1 /*
2 * SCLP early driver
3 *
4 * Copyright IBM Corp. 2013
5 */
6
7 #define KMSG_COMPONENT "sclp_early"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10 #include <linux/errno.h>
11 #include <asm/ctl_reg.h>
12 #include <asm/sclp.h>
13 #include <asm/ipl.h>
14 #include "sclp_sdias.h"
15 #include "sclp.h"
16
17 #define SCLP_CMDW_READ_SCP_INFO 0x00020001
18 #define SCLP_CMDW_READ_SCP_INFO_FORCED 0x00120001
19
20 struct read_info_sccb {
21 struct sccb_header header; /* 0-7 */
22 u16 rnmax; /* 8-9 */
23 u8 rnsize; /* 10 */
24 u8 _pad_11[16 - 11]; /* 11-15 */
25 u16 ncpurl; /* 16-17 */
26 u16 cpuoff; /* 18-19 */
27 u8 _pad_20[24 - 20]; /* 20-23 */
28 u8 loadparm[8]; /* 24-31 */
29 u8 _pad_32[42 - 32]; /* 32-41 */
30 u8 fac42; /* 42 */
31 u8 fac43; /* 43 */
32 u8 _pad_44[48 - 44]; /* 44-47 */
33 u64 facilities; /* 48-55 */
34 u8 _pad_56[66 - 56]; /* 56-65 */
35 u8 fac66; /* 66 */
36 u8 _pad_67[76 - 67]; /* 67-83 */
37 u32 ibc; /* 76-79 */
38 u8 _pad80[84 - 80]; /* 80-83 */
39 u8 fac84; /* 84 */
40 u8 fac85; /* 85 */
41 u8 _pad_86[91 - 86]; /* 86-90 */
42 u8 flags; /* 91 */
43 u8 _pad_92[100 - 92]; /* 92-99 */
44 u32 rnsize2; /* 100-103 */
45 u64 rnmax2; /* 104-111 */
46 u8 _pad_112[120 - 112]; /* 112-119 */
47 u16 hcpua; /* 120-121 */
48 u8 _pad_122[4096 - 122]; /* 122-4095 */
49 } __packed __aligned(PAGE_SIZE);
50
51 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
52 static struct sclp_ipl_info sclp_ipl_info;
53
54 struct sclp_info sclp;
55 EXPORT_SYMBOL(sclp);
56
sclp_cmd_sync_early(sclp_cmdw_t cmd,void * sccb)57 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
58 {
59 int rc;
60
61 __ctl_set_bit(0, 9);
62 rc = sclp_service_call(cmd, sccb);
63 if (rc)
64 goto out;
65 __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
66 PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
67 local_irq_disable();
68 out:
69 /* Contents of the sccb might have changed. */
70 barrier();
71 __ctl_clear_bit(0, 9);
72 return rc;
73 }
74
sclp_read_info_early(struct read_info_sccb * sccb)75 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
76 {
77 int rc, i;
78 sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
79 SCLP_CMDW_READ_SCP_INFO};
80
81 for (i = 0; i < ARRAY_SIZE(commands); i++) {
82 do {
83 memset(sccb, 0, sizeof(*sccb));
84 sccb->header.length = sizeof(*sccb);
85 sccb->header.function_code = 0x80;
86 sccb->header.control_mask[2] = 0x80;
87 rc = sclp_cmd_sync_early(commands[i], sccb);
88 } while (rc == -EBUSY);
89
90 if (rc)
91 break;
92 if (sccb->header.response_code == 0x10)
93 return 0;
94 if (sccb->header.response_code != 0x1f0)
95 break;
96 }
97 return -EIO;
98 }
99
sclp_facilities_detect(struct read_info_sccb * sccb)100 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
101 {
102 struct sclp_core_entry *cpue;
103 u16 boot_cpu_address, cpu;
104
105 if (sclp_read_info_early(sccb))
106 return;
107
108 sclp.facilities = sccb->facilities;
109 sclp.has_sprp = !!(sccb->fac84 & 0x02);
110 sclp.has_core_type = !!(sccb->fac84 & 0x01);
111 if (sccb->fac85 & 0x02)
112 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
113 sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
114 sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
115 sclp.rzm <<= 20;
116 sclp.ibc = sccb->ibc;
117
118 if (!sccb->hcpua) {
119 if (MACHINE_IS_VM)
120 sclp.max_cores = 64;
121 else
122 sclp.max_cores = sccb->ncpurl;
123 } else {
124 sclp.max_cores = sccb->hcpua + 1;
125 }
126
127 boot_cpu_address = stap();
128 cpue = (void *)sccb + sccb->cpuoff;
129 for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
130 if (boot_cpu_address != cpue->core_id)
131 continue;
132 sclp.has_siif = cpue->siif;
133 sclp.has_sigpif = cpue->sigpif;
134 break;
135 }
136
137 /* Save IPL information */
138 sclp_ipl_info.is_valid = 1;
139 if (sccb->flags & 0x2)
140 sclp_ipl_info.has_dump = 1;
141 memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
142
143 sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
144 sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
145 sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
146 }
147
148 /*
149 * This function will be called after sclp_facilities_detect(), which gets
150 * called from early.c code. The sclp_facilities_detect() function retrieves
151 * and saves the IPL information.
152 */
sclp_get_ipl_info(struct sclp_ipl_info * info)153 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
154 {
155 *info = sclp_ipl_info;
156 }
157
sclp_cmd_early(sclp_cmdw_t cmd,void * sccb)158 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
159 {
160 int rc;
161
162 do {
163 rc = sclp_cmd_sync_early(cmd, sccb);
164 } while (rc == -EBUSY);
165
166 if (rc)
167 return -EIO;
168 if (((struct sccb_header *) sccb)->response_code != 0x0020)
169 return -EIO;
170 return 0;
171 }
172
sccb_init_eq_size(struct sdias_sccb * sccb)173 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
174 {
175 memset(sccb, 0, sizeof(*sccb));
176
177 sccb->hdr.length = sizeof(*sccb);
178 sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
179 sccb->evbuf.hdr.type = EVTYP_SDIAS;
180 sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
181 sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
182 sccb->evbuf.event_id = 4712;
183 sccb->evbuf.dbs = 1;
184 }
185
sclp_set_event_mask(struct init_sccb * sccb,unsigned long receive_mask,unsigned long send_mask)186 static int __init sclp_set_event_mask(struct init_sccb *sccb,
187 unsigned long receive_mask,
188 unsigned long send_mask)
189 {
190 memset(sccb, 0, sizeof(*sccb));
191 sccb->header.length = sizeof(*sccb);
192 sccb->mask_length = sizeof(sccb_mask_t);
193 sccb->receive_mask = receive_mask;
194 sccb->send_mask = send_mask;
195 return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
196 }
197
sclp_hsa_size_init(struct sdias_sccb * sccb)198 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
199 {
200 sccb_init_eq_size(sccb);
201 if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
202 return -EIO;
203 if (sccb->evbuf.blk_cnt == 0)
204 return 0;
205 return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
206 }
207
sclp_hsa_copy_wait(struct sccb_header * sccb)208 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
209 {
210 memset(sccb, 0, PAGE_SIZE);
211 sccb->length = PAGE_SIZE;
212 if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
213 return -EIO;
214 if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
215 return 0;
216 return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
217 }
218
sclp_hsa_size_detect(void * sccb)219 static void __init sclp_hsa_size_detect(void *sccb)
220 {
221 long size;
222
223 /* First try synchronous interface (LPAR) */
224 if (sclp_set_event_mask(sccb, 0, 0x40000010))
225 return;
226 size = sclp_hsa_size_init(sccb);
227 if (size < 0)
228 return;
229 if (size != 0)
230 goto out;
231 /* Then try asynchronous interface (z/VM) */
232 if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
233 return;
234 size = sclp_hsa_size_init(sccb);
235 if (size < 0)
236 return;
237 size = sclp_hsa_copy_wait(sccb);
238 if (size < 0)
239 return;
240 out:
241 sclp.hsa_size = size;
242 }
243
sclp_con_check_linemode(struct init_sccb * sccb)244 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
245 {
246 if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
247 return 0;
248 if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
249 return 0;
250 return 1;
251 }
252
sclp_console_detect(struct init_sccb * sccb)253 static void __init sclp_console_detect(struct init_sccb *sccb)
254 {
255 if (sccb->header.response_code != 0x20)
256 return;
257
258 if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
259 sclp.has_vt220 = 1;
260
261 if (sclp_con_check_linemode(sccb))
262 sclp.has_linemode = 1;
263 }
264
sclp_early_detect(void)265 void __init sclp_early_detect(void)
266 {
267 void *sccb = &sccb_early;
268
269 sclp_facilities_detect(sccb);
270 sclp_hsa_size_detect(sccb);
271
272 /* Turn off SCLP event notifications. Also save remote masks in the
273 * sccb. These are sufficient to detect sclp console capabilities.
274 */
275 sclp_set_event_mask(sccb, 0, 0);
276 sclp_console_detect(sccb);
277 }
278