xref: /openbmc/linux/drivers/s390/char/sclp_early.c (revision dfe94d40)
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 <linux/memblock.h>
13 #include <asm/ctl_reg.h>
14 #include <asm/sclp.h>
15 #include <asm/ipl.h>
16 #include <asm/setup.h>
17 #include <asm/facility.h>
18 #include "sclp_sdias.h"
19 #include "sclp.h"
20 
21 static struct sclp_ipl_info sclp_ipl_info;
22 
23 struct sclp_info sclp;
24 EXPORT_SYMBOL(sclp);
25 
26 static void __init sclp_early_facilities_detect(void)
27 {
28 	struct sclp_core_entry *cpue;
29 	struct read_info_sccb *sccb;
30 	u16 boot_cpu_address, cpu;
31 
32 	sccb = sclp_early_get_info();
33 	if (!sccb)
34 		return;
35 
36 	sclp.facilities = sccb->facilities;
37 	sclp.has_sprp = !!(sccb->fac84 & 0x02);
38 	sclp.has_core_type = !!(sccb->fac84 & 0x01);
39 	sclp.has_gsls = !!(sccb->fac85 & 0x80);
40 	sclp.has_64bscao = !!(sccb->fac116 & 0x80);
41 	sclp.has_cmma = !!(sccb->fac116 & 0x40);
42 	sclp.has_esca = !!(sccb->fac116 & 0x08);
43 	sclp.has_pfmfi = !!(sccb->fac117 & 0x40);
44 	sclp.has_ibs = !!(sccb->fac117 & 0x20);
45 	sclp.has_gisaf = !!(sccb->fac118 & 0x08);
46 	sclp.has_hvs = !!(sccb->fac119 & 0x80);
47 	sclp.has_kss = !!(sccb->fac98 & 0x01);
48 	sclp.has_sipl = !!(sccb->cbl & 0x4000);
49 	if (sccb->fac85 & 0x02)
50 		S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
51 	if (sccb->fac91 & 0x40)
52 		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_GUEST;
53 	if (sccb->cpuoff > 134)
54 		sclp.has_diag318 = !!(sccb->byte_134 & 0x80);
55 	sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
56 	sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
57 	sclp.rzm <<= 20;
58 	sclp.ibc = sccb->ibc;
59 
60 	if (sccb->hamaxpow && sccb->hamaxpow < 64)
61 		sclp.hamax = (1UL << sccb->hamaxpow) - 1;
62 	else
63 		sclp.hamax = U64_MAX;
64 
65 	if (!sccb->hcpua) {
66 		if (MACHINE_IS_VM)
67 			sclp.max_cores = 64;
68 		else
69 			sclp.max_cores = sccb->ncpurl;
70 	} else {
71 		sclp.max_cores = sccb->hcpua + 1;
72 	}
73 
74 	boot_cpu_address = stap();
75 	cpue = (void *)sccb + sccb->cpuoff;
76 	for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
77 		if (boot_cpu_address != cpue->core_id)
78 			continue;
79 		sclp.has_siif = cpue->siif;
80 		sclp.has_sigpif = cpue->sigpif;
81 		sclp.has_sief2 = cpue->sief2;
82 		sclp.has_gpere = cpue->gpere;
83 		sclp.has_ib = cpue->ib;
84 		sclp.has_cei = cpue->cei;
85 		sclp.has_skey = cpue->skey;
86 		break;
87 	}
88 
89 	/* Save IPL information */
90 	sclp_ipl_info.is_valid = 1;
91 	if (sccb->fac91 & 0x2)
92 		sclp_ipl_info.has_dump = 1;
93 	memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
94 
95 	if (sccb->hsa_size)
96 		sclp.hsa_size = (sccb->hsa_size - 1) * PAGE_SIZE;
97 	sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
98 	sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
99 	sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
100 
101 	sclp.hmfai = sccb->hmfai;
102 	sclp.has_dirq = !!(sccb->cpudirq & 0x80);
103 }
104 
105 /*
106  * This function will be called after sclp_early_facilities_detect(), which gets
107  * called from early.c code. The sclp_early_facilities_detect() function retrieves
108  * and saves the IPL information.
109  */
110 void __init sclp_early_get_ipl_info(struct sclp_ipl_info *info)
111 {
112 	*info = sclp_ipl_info;
113 }
114 
115 int __init sclp_early_get_core_info(struct sclp_core_info *info)
116 {
117 	struct read_cpu_info_sccb *sccb;
118 	int length = test_facility(140) ? EXT_SCCB_READ_CPU : PAGE_SIZE;
119 	int rc = 0;
120 
121 	if (!SCLP_HAS_CPU_INFO)
122 		return -EOPNOTSUPP;
123 
124 	sccb = memblock_alloc_low(length, PAGE_SIZE);
125 	if (!sccb)
126 		return -ENOMEM;
127 
128 	memset(sccb, 0, length);
129 	sccb->header.length = length;
130 	sccb->header.control_mask[2] = 0x80;
131 	if (sclp_early_cmd(SCLP_CMDW_READ_CPU_INFO, sccb)) {
132 		rc = -EIO;
133 		goto out;
134 	}
135 	if (sccb->header.response_code != 0x0010) {
136 		rc = -EIO;
137 		goto out;
138 	}
139 	sclp_fill_core_info(info, sccb);
140 out:
141 	memblock_free_early((unsigned long)sccb, length);
142 	return rc;
143 }
144 
145 static void __init sclp_early_console_detect(struct init_sccb *sccb)
146 {
147 	if (sccb->header.response_code != 0x20)
148 		return;
149 
150 	if (sclp_early_con_check_vt220(sccb))
151 		sclp.has_vt220 = 1;
152 
153 	if (sclp_early_con_check_linemode(sccb))
154 		sclp.has_linemode = 1;
155 }
156 
157 void __init sclp_early_detect(void)
158 {
159 	void *sccb = sclp_early_sccb;
160 
161 	sclp_early_facilities_detect();
162 
163 	/*
164 	 * Turn off SCLP event notifications.  Also save remote masks in the
165 	 * sccb.  These are sufficient to detect sclp console capabilities.
166 	 */
167 	sclp_early_set_event_mask(sccb, 0, 0);
168 	sclp_early_console_detect(sccb);
169 }
170