xref: /linux/arch/mips/sibyte/bcm1480/smp.c (revision d527eef5b7f151320921f0ff7a88297cefc5be72)
1 /*
2  * Copyright (C) 2001,2002,2004 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17  */
18 
19 #include <linux/init.h>
20 #include <linux/delay.h>
21 #include <linux/smp.h>
22 #include <linux/kernel_stat.h>
23 
24 #include <asm/mmu_context.h>
25 #include <asm/io.h>
26 #include <asm/sibyte/sb1250.h>
27 #include <asm/sibyte/bcm1480_regs.h>
28 #include <asm/sibyte/bcm1480_int.h>
29 
30 extern void smp_call_function_interrupt(void);
31 
32 /*
33  * These are routines for dealing with the bcm1480 smp capabilities
34  * independent of board/firmware
35  */
36 
37 static void *mailbox_0_set_regs[] = {
38 	IOADDR(A_BCM1480_IMR_CPU0_BASE + R_BCM1480_IMR_MAILBOX_0_SET_CPU),
39 	IOADDR(A_BCM1480_IMR_CPU1_BASE + R_BCM1480_IMR_MAILBOX_0_SET_CPU),
40 	IOADDR(A_BCM1480_IMR_CPU2_BASE + R_BCM1480_IMR_MAILBOX_0_SET_CPU),
41 	IOADDR(A_BCM1480_IMR_CPU3_BASE + R_BCM1480_IMR_MAILBOX_0_SET_CPU),
42 };
43 
44 static void *mailbox_0_clear_regs[] = {
45 	IOADDR(A_BCM1480_IMR_CPU0_BASE + R_BCM1480_IMR_MAILBOX_0_CLR_CPU),
46 	IOADDR(A_BCM1480_IMR_CPU1_BASE + R_BCM1480_IMR_MAILBOX_0_CLR_CPU),
47 	IOADDR(A_BCM1480_IMR_CPU2_BASE + R_BCM1480_IMR_MAILBOX_0_CLR_CPU),
48 	IOADDR(A_BCM1480_IMR_CPU3_BASE + R_BCM1480_IMR_MAILBOX_0_CLR_CPU),
49 };
50 
51 static void *mailbox_0_regs[] = {
52 	IOADDR(A_BCM1480_IMR_CPU0_BASE + R_BCM1480_IMR_MAILBOX_0_CPU),
53 	IOADDR(A_BCM1480_IMR_CPU1_BASE + R_BCM1480_IMR_MAILBOX_0_CPU),
54 	IOADDR(A_BCM1480_IMR_CPU2_BASE + R_BCM1480_IMR_MAILBOX_0_CPU),
55 	IOADDR(A_BCM1480_IMR_CPU3_BASE + R_BCM1480_IMR_MAILBOX_0_CPU),
56 };
57 
58 /*
59  * SMP init and finish on secondary CPUs
60  */
61 void bcm1480_smp_init(void)
62 {
63 	unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
64 		STATUSF_IP1 | STATUSF_IP0;
65 
66 	/* Set interrupt mask, but don't enable */
67 	change_c0_status(ST0_IM, imask);
68 }
69 
70 void bcm1480_smp_finish(void)
71 {
72 	extern void sb1480_clockevent_init(void);
73 
74 	sb1480_clockevent_init();
75 	local_irq_enable();
76 }
77 
78 /*
79  * These are routines for dealing with the sb1250 smp capabilities
80  * independent of board/firmware
81  */
82 
83 /*
84  * Simple enough; everything is set up, so just poke the appropriate mailbox
85  * register, and we should be set
86  */
87 void core_send_ipi(int cpu, unsigned int action)
88 {
89 	__raw_writeq((((u64)action)<< 48), mailbox_0_set_regs[cpu]);
90 }
91 
92 void bcm1480_mailbox_interrupt(void)
93 {
94 	int cpu = smp_processor_id();
95 	unsigned int action;
96 
97 	kstat_this_cpu.irqs[K_BCM1480_INT_MBOX_0_0]++;
98 	/* Load the mailbox register to figure out what we're supposed to do */
99 	action = (__raw_readq(mailbox_0_regs[cpu]) >> 48) & 0xffff;
100 
101 	/* Clear the mailbox to clear the interrupt */
102 	__raw_writeq(((u64)action)<<48, mailbox_0_clear_regs[cpu]);
103 
104 	/*
105 	 * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the
106 	 * interrupt will do the reschedule for us
107 	 */
108 
109 	if (action & SMP_CALL_FUNCTION)
110 		smp_call_function_interrupt();
111 }
112