linux/drivers/s390/char/sclp_early.c
Michael Holzheu e657d8fe2f s390/sclp: Determine HSA size dynamically for zfcpdump
Currently we have hardcoded the HSA size to 32 MiB. With this patch the
HSA size is determined dynamically via SCLP in early.c.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-11-15 14:08:40 +01:00

112 lines
2.4 KiB
C

/*
* SCLP early driver
*
* Copyright IBM Corp. 2013
*/
#define KMSG_COMPONENT "sclp_early"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <asm/sclp.h>
#include <asm/ipl.h>
#include "sclp_sdias.h"
#include "sclp.h"
static __initdata char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE);
static unsigned long sclp_hsa_size;
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(unsigned long receive_mask,
unsigned long send_mask)
{
struct init_sccb *sccb = (void *) &sccb_early;
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(void)
{
struct sdias_sccb *sccb = (void *) &sccb_early;
sccb_init_eq_size(sccb);
if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
return -EIO;
if (sccb->evbuf.blk_cnt != 0)
return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
return 0;
}
static long __init sclp_hsa_copy_wait(void)
{
struct sccb_header *sccb = (void *) &sccb_early;
memset(sccb, 0, PAGE_SIZE);
sccb->length = PAGE_SIZE;
if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
return -EIO;
return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
}
unsigned long sclp_get_hsa_size(void)
{
return sclp_hsa_size;
}
void __init sclp_hsa_size_detect(void)
{
long size;
/* First try synchronous interface (LPAR) */
if (sclp_set_event_mask(0, 0x40000010))
return;
size = sclp_hsa_size_init();
if (size < 0)
return;
if (size != 0)
goto out;
/* Then try asynchronous interface (z/VM) */
if (sclp_set_event_mask(0x00000010, 0x40000010))
return;
size = sclp_hsa_size_init();
if (size < 0)
return;
size = sclp_hsa_copy_wait();
if (size < 0)
return;
out:
sclp_set_event_mask(0, 0);
sclp_hsa_size = size;
}