xref: /linux/arch/powerpc/kernel/paca.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
1 /*
2  * c 2001 PPC 64 Team, IBM Corp
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
7  *      2 of the License, or (at your option) any later version.
8  */
9 
10 #include <linux/threads.h>
11 #include <linux/module.h>
12 
13 #include <asm/lppaca.h>
14 #include <asm/paca.h>
15 #include <asm/sections.h>
16 
17 /* This symbol is provided by the linker - let it fill in the paca
18  * field correctly */
19 extern unsigned long __toc_start;
20 
21 #ifdef CONFIG_PPC_BOOK3S
22 
23 /*
24  * The structure which the hypervisor knows about - this structure
25  * should not cross a page boundary.  The vpa_init/register_vpa call
26  * is now known to fail if the lppaca structure crosses a page
27  * boundary.  The lppaca is also used on legacy iSeries and POWER5
28  * pSeries boxes.  The lppaca is 640 bytes long, and cannot readily
29  * change since the hypervisor knows its layout, so a 1kB alignment
30  * will suffice to ensure that it doesn't cross a page boundary.
31  */
32 struct lppaca lppaca[] = {
33 	[0 ... (NR_CPUS-1)] = {
34 		.desc = 0xd397d781,	/* "LpPa" */
35 		.size = sizeof(struct lppaca),
36 		.dyn_proc_status = 2,
37 		.decr_val = 0x00ff0000,
38 		.fpregs_in_use = 1,
39 		.end_of_quantum = 0xfffffffffffffffful,
40 		.slb_count = 64,
41 		.vmxregs_in_use = 0,
42 		.page_ins = 0,
43 	},
44 };
45 
46 #endif /* CONFIG_PPC_BOOK3S */
47 
48 #ifdef CONFIG_PPC_STD_MMU_64
49 
50 /*
51  * 3 persistent SLBs are registered here.  The buffer will be zero
52  * initially, hence will all be invaild until we actually write them.
53  */
54 struct slb_shadow slb_shadow[] __cacheline_aligned = {
55 	[0 ... (NR_CPUS-1)] = {
56 		.persistent = SLB_NUM_BOLTED,
57 		.buffer_length = sizeof(struct slb_shadow),
58 	},
59 };
60 
61 #endif /* CONFIG_PPC_STD_MMU_64 */
62 
63 /* The Paca is an array with one entry per processor.  Each contains an
64  * lppaca, which contains the information shared between the
65  * hypervisor and Linux.
66  * On systems with hardware multi-threading, there are two threads
67  * per processor.  The Paca array must contain an entry for each thread.
68  * The VPD Areas will give a max logical processors = 2 * max physical
69  * processors.  The processor VPD array needs one entry per physical
70  * processor (not thread).
71  */
72 struct paca_struct paca[NR_CPUS];
73 EXPORT_SYMBOL(paca);
74 
75 void __init initialise_pacas(void)
76 {
77 	int cpu;
78 
79 	/* The TOC register (GPR2) points 32kB into the TOC, so that 64kB
80 	 * of the TOC can be addressed using a single machine instruction.
81 	 */
82 	unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL;
83 
84 	/* Can't use for_each_*_cpu, as they aren't functional yet */
85 	for (cpu = 0; cpu < NR_CPUS; cpu++) {
86 		struct paca_struct *new_paca = &paca[cpu];
87 
88 #ifdef CONFIG_PPC_BOOK3S
89 		new_paca->lppaca_ptr = &lppaca[cpu];
90 #endif
91 		new_paca->lock_token = 0x8000;
92 		new_paca->paca_index = cpu;
93 		new_paca->kernel_toc = kernel_toc;
94 		new_paca->kernelbase = (unsigned long) _stext;
95 		new_paca->kernel_msr = MSR_KERNEL;
96 		new_paca->hw_cpu_id = 0xffff;
97 		new_paca->__current = &init_task;
98 #ifdef CONFIG_PPC_STD_MMU_64
99 		new_paca->slb_shadow_ptr = &slb_shadow[cpu];
100 #endif /* CONFIG_PPC_STD_MMU_64 */
101 
102 	}
103 }
104