linux_dsm_epyc7002/drivers/s390/char/sclp_early.c
Gerald Schaefer 087c4d7423 s390/sclp: do not use static sccbs
The sccbs for init/read/sdias/early have to be located below 2 GB, and
they are currently defined as a static buffer.

With a relocatable kernel that could reside at any place in memory, this
will no longer guarantee the location below 2 GB, so use a dynamic
GFP_DMA allocation instead.

The sclp_early_sccb buffer needs special handling, as it can be used
very early, and by both the decompressor and also the decompressed
kernel. Therefore, a fixed 4 KB buffer is introduced at 0x11000, the
former PARMAREA_END. The new PARMAREA_END is now 0x12000, and it is
renamed to HEAD_END, as it is rather the end of head.S and not the end
of the parmarea.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29 10:47:10 +02:00

162 lines
4.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SCLP early driver
*
* Copyright IBM Corp. 2013
*/
#define KMSG_COMPONENT "sclp_early"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/errno.h>
#include <asm/ctl_reg.h>
#include <asm/sclp.h>
#include <asm/ipl.h>
#include "sclp_sdias.h"
#include "sclp.h"
static struct sclp_ipl_info sclp_ipl_info;
struct sclp_info sclp;
EXPORT_SYMBOL(sclp);
static void __init sclp_early_facilities_detect(struct read_info_sccb *sccb)
{
struct sclp_core_entry *cpue;
u16 boot_cpu_address, cpu;
if (sclp_early_get_info(sccb))
return;
sclp.facilities = sccb->facilities;
sclp.has_sprp = !!(sccb->fac84 & 0x02);
sclp.has_core_type = !!(sccb->fac84 & 0x01);
sclp.has_gsls = !!(sccb->fac85 & 0x80);
sclp.has_64bscao = !!(sccb->fac116 & 0x80);
sclp.has_cmma = !!(sccb->fac116 & 0x40);
sclp.has_esca = !!(sccb->fac116 & 0x08);
sclp.has_pfmfi = !!(sccb->fac117 & 0x40);
sclp.has_ibs = !!(sccb->fac117 & 0x20);
sclp.has_gisaf = !!(sccb->fac118 & 0x08);
sclp.has_hvs = !!(sccb->fac119 & 0x80);
sclp.has_kss = !!(sccb->fac98 & 0x01);
sclp.has_sipl = !!(sccb->cbl & 0x02);
sclp.has_sipl_g2 = !!(sccb->cbl & 0x04);
if (sccb->fac85 & 0x02)
S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
if (sccb->fac91 & 0x40)
S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_GUEST;
if (sccb->cpuoff > 134)
sclp.has_diag318 = !!(sccb->byte_134 & 0x80);
sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
sclp.rzm <<= 20;
sclp.ibc = sccb->ibc;
if (sccb->hamaxpow && sccb->hamaxpow < 64)
sclp.hamax = (1UL << sccb->hamaxpow) - 1;
else
sclp.hamax = U64_MAX;
if (!sccb->hcpua) {
if (MACHINE_IS_VM)
sclp.max_cores = 64;
else
sclp.max_cores = sccb->ncpurl;
} else {
sclp.max_cores = sccb->hcpua + 1;
}
boot_cpu_address = stap();
cpue = (void *)sccb + sccb->cpuoff;
for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
if (boot_cpu_address != cpue->core_id)
continue;
sclp.has_siif = cpue->siif;
sclp.has_sigpif = cpue->sigpif;
sclp.has_sief2 = cpue->sief2;
sclp.has_gpere = cpue->gpere;
sclp.has_ib = cpue->ib;
sclp.has_cei = cpue->cei;
sclp.has_skey = cpue->skey;
break;
}
/* Save IPL information */
sclp_ipl_info.is_valid = 1;
if (sccb->fac91 & 0x2)
sclp_ipl_info.has_dump = 1;
memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
if (sccb->hsa_size)
sclp.hsa_size = (sccb->hsa_size - 1) * PAGE_SIZE;
sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
sclp.hmfai = sccb->hmfai;
sclp.has_dirq = !!(sccb->cpudirq & 0x80);
}
/*
* This function will be called after sclp_early_facilities_detect(), which gets
* called from early.c code. The sclp_early_facilities_detect() function retrieves
* and saves the IPL information.
*/
void __init sclp_early_get_ipl_info(struct sclp_ipl_info *info)
{
*info = sclp_ipl_info;
}
static struct sclp_core_info sclp_early_core_info __initdata;
static int sclp_early_core_info_valid __initdata;
static void __init sclp_early_init_core_info(struct read_cpu_info_sccb *sccb)
{
if (!SCLP_HAS_CPU_INFO)
return;
memset(sccb, 0, sizeof(*sccb));
sccb->header.length = sizeof(*sccb);
if (sclp_early_cmd(SCLP_CMDW_READ_CPU_INFO, sccb))
return;
if (sccb->header.response_code != 0x0010)
return;
sclp_fill_core_info(&sclp_early_core_info, sccb);
sclp_early_core_info_valid = 1;
}
int __init sclp_early_get_core_info(struct sclp_core_info *info)
{
if (!sclp_early_core_info_valid)
return -EIO;
*info = sclp_early_core_info;
return 0;
}
static void __init sclp_early_console_detect(struct init_sccb *sccb)
{
if (sccb->header.response_code != 0x20)
return;
if (sclp_early_con_check_vt220(sccb))
sclp.has_vt220 = 1;
if (sclp_early_con_check_linemode(sccb))
sclp.has_linemode = 1;
}
void __init sclp_early_detect(void)
{
void *sccb = sclp_early_sccb;
sclp_early_facilities_detect(sccb);
sclp_early_init_core_info(sccb);
/*
* Turn off SCLP event notifications. Also save remote masks in the
* sccb. These are sufficient to detect sclp console capabilities.
*/
sclp_early_set_event_mask(sccb, 0, 0);
sclp_early_console_detect(sccb);
}