xref: /linux/arch/arm/mach-imx/src.c (revision c75c5ab575af7db707689cdbb5a5c458e9a034bb)
1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  * Copyright 2011 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/init.h>
14 #include <linux/io.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/smp.h>
18 #include <asm/smp_plat.h>
19 
20 #define SRC_SCR				0x000
21 #define SRC_GPR1			0x020
22 #define BP_SRC_SCR_WARM_RESET_ENABLE	0
23 #define BP_SRC_SCR_CORE1_RST		14
24 #define BP_SRC_SCR_CORE1_ENABLE		22
25 
26 static void __iomem *src_base;
27 
28 void imx_enable_cpu(int cpu, bool enable)
29 {
30 	u32 mask, val;
31 
32 	cpu = cpu_logical_map(cpu);
33 	mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1);
34 	val = readl_relaxed(src_base + SRC_SCR);
35 	val = enable ? val | mask : val & ~mask;
36 	writel_relaxed(val, src_base + SRC_SCR);
37 }
38 
39 void imx_set_cpu_jump(int cpu, void *jump_addr)
40 {
41 	cpu = cpu_logical_map(cpu);
42 	writel_relaxed(virt_to_phys(jump_addr),
43 		       src_base + SRC_GPR1 + cpu * 8);
44 }
45 
46 u32 imx_get_cpu_arg(int cpu)
47 {
48 	cpu = cpu_logical_map(cpu);
49 	return readl_relaxed(src_base + SRC_GPR1 + cpu * 8 + 4);
50 }
51 
52 void imx_set_cpu_arg(int cpu, u32 arg)
53 {
54 	cpu = cpu_logical_map(cpu);
55 	writel_relaxed(arg, src_base + SRC_GPR1 + cpu * 8 + 4);
56 }
57 
58 void imx_src_prepare_restart(void)
59 {
60 	u32 val;
61 
62 	/* clear enable bits of secondary cores */
63 	val = readl_relaxed(src_base + SRC_SCR);
64 	val &= ~(0x7 << BP_SRC_SCR_CORE1_ENABLE);
65 	writel_relaxed(val, src_base + SRC_SCR);
66 
67 	/* clear persistent entry register of primary core */
68 	writel_relaxed(0, src_base + SRC_GPR1);
69 }
70 
71 void __init imx_src_init(void)
72 {
73 	struct device_node *np;
74 	u32 val;
75 
76 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-src");
77 	src_base = of_iomap(np, 0);
78 	WARN_ON(!src_base);
79 
80 	/*
81 	 * force warm reset sources to generate cold reset
82 	 * for a more reliable restart
83 	 */
84 	val = readl_relaxed(src_base + SRC_SCR);
85 	val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE);
86 	writel_relaxed(val, src_base + SRC_SCR);
87 }
88