1 /*
2  * Lowlevel setup for EXYNOS5 based board
3  *
4  * Copyright (C) 2013 Samsung Electronics
5  * Rajeshwari Shinde <rajeshwari.s@samsung.com>
6  *
7  * See file CREDITS for list of people who contributed to this
8  * project.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  */
25 
26 #include <config.h>
27 #include <debug_uart.h>
28 #include <asm/system.h>
29 #include <init.h>
30 #include <asm/arch/cpu.h>
31 #include <asm/arch/dmc.h>
32 #include <asm/arch/power.h>
33 #include <asm/arch/tzpc.h>
34 #include <asm/arch/periph.h>
35 #include <asm/arch/pinmux.h>
36 #include <asm/arch/system.h>
37 #include <asm/armv7.h>
38 #include "common_setup.h"
39 #include "exynos5_setup.h"
40 
41 /* These are the things we can do during low-level init */
42 enum {
43 	DO_WAKEUP	= 1 << 0,
44 	DO_CLOCKS	= 1 << 1,
45 	DO_MEM_RESET	= 1 << 2,
46 	DO_UART		= 1 << 3,
47 	DO_POWER	= 1 << 4,
48 };
49 
50 #ifdef CONFIG_EXYNOS5420
51 
52 /* Address for relocating helper code (Last 4 KB of IRAM) */
53 #define EXYNOS_RELOCATE_CODE_BASE	(CFG_IRAM_TOP - 0x1000)
54 
55 /*
56  * Power up secondary CPUs.
57  */
secondary_cpu_start(void)58 static void secondary_cpu_start(void)
59 {
60 	v7_enable_smp(EXYNOS5420_INFORM_BASE);
61 	svc32_mode_en();
62 	branch_bx(EXYNOS_RELOCATE_CODE_BASE);
63 }
64 
65 /*
66  * This is the entry point of hotplug-in and
67  * cluster switching.
68  */
low_power_start(void)69 static void low_power_start(void)
70 {
71 	uint32_t val, reg_val;
72 
73 	reg_val = readl(EXYNOS5420_SPARE_BASE);
74 	if (reg_val != CPU_RST_FLAG_VAL) {
75 		writel(0x0, CFG_LOWPOWER_FLAG);
76 		branch_bx(0x0);
77 	}
78 
79 	reg_val = readl(CFG_PHY_IRAM_BASE + 0x4);
80 	if (reg_val != (uint32_t)&low_power_start) {
81 		/* Store jump address as low_power_start if not present */
82 		writel((uint32_t)&low_power_start, CFG_PHY_IRAM_BASE + 0x4);
83 		dsb();
84 		sev();
85 	}
86 
87 	/* Set the CPU to SVC32 mode */
88 	svc32_mode_en();
89 
90 #ifndef CONFIG_SYS_L2CACHE_OFF
91 	/* Read MIDR for Primary Part Number */
92 	mrc_midr(val);
93 	val = (val >> 4);
94 	val &= 0xf;
95 
96 	if (val == 0xf) {
97 		configure_l2_ctlr();
98 		configure_l2_actlr();
99 		v7_enable_l2_hazard_detect();
100 	}
101 #endif
102 
103 	/* Invalidate L1 & TLB */
104 	val = 0x0;
105 	mcr_tlb(val);
106 	mcr_icache(val);
107 
108 	/* Disable MMU stuff and caches */
109 	mrc_sctlr(val);
110 
111 	val &= ~((0x2 << 12) | 0x7);
112 	val |= ((0x1 << 12) | (0x8 << 8) | 0x2);
113 	mcr_sctlr(val);
114 
115 	/* CPU state is hotplug or reset */
116 	secondary_cpu_start();
117 
118 	/* Core should not enter into WFI here */
119 	wfi();
120 }
121 
122 /*
123  * Pointer to this function is stored in iRam which is used
124  * for jump and power down of a specific core.
125  */
power_down_core(void)126 static void power_down_core(void)
127 {
128 	uint32_t tmp, core_id, core_config;
129 
130 	/* Get the unique core id */
131 	/*
132 	 * Multiprocessor Affinity Register
133 	 * [11:8]	Cluster ID
134 	 * [1:0]	CPU ID
135 	 */
136 	mrc_mpafr(core_id);
137 	tmp = core_id & 0x3;
138 	core_id = (core_id >> 6) & ~3;
139 	core_id |= tmp;
140 	core_id &= 0x3f;
141 
142 	/* Set the status of the core to low */
143 	core_config = (core_id * CPU_CONFIG_STATUS_OFFSET);
144 	core_config += EXYNOS5420_CPU_CONFIG_BASE;
145 	writel(0x0, core_config);
146 
147 	/* Core enter WFI */
148 	wfi();
149 }
150 
151 /*
152  * Configurations for secondary cores are inapt at this stage.
153  * Reconfigure secondary cores. Shutdown and change the status
154  * of all cores except the primary core.
155  */
secondary_cores_configure(void)156 static void secondary_cores_configure(void)
157 {
158 	/* Clear secondary boot iRAM base */
159 	writel(0x0, (EXYNOS_RELOCATE_CODE_BASE + 0x1C));
160 
161 	/* set lowpower flag and address */
162 	writel(CPU_RST_FLAG_VAL, CFG_LOWPOWER_FLAG);
163 	writel((uint32_t)&low_power_start, CFG_LOWPOWER_ADDR);
164 	writel(CPU_RST_FLAG_VAL, EXYNOS5420_SPARE_BASE);
165 	/* Store jump address for power down */
166 	writel((uint32_t)&power_down_core, CFG_PHY_IRAM_BASE + 0x4);
167 
168 	/* Need all core power down check */
169 	dsb();
170 	sev();
171 }
172 
173 extern void relocate_wait_code(void);
174 #endif
175 
do_lowlevel_init(void)176 int do_lowlevel_init(void)
177 {
178 	uint32_t reset_status;
179 	int actions = 0;
180 
181 	arch_cpu_init();
182 
183 #if !defined(CONFIG_SYS_L2CACHE_OFF) && defined(CONFIG_EXYNOS5420)
184 	/*
185 	 * Init L2 cache parameters here for use by boot and resume
186 	 *
187 	 * These are here instead of in v7_outer_cache_enable() so that the
188 	 * L2 cache settings get properly set even at resume time or if we're
189 	 * running U-Boot with the cache off.  The kernel still needs us to
190 	 * set these for it.
191 	 */
192 	configure_l2_ctlr();
193 	configure_l2_actlr();
194 	dsb();
195 	isb();
196 
197 	relocate_wait_code();
198 
199 	/* Reconfigure secondary cores */
200 	secondary_cores_configure();
201 #endif
202 
203 	reset_status = get_reset_status();
204 
205 	switch (reset_status) {
206 	case S5P_CHECK_SLEEP:
207 		actions = DO_CLOCKS | DO_WAKEUP;
208 		break;
209 	case S5P_CHECK_DIDLE:
210 	case S5P_CHECK_LPA:
211 		actions = DO_WAKEUP;
212 		break;
213 	default:
214 		/* This is a normal boot (not a wake from sleep) */
215 		actions = DO_CLOCKS | DO_MEM_RESET | DO_POWER;
216 	}
217 
218 	if (actions & DO_POWER)
219 		set_ps_hold_ctrl();
220 
221 	if (actions & DO_CLOCKS) {
222 		system_clock_init();
223 #ifdef CONFIG_DEBUG_UART
224 #if (defined(CONFIG_XPL_BUILD) && defined(CONFIG_SPL_SERIAL)) || \
225     !defined(CONFIG_XPL_BUILD)
226 		exynos_pinmux_config(PERIPH_ID_UART3, PINMUX_FLAG_NONE);
227 		debug_uart_init();
228 #endif
229 #endif
230 		mem_ctrl_init(actions & DO_MEM_RESET);
231 		tzpc_init();
232 	}
233 
234 	return actions & DO_WAKEUP;
235 }
236