linux-hardened/drivers/s390/char/sclp_early.c
Martin Schwidefsky 10ad34bc76 s390: add SMT support
The multi-threading facility is introduced with the z13 processor family.
This patch adds code to detect the multi-threading facility. With the
facility enabled each core will surface multiple hardware threads to the
system. Each hardware threads looks like a normal CPU to the operating
system with all its registers and properties.

The SCLP interface reports the SMT topology indirectly via the maximum
thread id. Each reported CPU in the result of a read-scp-information
is a core representing a number of hardware threads.

To reflect the reduced CPU capacity if two hardware threads run on a
single core the MT utilization counter set is used to normalize the
raw cputime obtained by the CPU timer deltas. This scaled cputime is
reported via the taskstats interface. The normal /proc/stat numbers
are based on the raw cputime and are not affected by the normalization.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-01-22 12:16:01 +01:00

344 lines
7.9 KiB
C

/*
* SCLP early driver
*
* Copyright IBM Corp. 2013
*/
#define KMSG_COMPONENT "sclp_early"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <asm/ctl_reg.h>
#include <asm/sclp.h>
#include <asm/ipl.h>
#include "sclp_sdias.h"
#include "sclp.h"
#define SCLP_CMDW_READ_SCP_INFO 0x00020001
#define SCLP_CMDW_READ_SCP_INFO_FORCED 0x00120001
struct read_info_sccb {
struct sccb_header header; /* 0-7 */
u16 rnmax; /* 8-9 */
u8 rnsize; /* 10 */
u8 _pad_11[16 - 11]; /* 11-15 */
u16 ncpurl; /* 16-17 */
u16 cpuoff; /* 18-19 */
u8 _pad_20[24 - 20]; /* 20-23 */
u8 loadparm[8]; /* 24-31 */
u8 _pad_32[42 - 32]; /* 32-41 */
u8 fac42; /* 42 */
u8 fac43; /* 43 */
u8 _pad_44[48 - 44]; /* 44-47 */
u64 facilities; /* 48-55 */
u8 _pad_56[66 - 56]; /* 56-65 */
u8 fac66; /* 66 */
u8 _pad_67[76 - 67]; /* 67-83 */
u32 ibc; /* 76-79 */
u8 _pad80[84 - 80]; /* 80-83 */
u8 fac84; /* 84 */
u8 fac85; /* 85 */
u8 _pad_86[91 - 86]; /* 86-90 */
u8 flags; /* 91 */
u8 _pad_92[100 - 92]; /* 92-99 */
u32 rnsize2; /* 100-103 */
u64 rnmax2; /* 104-111 */
u8 _pad_112[120 - 112]; /* 112-119 */
u16 hcpua; /* 120-121 */
u8 _pad_122[4096 - 122]; /* 122-4095 */
} __packed __aligned(PAGE_SIZE);
static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
static unsigned int sclp_con_has_vt220 __initdata;
static unsigned int sclp_con_has_linemode __initdata;
static unsigned long sclp_hsa_size;
static unsigned int sclp_max_cpu;
static struct sclp_ipl_info sclp_ipl_info;
static unsigned char sclp_siif;
static u32 sclp_ibc;
static unsigned int sclp_mtid;
static unsigned int sclp_mtid_cp;
static unsigned int sclp_mtid_max;
static unsigned int sclp_mtid_prev;
u64 sclp_facilities;
u8 sclp_fac84;
unsigned long long sclp_rzm;
unsigned long long sclp_rnmax;
static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
{
int rc;
__ctl_set_bit(0, 9);
rc = sclp_service_call(cmd, sccb);
if (rc)
goto out;
__load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
local_irq_disable();
out:
/* Contents of the sccb might have changed. */
barrier();
__ctl_clear_bit(0, 9);
return rc;
}
static int __init sclp_read_info_early(struct read_info_sccb *sccb)
{
int rc, i;
sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
SCLP_CMDW_READ_SCP_INFO};
for (i = 0; i < ARRAY_SIZE(commands); i++) {
do {
memset(sccb, 0, sizeof(*sccb));
sccb->header.length = sizeof(*sccb);
sccb->header.function_code = 0x80;
sccb->header.control_mask[2] = 0x80;
rc = sclp_cmd_sync_early(commands[i], sccb);
} while (rc == -EBUSY);
if (rc)
break;
if (sccb->header.response_code == 0x10)
return 0;
if (sccb->header.response_code != 0x1f0)
break;
}
return -EIO;
}
static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
{
struct sclp_cpu_entry *cpue;
u16 boot_cpu_address, cpu;
if (sclp_read_info_early(sccb))
return;
sclp_facilities = sccb->facilities;
sclp_fac84 = sccb->fac84;
if (sccb->fac85 & 0x02)
S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
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->hcpua) {
if (MACHINE_IS_VM)
sclp_max_cpu = 64;
else
sclp_max_cpu = sccb->ncpurl;
} else {
sclp_max_cpu = 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_siif = cpue->siif;
break;
}
/* Save IPL information */
sclp_ipl_info.is_valid = 1;
if (sccb->flags & 0x2)
sclp_ipl_info.has_dump = 1;
memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
sclp_mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
sclp_mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
sclp_mtid_max = max(sclp_mtid, sclp_mtid_cp);
sclp_mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
}
bool __init sclp_has_linemode(void)
{
return !!sclp_con_has_linemode;
}
bool __init sclp_has_vt220(void)
{
return !!sclp_con_has_vt220;
}
unsigned long long sclp_get_rnmax(void)
{
return sclp_rnmax;
}
unsigned long long sclp_get_rzm(void)
{
return sclp_rzm;
}
unsigned int sclp_get_max_cpu(void)
{
return sclp_max_cpu;
}
int sclp_has_siif(void)
{
return sclp_siif;
}
EXPORT_SYMBOL(sclp_has_siif);
unsigned int sclp_get_ibc(void)
{
return sclp_ibc;
}
EXPORT_SYMBOL(sclp_get_ibc);
unsigned int sclp_get_mtid(u8 cpu_type)
{
return cpu_type ? sclp_mtid : sclp_mtid_cp;
}
unsigned int sclp_get_mtid_max(void)
{
return sclp_mtid_max;
}
unsigned int sclp_get_mtid_prev(void)
{
return sclp_mtid_prev;
}
/*
* This function will be called after sclp_facilities_detect(), which gets
* called from early.c code. The sclp_facilities_detect() function retrieves
* and saves the IPL information.
*/
void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
{
*info = sclp_ipl_info;
}
static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
{
int rc;
do {
rc = sclp_cmd_sync_early(cmd, sccb);
} while (rc == -EBUSY);
if (rc)
return -EIO;
if (((struct sccb_header *) sccb)->response_code != 0x0020)
return -EIO;
return 0;
}
static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
{
memset(sccb, 0, sizeof(*sccb));
sccb->hdr.length = sizeof(*sccb);
sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
sccb->evbuf.hdr.type = EVTYP_SDIAS;
sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
sccb->evbuf.event_id = 4712;
sccb->evbuf.dbs = 1;
}
static int __init sclp_set_event_mask(struct init_sccb *sccb,
unsigned long receive_mask,
unsigned long send_mask)
{
memset(sccb, 0, sizeof(*sccb));
sccb->header.length = sizeof(*sccb);
sccb->mask_length = sizeof(sccb_mask_t);
sccb->receive_mask = receive_mask;
sccb->send_mask = send_mask;
return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
}
static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
{
sccb_init_eq_size(sccb);
if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
return -EIO;
if (sccb->evbuf.blk_cnt == 0)
return 0;
return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
}
static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
{
memset(sccb, 0, PAGE_SIZE);
sccb->length = PAGE_SIZE;
if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
return -EIO;
if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
return 0;
return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
}
unsigned long sclp_get_hsa_size(void)
{
return sclp_hsa_size;
}
static void __init sclp_hsa_size_detect(void *sccb)
{
long size;
/* First try synchronous interface (LPAR) */
if (sclp_set_event_mask(sccb, 0, 0x40000010))
return;
size = sclp_hsa_size_init(sccb);
if (size < 0)
return;
if (size != 0)
goto out;
/* Then try asynchronous interface (z/VM) */
if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
return;
size = sclp_hsa_size_init(sccb);
if (size < 0)
return;
size = sclp_hsa_copy_wait(sccb);
if (size < 0)
return;
out:
sclp_hsa_size = size;
}
static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
{
if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
return 0;
if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
return 0;
return 1;
}
static void __init sclp_console_detect(struct init_sccb *sccb)
{
if (sccb->header.response_code != 0x20)
return;
if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
sclp_con_has_vt220 = 1;
if (sclp_con_check_linemode(sccb))
sclp_con_has_linemode = 1;
}
void __init sclp_early_detect(void)
{
void *sccb = &sccb_early;
sclp_facilities_detect(sccb);
sclp_hsa_size_detect(sccb);
/* Turn off SCLP event notifications. Also save remote masks in the
* sccb. These are sufficient to detect sclp console capabilities.
*/
sclp_set_event_mask(sccb, 0, 0);
sclp_console_detect(sccb);
}