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