xref: /linux/arch/arm/mach-imx/src.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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 
19 #define SRC_SCR				0x000
20 #define SRC_GPR1			0x020
21 #define BP_SRC_SCR_WARM_RESET_ENABLE	0
22 #define BP_SRC_SCR_CORE1_RST		14
23 #define BP_SRC_SCR_CORE1_ENABLE		22
24 
25 static void __iomem *src_base;
26 
27 #ifndef CONFIG_SMP
28 #define cpu_logical_map(cpu)		0
29 #endif
30 
31 void imx_enable_cpu(int cpu, bool enable)
32 {
33 	u32 mask, val;
34 
35 	cpu = cpu_logical_map(cpu);
36 	mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1);
37 	val = readl_relaxed(src_base + SRC_SCR);
38 	val = enable ? val | mask : val & ~mask;
39 	writel_relaxed(val, src_base + SRC_SCR);
40 }
41 
42 void imx_set_cpu_jump(int cpu, void *jump_addr)
43 {
44 	cpu = cpu_logical_map(cpu);
45 	writel_relaxed(virt_to_phys(jump_addr),
46 		       src_base + SRC_GPR1 + cpu * 8);
47 }
48 
49 void imx_src_prepare_restart(void)
50 {
51 	u32 val;
52 
53 	/* clear enable bits of secondary cores */
54 	val = readl_relaxed(src_base + SRC_SCR);
55 	val &= ~(0x7 << BP_SRC_SCR_CORE1_ENABLE);
56 	writel_relaxed(val, src_base + SRC_SCR);
57 
58 	/* clear persistent entry register of primary core */
59 	writel_relaxed(0, src_base + SRC_GPR1);
60 }
61 
62 void __init imx_src_init(void)
63 {
64 	struct device_node *np;
65 	u32 val;
66 
67 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-src");
68 	src_base = of_iomap(np, 0);
69 	WARN_ON(!src_base);
70 
71 	/*
72 	 * force warm reset sources to generate cold reset
73 	 * for a more reliable restart
74 	 */
75 	val = readl_relaxed(src_base + SRC_SCR);
76 	val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE);
77 	writel_relaxed(val, src_base + SRC_SCR);
78 }
79