ARM: 6214/2: driver for the character LCD found in ARM refdesigns
[linux-2.6.git] / drivers / misc / sgi-xp / xp_sn2.c
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 Silicon Graphics, Inc.  All Rights Reserved.
7  */
8
9 /*
10  * Cross Partition (XP) sn2-based functions.
11  *
12  *      Architecture specific implementation of common functions.
13  */
14
15 #include <linux/module.h>
16 #include <linux/device.h>
17 #include <asm/sn/bte.h>
18 #include <asm/sn/sn_sal.h>
19 #include "xp.h"
20
21 /*
22  * The export of xp_nofault_PIOR needs to happen here since it is defined
23  * in drivers/misc/sgi-xp/xp_nofault.S. The target of the nofault read is
24  * defined here.
25  */
26 EXPORT_SYMBOL_GPL(xp_nofault_PIOR);
27
28 u64 xp_nofault_PIOR_target;
29 EXPORT_SYMBOL_GPL(xp_nofault_PIOR_target);
30
31 /*
32  * Register a nofault code region which performs a cross-partition PIO read.
33  * If the PIO read times out, the MCA handler will consume the error and
34  * return to a kernel-provided instruction to indicate an error. This PIO read
35  * exists because it is guaranteed to timeout if the destination is down
36  * (amo operations do not timeout on at least some CPUs on Shubs <= v1.2,
37  * which unfortunately we have to work around).
38  */
39 static enum xp_retval
40 xp_register_nofault_code_sn2(void)
41 {
42         int ret;
43         u64 func_addr;
44         u64 err_func_addr;
45
46         func_addr = *(u64 *)xp_nofault_PIOR;
47         err_func_addr = *(u64 *)xp_error_PIOR;
48         ret = sn_register_nofault_code(func_addr, err_func_addr, err_func_addr,
49                                        1, 1);
50         if (ret != 0) {
51                 dev_err(xp, "can't register nofault code, error=%d\n", ret);
52                 return xpSalError;
53         }
54         /*
55          * Setup the nofault PIO read target. (There is no special reason why
56          * SH_IPI_ACCESS was selected.)
57          */
58         if (is_shub1())
59                 xp_nofault_PIOR_target = SH1_IPI_ACCESS;
60         else if (is_shub2())
61                 xp_nofault_PIOR_target = SH2_IPI_ACCESS0;
62
63         return xpSuccess;
64 }
65
66 static void
67 xp_unregister_nofault_code_sn2(void)
68 {
69         u64 func_addr = *(u64 *)xp_nofault_PIOR;
70         u64 err_func_addr = *(u64 *)xp_error_PIOR;
71
72         /* unregister the PIO read nofault code region */
73         (void)sn_register_nofault_code(func_addr, err_func_addr,
74                                        err_func_addr, 1, 0);
75 }
76
77 /*
78  * Convert a virtual memory address to a physical memory address.
79  */
80 static unsigned long
81 xp_pa_sn2(void *addr)
82 {
83         return __pa(addr);
84 }
85
86 /*
87  * Convert a global physical to a socket physical address.
88  */
89 static unsigned long
90 xp_socket_pa_sn2(unsigned long gpa)
91 {
92         return gpa;
93 }
94
95 /*
96  * Wrapper for bte_copy().
97  *
98  *      dst_pa - physical address of the destination of the transfer.
99  *      src_pa - physical address of the source of the transfer.
100  *      len - number of bytes to transfer from source to destination.
101  *
102  * Note: xp_remote_memcpy_sn2() should never be called while holding a spinlock.
103  */
104 static enum xp_retval
105 xp_remote_memcpy_sn2(unsigned long dst_pa, const unsigned long src_pa,
106                      size_t len)
107 {
108         bte_result_t ret;
109
110         ret = bte_copy(src_pa, dst_pa, len, (BTE_NOTIFY | BTE_WACQUIRE), NULL);
111         if (ret == BTE_SUCCESS)
112                 return xpSuccess;
113
114         if (is_shub2()) {
115                 dev_err(xp, "bte_copy() on shub2 failed, error=0x%x dst_pa="
116                         "0x%016lx src_pa=0x%016lx len=%ld\\n", ret, dst_pa,
117                         src_pa, len);
118         } else {
119                 dev_err(xp, "bte_copy() failed, error=%d dst_pa=0x%016lx "
120                         "src_pa=0x%016lx len=%ld\\n", ret, dst_pa, src_pa, len);
121         }
122
123         return xpBteCopyError;
124 }
125
126 static int
127 xp_cpu_to_nasid_sn2(int cpuid)
128 {
129         return cpuid_to_nasid(cpuid);
130 }
131
132 static enum xp_retval
133 xp_expand_memprotect_sn2(unsigned long phys_addr, unsigned long size)
134 {
135         u64 nasid_array = 0;
136         int ret;
137
138         ret = sn_change_memprotect(phys_addr, size, SN_MEMPROT_ACCESS_CLASS_1,
139                                    &nasid_array);
140         if (ret != 0) {
141                 dev_err(xp, "sn_change_memprotect(,, "
142                         "SN_MEMPROT_ACCESS_CLASS_1,) failed ret=%d\n", ret);
143                 return xpSalError;
144         }
145         return xpSuccess;
146 }
147
148 static enum xp_retval
149 xp_restrict_memprotect_sn2(unsigned long phys_addr, unsigned long size)
150 {
151         u64 nasid_array = 0;
152         int ret;
153
154         ret = sn_change_memprotect(phys_addr, size, SN_MEMPROT_ACCESS_CLASS_0,
155                                    &nasid_array);
156         if (ret != 0) {
157                 dev_err(xp, "sn_change_memprotect(,, "
158                         "SN_MEMPROT_ACCESS_CLASS_0,) failed ret=%d\n", ret);
159                 return xpSalError;
160         }
161         return xpSuccess;
162 }
163
164 enum xp_retval
165 xp_init_sn2(void)
166 {
167         BUG_ON(!is_shub());
168
169         xp_max_npartitions = XP_MAX_NPARTITIONS_SN2;
170         xp_partition_id = sn_partition_id;
171         xp_region_size = sn_region_size;
172
173         xp_pa = xp_pa_sn2;
174         xp_socket_pa = xp_socket_pa_sn2;
175         xp_remote_memcpy = xp_remote_memcpy_sn2;
176         xp_cpu_to_nasid = xp_cpu_to_nasid_sn2;
177         xp_expand_memprotect = xp_expand_memprotect_sn2;
178         xp_restrict_memprotect = xp_restrict_memprotect_sn2;
179
180         return xp_register_nofault_code_sn2();
181 }
182
183 void
184 xp_exit_sn2(void)
185 {
186         BUG_ON(!is_shub());
187
188         xp_unregister_nofault_code_sn2();
189 }
190