xref: /linux/arch/arm/mach-omap2/omap4-common.c (revision 3c53c6255d598db7084c5c3d7553d7200e857818)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP4 specific common source file.
4  *
5  * Copyright (C) 2010 Texas Instruments, Inc.
6  * Author:
7  *	Santosh Shilimkar <santosh.shilimkar@ti.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/irqchip.h>
15 #include <linux/platform_device.h>
16 #include <linux/memblock.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_platform.h>
19 #include <linux/export.h>
20 #include <linux/irqchip/arm-gic.h>
21 #include <linux/of_address.h>
22 #include <linux/reboot.h>
23 #include <linux/genalloc.h>
24 
25 #include <asm/hardware/cache-l2x0.h>
26 #include <asm/mach/map.h>
27 #include <asm/memblock.h>
28 #include <asm/smp_twd.h>
29 
30 #include "omap-wakeupgen.h"
31 #include "soc.h"
32 #include "iomap.h"
33 #include "common.h"
34 #include "prminst44xx.h"
35 #include "prcm_mpu44xx.h"
36 #include "omap4-sar-layout.h"
37 #include "omap-secure.h"
38 #include "sram.h"
39 
40 #ifdef CONFIG_CACHE_L2X0
41 static void __iomem *l2cache_base;
42 #endif
43 
44 static void __iomem *sar_ram_base;
45 static void __iomem *gic_dist_base_addr;
46 static void __iomem *twd_base;
47 
48 #define IRQ_LOCALTIMER		29
49 
50 #ifdef CONFIG_OMAP_INTERCONNECT_BARRIER
51 
52 /* Used to implement memory barrier on DRAM path */
53 #define OMAP4_DRAM_BARRIER_VA			0xfe600000
54 
55 static void __iomem *dram_sync, *sram_sync;
56 static phys_addr_t dram_sync_paddr;
57 static u32 dram_sync_size;
58 
59 /*
60  * The OMAP4 bus structure contains asynchronous bridges which can buffer
61  * data writes from the MPU. These asynchronous bridges can be found on
62  * paths between the MPU to EMIF, and the MPU to L3 interconnects.
63  *
64  * We need to be careful about re-ordering which can happen as a result
65  * of different accesses being performed via different paths, and
66  * therefore different asynchronous bridges.
67  */
68 
69 /*
70  * OMAP4 interconnect barrier which is called for each mb() and wmb().
71  * This is to ensure that normal paths to DRAM (normal memory, cacheable
72  * accesses) are properly synchronised with writes to DMA coherent memory
73  * (normal memory, uncacheable) and device writes.
74  *
75  * The mb() and wmb() barriers only operate only on the MPU->MA->EMIF
76  * path, as we need to ensure that data is visible to other system
77  * masters prior to writes to those system masters being seen.
78  *
79  * Note: the SRAM path is not synchronised via mb() and wmb().
80  */
81 static void omap4_mb(void)
82 {
83 	if (dram_sync)
84 		writel_relaxed(0, dram_sync);
85 }
86 
87 /*
88  * OMAP4 Errata i688 - asynchronous bridge corruption when entering WFI.
89  *
90  * If a data is stalled inside asynchronous bridge because of back
91  * pressure, it may be accepted multiple times, creating pointer
92  * misalignment that will corrupt next transfers on that data path until
93  * next reset of the system. No recovery procedure once the issue is hit,
94  * the path remains consistently broken.
95  *
96  * Async bridges can be found on paths between MPU to EMIF and MPU to L3
97  * interconnects.
98  *
99  * This situation can happen only when the idle is initiated by a Master
100  * Request Disconnection (which is trigged by software when executing WFI
101  * on the CPU).
102  *
103  * The work-around for this errata needs all the initiators connected
104  * through an async bridge to ensure that data path is properly drained
105  * before issuing WFI. This condition will be met if one Strongly ordered
106  * access is performed to the target right before executing the WFI.
107  *
108  * In MPU case, L3 T2ASYNC FIFO and DDR T2ASYNC FIFO needs to be drained.
109  * IO barrier ensure that there is no synchronisation loss on initiators
110  * operating on both interconnect port simultaneously.
111  *
112  * This is a stronger version of the OMAP4 memory barrier below, and
113  * operates on both the MPU->MA->EMIF path but also the MPU->OCP path
114  * as well, and is necessary prior to executing a WFI.
115  */
116 void omap_interconnect_sync(void)
117 {
118 	if (dram_sync && sram_sync) {
119 		writel_relaxed(readl_relaxed(dram_sync), dram_sync);
120 		writel_relaxed(readl_relaxed(sram_sync), sram_sync);
121 		isb();
122 	}
123 }
124 
125 static int __init omap4_sram_init(void)
126 {
127 	struct device_node *np;
128 	struct gen_pool *sram_pool;
129 
130 	np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
131 	if (!np)
132 		pr_warn("%s:Unable to allocate sram needed to handle errata I688\n",
133 			__func__);
134 	sram_pool = of_gen_pool_get(np, "sram", 0);
135 	if (!sram_pool)
136 		pr_warn("%s:Unable to get sram pool needed to handle errata I688\n",
137 			__func__);
138 	else
139 		sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE);
140 
141 	return 0;
142 }
143 omap_arch_initcall(omap4_sram_init);
144 
145 /* Steal one page physical memory for barrier implementation */
146 void __init omap_barrier_reserve_memblock(void)
147 {
148 	dram_sync_size = ALIGN(PAGE_SIZE, SZ_1M);
149 	dram_sync_paddr = arm_memblock_steal(dram_sync_size, SZ_1M);
150 }
151 
152 void __init omap_barriers_init(void)
153 {
154 	struct map_desc dram_io_desc[1];
155 
156 	dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA;
157 	dram_io_desc[0].pfn = __phys_to_pfn(dram_sync_paddr);
158 	dram_io_desc[0].length = dram_sync_size;
159 	dram_io_desc[0].type = MT_MEMORY_RW_SO;
160 	iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc));
161 	dram_sync = (void __iomem *) dram_io_desc[0].virtual;
162 
163 	pr_info("OMAP4: Map %pa to %p for dram barrier\n",
164 		&dram_sync_paddr, dram_sync);
165 
166 	soc_mb = omap4_mb;
167 }
168 
169 #endif
170 
171 void gic_dist_disable(void)
172 {
173 	if (gic_dist_base_addr)
174 		writel_relaxed(0x0, gic_dist_base_addr + GIC_DIST_CTRL);
175 }
176 
177 void gic_dist_enable(void)
178 {
179 	if (gic_dist_base_addr)
180 		writel_relaxed(0x1, gic_dist_base_addr + GIC_DIST_CTRL);
181 }
182 
183 bool gic_dist_disabled(void)
184 {
185 	return !(readl_relaxed(gic_dist_base_addr + GIC_DIST_CTRL) & 0x1);
186 }
187 
188 void gic_timer_retrigger(void)
189 {
190 	u32 twd_int = readl_relaxed(twd_base + TWD_TIMER_INTSTAT);
191 	u32 gic_int = readl_relaxed(gic_dist_base_addr + GIC_DIST_PENDING_SET);
192 	u32 twd_ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL);
193 
194 	if (twd_int && !(gic_int & BIT(IRQ_LOCALTIMER))) {
195 		/*
196 		 * The local timer interrupt got lost while the distributor was
197 		 * disabled.  Ack the pending interrupt, and retrigger it.
198 		 */
199 		pr_warn("%s: lost localtimer interrupt\n", __func__);
200 		writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT);
201 		if (!(twd_ctrl & TWD_TIMER_CONTROL_PERIODIC)) {
202 			writel_relaxed(1, twd_base + TWD_TIMER_COUNTER);
203 			twd_ctrl |= TWD_TIMER_CONTROL_ENABLE;
204 			writel_relaxed(twd_ctrl, twd_base + TWD_TIMER_CONTROL);
205 		}
206 	}
207 }
208 
209 #ifdef CONFIG_CACHE_L2X0
210 
211 void __iomem *omap4_get_l2cache_base(void)
212 {
213 	return l2cache_base;
214 }
215 
216 void omap4_l2c310_write_sec(unsigned long val, unsigned reg)
217 {
218 	unsigned smc_op;
219 
220 	switch (reg) {
221 	case L2X0_CTRL:
222 		smc_op = OMAP4_MON_L2X0_CTRL_INDEX;
223 		break;
224 
225 	case L2X0_AUX_CTRL:
226 		smc_op = OMAP4_MON_L2X0_AUXCTRL_INDEX;
227 		break;
228 
229 	case L2X0_DEBUG_CTRL:
230 		smc_op = OMAP4_MON_L2X0_DBG_CTRL_INDEX;
231 		break;
232 
233 	case L310_PREFETCH_CTRL:
234 		smc_op = OMAP4_MON_L2X0_PREFETCH_INDEX;
235 		break;
236 
237 	case L310_POWER_CTRL:
238 		pr_info_once("OMAP L2C310: ROM does not support power control setting\n");
239 		return;
240 
241 	default:
242 		WARN_ONCE(1, "OMAP L2C310: ignoring write to reg 0x%x\n", reg);
243 		return;
244 	}
245 
246 	omap_smc1(smc_op, val);
247 }
248 
249 int __init omap_l2_cache_init(void)
250 {
251 	/* Static mapping, never released */
252 	l2cache_base = ioremap(OMAP44XX_L2CACHE_BASE, SZ_4K);
253 	if (WARN_ON(!l2cache_base))
254 		return -ENOMEM;
255 	return 0;
256 }
257 #endif
258 
259 void __iomem *omap4_get_sar_ram_base(void)
260 {
261 	return sar_ram_base;
262 }
263 
264 /*
265  * SAR RAM used to save and restore the HW context in low power modes.
266  * Note that we need to initialize this very early for kexec. See
267  * omap4_mpuss_early_init().
268  */
269 void __init omap4_sar_ram_init(void)
270 {
271 	unsigned long sar_base;
272 
273 	/*
274 	 * To avoid code running on other OMAPs in
275 	 * multi-omap builds
276 	 */
277 	if (cpu_is_omap44xx())
278 		sar_base = OMAP44XX_SAR_RAM_BASE;
279 	else if (soc_is_omap54xx())
280 		sar_base = OMAP54XX_SAR_RAM_BASE;
281 	else
282 		return;
283 
284 	/* Static mapping, never released */
285 	sar_ram_base = ioremap(sar_base, SZ_16K);
286 	if (WARN_ON(!sar_ram_base))
287 		return;
288 }
289 
290 static const struct of_device_id intc_match[] = {
291 	{ .compatible = "ti,omap4-wugen-mpu", },
292 	{ .compatible = "ti,omap5-wugen-mpu", },
293 	{ },
294 };
295 
296 static struct device_node *intc_node;
297 
298 void __init omap_gic_of_init(void)
299 {
300 	struct device_node *np;
301 
302 	intc_node = of_find_matching_node(NULL, intc_match);
303 	if (WARN_ON(!intc_node)) {
304 		pr_err("No WUGEN found in DT, system will misbehave.\n");
305 		pr_err("UPDATE YOUR DEVICE TREE!\n");
306 	}
307 
308 	/* Extract GIC distributor and TWD bases for OMAP4460 ROM Errata WA */
309 	if (!cpu_is_omap446x())
310 		goto skip_errata_init;
311 
312 	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-gic");
313 	gic_dist_base_addr = of_iomap(np, 0);
314 	WARN_ON(!gic_dist_base_addr);
315 
316 	np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-twd-timer");
317 	twd_base = of_iomap(np, 0);
318 	WARN_ON(!twd_base);
319 
320 skip_errata_init:
321 	irqchip_init();
322 }
323