xref: /openbmc/linux/arch/mips/alchemy/common/power.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * BRIEF MODULE DESCRIPTION
3  *	Au1xx0 Power Management routines.
4  *
5  * Copyright 2001, 2008 MontaVista Software Inc.
6  * Author: MontaVista Software, Inc. <source@mvista.com>
7  *
8  *  Some of the routines are right out of init/main.c, whose
9  *  copyrights apply here.
10  *
11  *  This program is free software; you can redistribute	 it and/or modify it
12  *  under  the terms of	 the GNU General  Public License as published by the
13  *  Free Software Foundation;  either version 2 of the	License, or (at your
14  *  option) any later version.
15  *
16  *  THIS  SOFTWARE  IS PROVIDED	  ``AS	IS'' AND   ANY	EXPRESS OR IMPLIED
17  *  WARRANTIES,	  INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
18  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
19  *  NO	EVENT  SHALL   THE AUTHOR  BE	 LIABLE FOR ANY	  DIRECT, INDIRECT,
20  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  *  NOT LIMITED	  TO, PROCUREMENT OF  SUBSTITUTE GOODS	OR SERVICES; LOSS OF
22  *  USE, DATA,	OR PROFITS; OR	BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
23  *  ANY THEORY OF LIABILITY, WHETHER IN	 CONTRACT, STRICT LIABILITY, OR TORT
24  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  *  You should have received a copy of the  GNU General Public License along
28  *  with this program; if not, write  to the Free Software Foundation, Inc.,
29  *  675 Mass Ave, Cambridge, MA 02139, USA.
30  */
31 
32 #include <linux/init.h>
33 #include <linux/pm.h>
34 #include <linux/sysctl.h>
35 #include <linux/jiffies.h>
36 
37 #include <asm/uaccess.h>
38 #include <asm/mach-au1x00/au1000.h>
39 
40 #ifdef CONFIG_PM
41 
42 /*
43  * We need to save/restore a bunch of core registers that are
44  * either volatile or reset to some state across a processor sleep.
45  * If reading a register doesn't provide a proper result for a
46  * later restore, we have to provide a function for loading that
47  * register and save a copy.
48  *
49  * We only have to save/restore registers that aren't otherwise
50  * done as part of a driver pm_* function.
51  */
52 static unsigned int sleep_usb[2];
53 static unsigned int sleep_sys_clocks[5];
54 static unsigned int sleep_sys_pinfunc;
55 static unsigned int sleep_static_memctlr[4][3];
56 
57 
58 static void save_core_regs(void)
59 {
60 #ifndef CONFIG_SOC_AU1200
61 	/* Shutdown USB host/device. */
62 	sleep_usb[0] = au_readl(USB_HOST_CONFIG);
63 
64 	/* There appears to be some undocumented reset register.... */
65 	au_writel(0, 0xb0100004);
66 	au_sync();
67 	au_writel(0, USB_HOST_CONFIG);
68 	au_sync();
69 
70 	sleep_usb[1] = au_readl(USBD_ENABLE);
71 	au_writel(0, USBD_ENABLE);
72 	au_sync();
73 
74 #else	/* AU1200 */
75 
76 	/* enable access to OTG mmio so we can save OTG CAP/MUX.
77 	 * FIXME: write an OTG driver and move this stuff there!
78 	 */
79 	au_writel(au_readl(USB_MSR_BASE + 4) | (1 << 6), USB_MSR_BASE + 4);
80 	au_sync();
81 	sleep_usb[0] = au_readl(0xb4020020);	/* OTG_CAP */
82 	sleep_usb[1] = au_readl(0xb4020024);	/* OTG_MUX */
83 #endif
84 
85 	/* Clocks and PLLs. */
86 	sleep_sys_clocks[0] = au_readl(SYS_FREQCTRL0);
87 	sleep_sys_clocks[1] = au_readl(SYS_FREQCTRL1);
88 	sleep_sys_clocks[2] = au_readl(SYS_CLKSRC);
89 	sleep_sys_clocks[3] = au_readl(SYS_CPUPLL);
90 	sleep_sys_clocks[4] = au_readl(SYS_AUXPLL);
91 
92 	/* pin mux config */
93 	sleep_sys_pinfunc = au_readl(SYS_PINFUNC);
94 
95 	/* Save the static memory controller configuration. */
96 	sleep_static_memctlr[0][0] = au_readl(MEM_STCFG0);
97 	sleep_static_memctlr[0][1] = au_readl(MEM_STTIME0);
98 	sleep_static_memctlr[0][2] = au_readl(MEM_STADDR0);
99 	sleep_static_memctlr[1][0] = au_readl(MEM_STCFG1);
100 	sleep_static_memctlr[1][1] = au_readl(MEM_STTIME1);
101 	sleep_static_memctlr[1][2] = au_readl(MEM_STADDR1);
102 	sleep_static_memctlr[2][0] = au_readl(MEM_STCFG2);
103 	sleep_static_memctlr[2][1] = au_readl(MEM_STTIME2);
104 	sleep_static_memctlr[2][2] = au_readl(MEM_STADDR2);
105 	sleep_static_memctlr[3][0] = au_readl(MEM_STCFG3);
106 	sleep_static_memctlr[3][1] = au_readl(MEM_STTIME3);
107 	sleep_static_memctlr[3][2] = au_readl(MEM_STADDR3);
108 }
109 
110 static void restore_core_regs(void)
111 {
112 	/* restore clock configuration.  Writing CPUPLL last will
113 	 * stall a bit and stabilize other clocks (unless this is
114 	 * one of those Au1000 with a write-only PLL, where we dont
115 	 * have a valid value)
116 	 */
117 	au_writel(sleep_sys_clocks[0], SYS_FREQCTRL0);
118 	au_writel(sleep_sys_clocks[1], SYS_FREQCTRL1);
119 	au_writel(sleep_sys_clocks[2], SYS_CLKSRC);
120 	au_writel(sleep_sys_clocks[4], SYS_AUXPLL);
121 	if (!au1xxx_cpu_has_pll_wo())
122 		au_writel(sleep_sys_clocks[3], SYS_CPUPLL);
123 	au_sync();
124 
125 	au_writel(sleep_sys_pinfunc, SYS_PINFUNC);
126 	au_sync();
127 
128 #ifndef CONFIG_SOC_AU1200
129 	au_writel(sleep_usb[0], USB_HOST_CONFIG);
130 	au_writel(sleep_usb[1], USBD_ENABLE);
131 	au_sync();
132 #else
133 	/* enable access to OTG memory */
134 	au_writel(au_readl(USB_MSR_BASE + 4) | (1 << 6), USB_MSR_BASE + 4);
135 	au_sync();
136 
137 	/* restore OTG caps and port mux. */
138 	au_writel(sleep_usb[0], 0xb4020020 + 0);	/* OTG_CAP */
139 	au_sync();
140 	au_writel(sleep_usb[1], 0xb4020020 + 4);	/* OTG_MUX */
141 	au_sync();
142 #endif
143 
144 	/* Restore the static memory controller configuration. */
145 	au_writel(sleep_static_memctlr[0][0], MEM_STCFG0);
146 	au_writel(sleep_static_memctlr[0][1], MEM_STTIME0);
147 	au_writel(sleep_static_memctlr[0][2], MEM_STADDR0);
148 	au_writel(sleep_static_memctlr[1][0], MEM_STCFG1);
149 	au_writel(sleep_static_memctlr[1][1], MEM_STTIME1);
150 	au_writel(sleep_static_memctlr[1][2], MEM_STADDR1);
151 	au_writel(sleep_static_memctlr[2][0], MEM_STCFG2);
152 	au_writel(sleep_static_memctlr[2][1], MEM_STTIME2);
153 	au_writel(sleep_static_memctlr[2][2], MEM_STADDR2);
154 	au_writel(sleep_static_memctlr[3][0], MEM_STCFG3);
155 	au_writel(sleep_static_memctlr[3][1], MEM_STTIME3);
156 	au_writel(sleep_static_memctlr[3][2], MEM_STADDR3);
157 }
158 
159 void au_sleep(void)
160 {
161 	int cpuid = alchemy_get_cputype();
162 	if (cpuid != ALCHEMY_CPU_UNKNOWN) {
163 		save_core_regs();
164 		if (cpuid <= ALCHEMY_CPU_AU1500)
165 			alchemy_sleep_au1000();
166 		else if (cpuid <= ALCHEMY_CPU_AU1200)
167 			alchemy_sleep_au1550();
168 		restore_core_regs();
169 	}
170 }
171 
172 #endif	/* CONFIG_PM */
173