addr_t dram_sync_paddr; 61 static u32 dram_sync_size; 62 63 /* 64 * The OMAP4 bus structure contains asynchronous bridges which can buffer 65 * data writes from the MPU. These asynchronous bridges can be found on 66 * paths between the MPU to EMIF, and the MPU to L3 interconnects. 67 * 68 * We need to be careful about re-ordering which can happen as a result 69 * of different accesses being performed via different paths, and 70 * therefore different asynchronous bridges. 71 */ 72 73 /* 74 * OMAP4 interconnect barrier which is called for each mb() and wmb(). 75 * This is to ensure that normal paths to DRAM (normal memory, cacheable 76 * accesses) are properly synchronised with writes to DMA coherent memory 77 * (normal memory, uncacheable) and device writes. 78 * 79 * The mb() and wmb() barriers only operate only on the MPU->MA->EMIF 80 * path, as we need to ensure that data is visible to other system 81 * masters prior to writes to those system masters being seen. 82 * 83 * Note: the SRAM path is not synchronised via mb() and wmb(). 84 */ 85 static void omap4_mb(void) 86 { 87 if (dram_sync) 88 writel_relaxed(0, dram_sync); 89 } 90 91 /* 92 * OMAP4 Errata i688 - asynchronous bridge corruption when entering WFI. 93 * 94 * If a data is stalled inside asynchronous bridge because of back 95 * pressure, it may be accepted multiple times, creating pointer 96 * misalignment that will corrupt next transfers on that data path until 97 * next reset of the system. No recovery procedure once the issue is hit, 98 * the path remains consistently broken. 99 * 100 * Async bridges can be found on paths between MPU to EMIF and MPU to L3 101 * interconnects. 102 * 103 * This situation can happen only when the idle is initiated by a Master 104 * Request Disconnection (which is trigged by software when executing WFI 105 * on the CPU). 106 * 107 * The work-around for this errata needs all the initiators connected 108 * through an async bridge to ensure that data path is properly drained 109 * before issuing WFI. This condition will be met if one Strongly ordered 110 * access is performed to the target right before executing the WFI. 111 * 112 * In MPU case, L3 T2ASYNC FIFO and DDR T2ASYNC FIFO needs to be drained. 113 * IO barrier ensure that there is no synchronisation loss on initiators 114 * operating on both interconnect port simultaneously. 115 * 116 * This is a stronger version of the OMAP4 memory barrier below, and 117 * operates on both the MPU->MA->EMIF path but also the MPU->OCP path 118 * as well, and is necessary prior to executing a WFI. 119 */ 120 void omap_interconnect_sync(void) 121 { 122 if (dram_sync && sram_sync) { 123 writel_relaxed(readl_relaxed(dram_sync), dram_sync); 124 writel_relaxed(readl_relaxed(sram_sync), sram_sync); 125 isb(); 126 } 127 } 128 129 static int __init omap4_sram_init(void) 130 { 131 struct device_node *np; 132 struct gen_pool *sram_pool; 133 134 np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu"); 135 if (!np) 136 pr_warn("%s:Unable to allocate sram needed to handle errata I688\n", 137 __func__); 138 sram_pool = of_gen_pool_get(np, "sram", 0); 139 if (!sram_pool) 140 pr_warn("%s:Unable to get sram pool needed to handle errata I688\n", 141 __func__); 142 else 143 sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE); 144 145 return 0; 146 } 147 omap_arch_initcall(omap4_sram_init); 148 149 /* Steal one page physical memory for barrier implementation */ 150 void __init omap_barrier_reserve_memblock(void) 151 { 152 dram_sync_size = ALIGN(PAGE_SIZE, SZ_1M); 153 dram_sync_paddr = arm_memblock_steal(dram_sync_size, SZ_1M); 154 } 155 156 void __init omap_barriers_init(void) 157 { 158 struct map_desc dram_io_desc[1]; 159 160 dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA; 161 dram_io_desc[0].pfn = __phys_to_pfn(dram_sync_paddr); 162 dram_io_desc[0].length = dram_sync_size; 163 dram_io_desc[0].type = MT_MEMORY_RW_SO; 164 iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc)); 165 dram_sync = (void __iomem *) dram_io_desc[0].virtual; 166 167 pr_info("OMAP4: Map %pa to %p for dram barrier\n", 168 &dram_sync_paddr, dram_sync); 169 170 soc_mb = omap4_mb; 171 } 172 173 #endif 174 175 void gic_dist_disable(void) 176 { 177 if (gic_dist_base_addr) 178 writel_relaxed(0x0, gic_dist_base_addr + GIC_DIST_CTRL); 179 } 180 181 void gic_dist_enable(void) 182 { 183 if (gic_dist_base_addr) 184 writel_relaxed(0x1, gic_dist_base_addr + GIC_DIST_CTRL); 185 } 186 187 bool gic_dist_disabled(void) 188 { 189 return !(readl_relaxed(gic_dist_base_addr + GIC_DIST_CTRL) & 0x1); 190 } 191 192 void gic_timer_retrigger(void) 193 { 194 u32 twd_int = readl_relaxed(twd_base + TWD_TIMER_INTSTAT); 195 u32 gic_int = readl_relaxed(gic_dist_base_addr + GIC_DIST_PENDING_SET); 196 u32 twd_ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL); 197 198 if (twd_int && !(gic_int & BIT(IRQ_LOCALTIMER))) { 199 /* 200 * The local timer interrupt got lost while the distributor was 201 * disabled. Ack the pending interrupt, and retrigger it. 202 */ 203 pr_warn("%s: lost localtimer interrupt\n", __func__); 204 writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT); 205 if (!(twd_ctrl & TWD_TIMER_CONTROL_PERIODIC)) { 206 writel_relaxed(1, twd_base + TWD_TIMER_COUNTER); 207 twd_ctrl |= TWD_TIMER_CONTROL_ENABLE; 208 writel_relaxed(twd_ctrl, twd_base + TWD_TIMER_CONTROL); 209 } 210 } 211 } 212 213 #ifdef CONFIG_CACHE_L2X0 214 215 void __iomem *omap4_get_l2cache_base(void) 216 { 217 return l2cache_base; 218 } 219 220 void omap4_l2c310_write_sec(unsigned long val, unsigned reg) 221 { 222 unsigned smc_op; 223 224 switch (reg) { 225 case L2X0_CTRL: 226 smc_op = OMAP4_MON_L2X0_CTRL_INDEX; 227 break; 228 229 case L2X0_AUX_CTRL: 230 smc_op = OMAP4_MON_L2X0_AUXCTRL_INDEX; 231 break; 232 233 case L2X0_DEBUG_CTRL: 234 smc_op = OMAP4_MON_L2X0_DBG_CTRL_INDEX; 235 break; 236 237 case L310_PREFETCH_CTRL: 238 smc_op = OMAP4_MON_L2X0_PREFETCH_INDEX; 239 break; 240 241 case L310_POWER_CTRL: 242 pr_info_once("OMAP L2C310: ROM does not support power control setting\n"); 243 return; 244 245 default: 246 WARN_ONCE(1, "OMAP L2C310: ignoring write to reg 0x%x\n", reg); 247 return; 248 } 249 250 omap_smc1(smc_op, val); 251 } 252 253 int __init omap_l2_cache_init(void) 254 { 255 /* Static mapping, never released */ 256 l2cache_base = ioremap(OMAP44XX_L2CACHE_BASE, SZ_4K); 257 if (WARN_ON(!l2cache_base)) 258 return -ENOMEM; 259 return 0; 260 } 261 #endif 262 263 void __iomem *omap4_get_sar_ram_base(void) 264 { 265 return sar_ram_base; 266 } 267 268 /* 269 * SAR RAM used to save and restore the HW context in low power modes. 270 * Note that we need to initialize this very early for kexec. See 271 * omap4_mpuss_early_init(). 272 */ 273 void __init omap4_sar_ram_init(void) 274 { 275 unsigned long sar_base; 276 277 /* 278 * To avoid code running on other OMAPs in 279 * multi-omap builds 280 */ 281 if (cpu_is_omap44xx()) 282 sar_base = OMAP44XX_SAR_RAM_BASE; 283 else if (soc_is_omap54xx()) 284 sar_base = OMAP54XX_SAR_RAM_BASE; 285 else 286 return; 287 288 /* Static mapping, never released */ 289 sar_ram_base = ioremap(sar_base, SZ_16K); 290 if (WARN_ON(!sar_ram_base)) 291 return; 292 } 293 294 static const struct of_device_id intc_match[] = { 295 { .compatible = "ti,omap4-wugen-mpu", }, 296 { .compatible = "ti,omap5-wugen-mpu", }, 297 { }, 298 }; 299 300 static struct device_node *intc_node; 301 302 void __init omap_gic_of_init(void) 303 { 304 struct device_node *np; 305 306 intc_node = of_find_matching_node(NULL, intc_match); 307 if (WARN_ON(!intc_node)) { 308 pr_err("No WUGEN found in DT, system will misbehave.\n"); 309 pr_err("UPDATE YOUR DEVICE TREE!\n"); 310 } 311 312 /* Extract GIC distributor and TWD bases for OMAP4460 ROM Errata WA */ 313 if (!cpu_is_omap446x()) 314 goto skip_errata_init; 315 316 np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-gic"); 317 gic_dist_base_addr = of_iomap(np, 0); 318 WARN_ON(!gic_dist_base_addr); 319 320 np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-twd-timer"); 321 twd_base = of_iomap(np, 0); 322 WARN_ON(!twd_base); 323 324 skip_errata_init: 325 irqchip_init(); 326 } 327