xref: /openbmc/linux/arch/mips/bcm63xx/prom.c (revision 2cf1c348)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
7  */
8 
9 #include <linux/init.h>
10 #include <linux/memblock.h>
11 #include <linux/smp.h>
12 #include <asm/bootinfo.h>
13 #include <asm/bmips.h>
14 #include <asm/smp-ops.h>
15 #include <asm/mipsregs.h>
16 #include <bcm63xx_board.h>
17 #include <bcm63xx_cpu.h>
18 #include <bcm63xx_io.h>
19 #include <bcm63xx_regs.h>
20 
21 void __init prom_init(void)
22 {
23 	u32 reg, mask;
24 
25 	bcm63xx_cpu_init();
26 
27 	/* stop any running watchdog */
28 	bcm_wdt_writel(WDT_STOP_1, WDT_CTL_REG);
29 	bcm_wdt_writel(WDT_STOP_2, WDT_CTL_REG);
30 
31 	/* disable all hardware blocks clock for now */
32 	if (BCMCPU_IS_3368())
33 		mask = CKCTL_3368_ALL_SAFE_EN;
34 	else if (BCMCPU_IS_6328())
35 		mask = CKCTL_6328_ALL_SAFE_EN;
36 	else if (BCMCPU_IS_6338())
37 		mask = CKCTL_6338_ALL_SAFE_EN;
38 	else if (BCMCPU_IS_6345())
39 		mask = CKCTL_6345_ALL_SAFE_EN;
40 	else if (BCMCPU_IS_6348())
41 		mask = CKCTL_6348_ALL_SAFE_EN;
42 	else if (BCMCPU_IS_6358())
43 		mask = CKCTL_6358_ALL_SAFE_EN;
44 	else if (BCMCPU_IS_6362())
45 		mask = CKCTL_6362_ALL_SAFE_EN;
46 	else if (BCMCPU_IS_6368())
47 		mask = CKCTL_6368_ALL_SAFE_EN;
48 	else
49 		mask = 0;
50 
51 	reg = bcm_perf_readl(PERF_CKCTL_REG);
52 	reg &= ~mask;
53 	bcm_perf_writel(reg, PERF_CKCTL_REG);
54 
55 	/* do low level board init */
56 	board_prom_init();
57 
58 	/* set up SMP */
59 	if (!register_bmips_smp_ops()) {
60 		/*
61 		 * BCM6328 might not have its second CPU enabled, while BCM3368
62 		 * and BCM6358 need special handling for their shared TLB, so
63 		 * disable SMP for now.
64 		 */
65 		if (BCMCPU_IS_6328()) {
66 			reg = bcm_readl(BCM_6328_OTP_BASE +
67 					OTP_USER_BITS_6328_REG(3));
68 
69 			if (reg & OTP_6328_REG3_TP1_DISABLED)
70 				bmips_smp_enabled = 0;
71 		} else if (BCMCPU_IS_3368() || BCMCPU_IS_6358()) {
72 			bmips_smp_enabled = 0;
73 		}
74 
75 		if (!bmips_smp_enabled)
76 			return;
77 
78 		/*
79 		 * The bootloader has set up the CPU1 reset vector at
80 		 * 0xa000_0200.
81 		 * This conflicts with the special interrupt vector (IV).
82 		 * The bootloader has also set up CPU1 to respond to the wrong
83 		 * IPI interrupt.
84 		 * Here we will start up CPU1 in the background and ask it to
85 		 * reconfigure itself then go back to sleep.
86 		 */
87 		memcpy((void *)0xa0000200, bmips_smp_movevec, 0x20);
88 		__sync();
89 		set_c0_cause(C_SW0);
90 		cpumask_set_cpu(1, &bmips_booted_mask);
91 
92 		/*
93 		 * FIXME: we really should have some sort of hazard barrier here
94 		 */
95 	}
96 }
97