1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SCLP early driver
4  *
5  * Copyright IBM Corp. 2013
6  */
7 
8 #define KMSG_COMPONENT "sclp_early"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/errno.h>
12 #include <asm/ctl_reg.h>
13 #include <asm/sclp.h>
14 #include <asm/ipl.h>
15 #include "sclp_sdias.h"
16 #include "sclp.h"
17 
18 #define SCLP_CMDW_READ_SCP_INFO		0x00020001
19 #define SCLP_CMDW_READ_SCP_INFO_FORCED	0x00120001
20 
21 struct read_info_sccb {
22 	struct	sccb_header header;	/* 0-7 */
23 	u16	rnmax;			/* 8-9 */
24 	u8	rnsize;			/* 10 */
25 	u8	_pad_11[16 - 11];	/* 11-15 */
26 	u16	ncpurl;			/* 16-17 */
27 	u16	cpuoff;			/* 18-19 */
28 	u8	_pad_20[24 - 20];	/* 20-23 */
29 	u8	loadparm[8];		/* 24-31 */
30 	u8	_pad_32[42 - 32];	/* 32-41 */
31 	u8	fac42;			/* 42 */
32 	u8	fac43;			/* 43 */
33 	u8	_pad_44[48 - 44];	/* 44-47 */
34 	u64	facilities;		/* 48-55 */
35 	u8	_pad_56[66 - 56];	/* 56-65 */
36 	u8	fac66;			/* 66 */
37 	u8	_pad_67[76 - 67];	/* 67-83 */
38 	u32	ibc;			/* 76-79 */
39 	u8	_pad80[84 - 80];	/* 80-83 */
40 	u8	fac84;			/* 84 */
41 	u8	fac85;			/* 85 */
42 	u8	_pad_86[91 - 86];	/* 86-90 */
43 	u8	fac91;			/* 91 */
44 	u8	_pad_92[98 - 92];	/* 92-97 */
45 	u8	fac98;			/* 98 */
46 	u8	hamaxpow;		/* 99 */
47 	u32	rnsize2;		/* 100-103 */
48 	u64	rnmax2;			/* 104-111 */
49 	u8	_pad_112[116 - 112];	/* 112-115 */
50 	u8	fac116;			/* 116 */
51 	u8	fac117;			/* 117 */
52 	u8	fac118;			/* 118 */
53 	u8	fac119;			/* 119 */
54 	u16	hcpua;			/* 120-121 */
55 	u8	_pad_122[124 - 122];	/* 122-123 */
56 	u32	hmfai;			/* 124-127 */
57 	u8	_pad_128[4096 - 128];	/* 128-4095 */
58 } __packed __aligned(PAGE_SIZE);
59 
60 static struct sclp_ipl_info sclp_ipl_info;
61 
62 struct sclp_info sclp;
63 EXPORT_SYMBOL(sclp);
64 
sclp_early_read_info(struct read_info_sccb * sccb)65 static int __init sclp_early_read_info(struct read_info_sccb *sccb)
66 {
67 	int i;
68 	sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
69 				  SCLP_CMDW_READ_SCP_INFO};
70 
71 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
72 		memset(sccb, 0, sizeof(*sccb));
73 		sccb->header.length = sizeof(*sccb);
74 		sccb->header.function_code = 0x80;
75 		sccb->header.control_mask[2] = 0x80;
76 		if (sclp_early_cmd(commands[i], sccb))
77 			break;
78 		if (sccb->header.response_code == 0x10)
79 			return 0;
80 		if (sccb->header.response_code != 0x1f0)
81 			break;
82 	}
83 	return -EIO;
84 }
85 
sclp_early_facilities_detect(struct read_info_sccb * sccb)86 static void __init sclp_early_facilities_detect(struct read_info_sccb *sccb)
87 {
88 	struct sclp_core_entry *cpue;
89 	u16 boot_cpu_address, cpu;
90 
91 	if (sclp_early_read_info(sccb))
92 		return;
93 
94 	sclp.facilities = sccb->facilities;
95 	sclp.has_sprp = !!(sccb->fac84 & 0x02);
96 	sclp.has_core_type = !!(sccb->fac84 & 0x01);
97 	sclp.has_gsls = !!(sccb->fac85 & 0x80);
98 	sclp.has_64bscao = !!(sccb->fac116 & 0x80);
99 	sclp.has_cmma = !!(sccb->fac116 & 0x40);
100 	sclp.has_esca = !!(sccb->fac116 & 0x08);
101 	sclp.has_pfmfi = !!(sccb->fac117 & 0x40);
102 	sclp.has_ibs = !!(sccb->fac117 & 0x20);
103 	sclp.has_gisaf = !!(sccb->fac118 & 0x08);
104 	sclp.has_hvs = !!(sccb->fac119 & 0x80);
105 	sclp.has_kss = !!(sccb->fac98 & 0x01);
106 	if (sccb->fac85 & 0x02)
107 		S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
108 	if (sccb->fac91 & 0x40)
109 		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_GUEST;
110 	sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
111 	sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
112 	sclp.rzm <<= 20;
113 	sclp.ibc = sccb->ibc;
114 
115 	if (sccb->hamaxpow && sccb->hamaxpow < 64)
116 		sclp.hamax = (1UL << sccb->hamaxpow) - 1;
117 	else
118 		sclp.hamax = U64_MAX;
119 
120 	if (!sccb->hcpua) {
121 		if (MACHINE_IS_VM)
122 			sclp.max_cores = 64;
123 		else
124 			sclp.max_cores = sccb->ncpurl;
125 	} else {
126 		sclp.max_cores = sccb->hcpua + 1;
127 	}
128 
129 	boot_cpu_address = stap();
130 	cpue = (void *)sccb + sccb->cpuoff;
131 	for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
132 		if (boot_cpu_address != cpue->core_id)
133 			continue;
134 		sclp.has_siif = cpue->siif;
135 		sclp.has_sigpif = cpue->sigpif;
136 		sclp.has_sief2 = cpue->sief2;
137 		sclp.has_gpere = cpue->gpere;
138 		sclp.has_ib = cpue->ib;
139 		sclp.has_cei = cpue->cei;
140 		sclp.has_skey = cpue->skey;
141 		break;
142 	}
143 
144 	/* Save IPL information */
145 	sclp_ipl_info.is_valid = 1;
146 	if (sccb->fac91 & 0x2)
147 		sclp_ipl_info.has_dump = 1;
148 	memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
149 
150 	sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
151 	sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
152 	sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
153 
154 	sclp.hmfai = sccb->hmfai;
155 }
156 
157 /*
158  * This function will be called after sclp_early_facilities_detect(), which gets
159  * called from early.c code. The sclp_early_facilities_detect() function retrieves
160  * and saves the IPL information.
161  */
sclp_early_get_ipl_info(struct sclp_ipl_info * info)162 void __init sclp_early_get_ipl_info(struct sclp_ipl_info *info)
163 {
164 	*info = sclp_ipl_info;
165 }
166 
167 static struct sclp_core_info sclp_early_core_info __initdata;
168 static int sclp_early_core_info_valid __initdata;
169 
sclp_early_init_core_info(struct read_cpu_info_sccb * sccb)170 static void __init sclp_early_init_core_info(struct read_cpu_info_sccb *sccb)
171 {
172 	if (!SCLP_HAS_CPU_INFO)
173 		return;
174 	memset(sccb, 0, sizeof(*sccb));
175 	sccb->header.length = sizeof(*sccb);
176 	if (sclp_early_cmd(SCLP_CMDW_READ_CPU_INFO, sccb))
177 		return;
178 	if (sccb->header.response_code != 0x0010)
179 		return;
180 	sclp_fill_core_info(&sclp_early_core_info, sccb);
181 	sclp_early_core_info_valid = 1;
182 }
183 
sclp_early_get_core_info(struct sclp_core_info * info)184 int __init sclp_early_get_core_info(struct sclp_core_info *info)
185 {
186 	if (!sclp_early_core_info_valid)
187 		return -EIO;
188 	*info = sclp_early_core_info;
189 	return 0;
190 }
191 
sclp_early_hsa_size_init(struct sdias_sccb * sccb)192 static long __init sclp_early_hsa_size_init(struct sdias_sccb *sccb)
193 {
194 	memset(sccb, 0, sizeof(*sccb));
195 	sccb->hdr.length = sizeof(*sccb);
196 	sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
197 	sccb->evbuf.hdr.type = EVTYP_SDIAS;
198 	sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
199 	sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
200 	sccb->evbuf.event_id = 4712;
201 	sccb->evbuf.dbs = 1;
202 	if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
203 		return -EIO;
204 	if (sccb->hdr.response_code != 0x20)
205 		return -EIO;
206 	if (sccb->evbuf.blk_cnt == 0)
207 		return 0;
208 	return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
209 }
210 
sclp_early_hsa_copy_wait(struct sdias_sccb * sccb)211 static long __init sclp_early_hsa_copy_wait(struct sdias_sccb *sccb)
212 {
213 	memset(sccb, 0, PAGE_SIZE);
214 	sccb->hdr.length = PAGE_SIZE;
215 	if (sclp_early_cmd(SCLP_CMDW_READ_EVENT_DATA, sccb))
216 		return -EIO;
217 	if ((sccb->hdr.response_code != 0x20) && (sccb->hdr.response_code != 0x220))
218 		return -EIO;
219 	if (sccb->evbuf.blk_cnt == 0)
220 		return 0;
221 	return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
222 }
223 
sclp_early_hsa_size_detect(void * sccb)224 static void __init sclp_early_hsa_size_detect(void *sccb)
225 {
226 	unsigned long flags;
227 	long size = -EIO;
228 
229 	raw_local_irq_save(flags);
230 	if (sclp_early_set_event_mask(sccb, EVTYP_SDIAS_MASK, EVTYP_SDIAS_MASK))
231 		goto out;
232 	size = sclp_early_hsa_size_init(sccb);
233 	/* First check for synchronous response (LPAR) */
234 	if (size)
235 		goto out_mask;
236 	if (!(S390_lowcore.ext_params & 1))
237 		sclp_early_wait_irq();
238 	size = sclp_early_hsa_copy_wait(sccb);
239 out_mask:
240 	sclp_early_set_event_mask(sccb, 0, 0);
241 out:
242 	raw_local_irq_restore(flags);
243 	if (size > 0)
244 		sclp.hsa_size = size;
245 }
246 
sclp_early_console_detect(struct init_sccb * sccb)247 static void __init sclp_early_console_detect(struct init_sccb *sccb)
248 {
249 	if (sccb->header.response_code != 0x20)
250 		return;
251 
252 	if (sclp_early_con_check_vt220(sccb))
253 		sclp.has_vt220 = 1;
254 
255 	if (sclp_early_con_check_linemode(sccb))
256 		sclp.has_linemode = 1;
257 }
258 
sclp_early_detect(void)259 void __init sclp_early_detect(void)
260 {
261 	void *sccb = &sclp_early_sccb;
262 
263 	sclp_early_facilities_detect(sccb);
264 	sclp_early_init_core_info(sccb);
265 	sclp_early_hsa_size_detect(sccb);
266 
267 	/*
268 	 * Turn off SCLP event notifications.  Also save remote masks in the
269 	 * sccb.  These are sufficient to detect sclp console capabilities.
270 	 */
271 	sclp_early_set_event_mask(sccb, 0, 0);
272 	sclp_early_console_detect(sccb);
273 }
274