blob: 2f61f5579aa54708213f3226c940ef65c462b72b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 2015
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#include <linux/kernel.h>
#include <asm/processor.h>
#include <asm/lowcore.h>
#include <asm/ebcdic.h>
#include <asm/irq.h>
#include "sclp.h"
#include "sclp_rw.h"
char sclp_early_sccb[PAGE_SIZE] __aligned(PAGE_SIZE) __section(.data);
int sclp_init_state __section(.data) = sclp_init_state_uninitialized;
/*
* Used to keep track of the size of the event masks. Qemu until version 2.11
* only supports 4 and needs a workaround.
*/
bool sclp_mask_compat_mode __section(.data);
void sclp_early_wait_irq(void)
{
unsigned long psw_mask, addr;
psw_t psw_ext_save, psw_wait;
union ctlreg0 cr0, cr0_new;
__ctl_store(cr0.val, 0, 0);
cr0_new.val = cr0.val & ~CR0_IRQ_SUBCLASS_MASK;
cr0_new.lap = 0;
cr0_new.sssm = 1;
__ctl_load(cr0_new.val, 0, 0);
psw_ext_save = S390_lowcore.external_new_psw;
psw_mask = __extract_psw();
S390_lowcore.external_new_psw.mask = psw_mask;
psw_wait.mask = psw_mask | PSW_MASK_EXT | PSW_MASK_WAIT;
S390_lowcore.ext_int_code = 0;
do {
asm volatile(
" larl %[addr],0f\n"
" stg %[addr],%[psw_wait_addr]\n"
" stg %[addr],%[psw_ext_addr]\n"
" lpswe %[psw_wait]\n"
"0:\n"
: [addr] "=&d" (addr),
[psw_wait_addr] "=Q" (psw_wait.addr),
[psw_ext_addr] "=Q" (S390_lowcore.external_new_psw.addr)
: [psw_wait] "Q" (psw_wait)
: "cc", "memory");
} while (S390_lowcore.ext_int_code != EXT_IRQ_SERVICE_SIG);
S390_lowcore.external_new_psw = psw_ext_save;
__ctl_load(cr0.val, 0, 0);
}
int sclp_early_cmd(sclp_cmdw_t cmd, void *sccb)
{
unsigned long flags;
int rc;
raw_local_irq_save(flags);
rc = sclp_service_call(cmd, sccb);
if (rc)
goto out;
sclp_early_wait_irq();
out:
raw_local_irq_restore(flags);
return rc;
}
struct write_sccb {
struct sccb_header header;
struct msg_buf msg;
} __packed;
/* Output multi-line text using SCLP Message interface. */
static void sclp_early_print_lm(const char *str, unsigned int len)
{
unsigned char *ptr, *end, ch;
unsigned int count, offset;
struct write_sccb *sccb;
struct msg_buf *msg;
struct mdb *mdb;
struct mto *mto;
struct go *go;
sccb = (struct write_sccb *) &sclp_early_sccb;
end = (unsigned char *) sccb + sizeof(sclp_early_sccb) - 1;
memset(sccb, 0, sizeof(*sccb));
ptr = (unsigned char *) &sccb->msg.mdb.mto;
offset = 0;
do {
for (count = sizeof(*mto); offset < len; count++) {
ch = str[offset++];
if ((ch == 0x0a) || (ptr + count > end))
break;
ptr[count] = _ascebc[ch];
}
mto = (struct mto *) ptr;
memset(mto, 0, sizeof(*mto));
mto->length = count;
mto->type = 4;
mto->line_type_flags = LNTPFLGS_ENDTEXT;
ptr += count;
} while ((offset < len) && (ptr + sizeof(*mto) <= end));
len = ptr - (unsigned char *) sccb;
sccb->header.length = len - offsetof(struct write_sccb, header);
msg = &sccb->msg;
msg->header.type = EVTYP_MSG;
msg->header.length = len - offsetof(struct write_sccb, msg.header);
mdb = &msg->mdb;
mdb->header.type = 1;
mdb->header.tag = 0xD4C4C240;
mdb->header.revision_code = 1;
mdb->header.length = len - offsetof(struct write_sccb, msg.mdb.header);
go = &mdb->go;
go->length = sizeof(*go);
go->type = 1;
sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
}
struct vt220_sccb {
struct sccb_header header;
struct {
struct evbuf_header header;
char data[];
} msg;
} __packed;
/* Output multi-line text using SCLP VT220 interface. */
static void sclp_early_print_vt220(const char *str, unsigned int len)
{
struct vt220_sccb *sccb;
sccb = (struct vt220_sccb *) &sclp_early_sccb;
if (sizeof(*sccb) + len >= sizeof(sclp_early_sccb))
len = sizeof(sclp_early_sccb) - sizeof(*sccb);
memset(sccb, 0, sizeof(*sccb));
memcpy(&sccb->msg.data, str, len);
sccb->header.length = sizeof(*sccb) + len;
sccb->msg.header.length = sizeof(sccb->msg) + len;
sccb->msg.header.type = EVTYP_VT220MSG;
sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
}
int sclp_early_set_event_mask(struct init_sccb *sccb,
sccb_mask_t receive_mask,
sccb_mask_t send_mask)
{
retry:
memset(sccb, 0, sizeof(*sccb));
sccb->header.length = sizeof(*sccb);
if (sclp_mask_compat_mode)
sccb->mask_length = SCLP_MASK_SIZE_COMPAT;
else
sccb->mask_length = sizeof(sccb_mask_t);
sccb_set_recv_mask(sccb, receive_mask);
sccb_set_send_mask(sccb, send_mask);
if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_MASK, sccb))
return -EIO;
if ((sccb->header.response_code == 0x74f0) && !sclp_mask_compat_mode) {
sclp_mask_compat_mode = true;
goto retry;
}
if (sccb->header.response_code != 0x20)
return -EIO;
return 0;
}
unsigned int sclp_early_con_check_linemode(struct init_sccb *sccb)
{
if (!(sccb_get_sclp_send_mask(sccb) & EVTYP_OPCMD_MASK))
return 0;
if (!(sccb_get_sclp_recv_mask(sccb) & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
return 0;
return 1;
}
unsigned int sclp_early_con_check_vt220(struct init_sccb *sccb)
{
if (sccb_get_sclp_send_mask(sccb) & EVTYP_VT220MSG_MASK)
return 1;
return 0;
}
static int sclp_early_setup(int disable, int *have_linemode, int *have_vt220)
{
unsigned long receive_mask, send_mask;
struct init_sccb *sccb;
int rc;
BUILD_BUG_ON(sizeof(struct init_sccb) > PAGE_SIZE);
*have_linemode = *have_vt220 = 0;
sccb = (struct init_sccb *) &sclp_early_sccb;
receive_mask = disable ? 0 : EVTYP_OPCMD_MASK;
send_mask = disable ? 0 : EVTYP_VT220MSG_MASK | EVTYP_MSG_MASK;
rc = sclp_early_set_event_mask(sccb, receive_mask, send_mask);
if (rc)
return rc;
*have_linemode = sclp_early_con_check_linemode(sccb);
*have_vt220 = !!(sccb_get_send_mask(sccb) & EVTYP_VT220MSG_MASK);
return rc;
}
/*
* Output one or more lines of text on the SCLP console (VT220 and /
* or line-mode).
*/
void __sclp_early_printk(const char *str, unsigned int len, unsigned int force)
{
int have_linemode, have_vt220;
if (!force && sclp_init_state != sclp_init_state_uninitialized)
return;
if (sclp_early_setup(0, &have_linemode, &have_vt220) != 0)
return;
if (have_linemode)
sclp_early_print_lm(str, len);
if (have_vt220)
sclp_early_print_vt220(str, len);
sclp_early_setup(1, &have_linemode, &have_vt220);
}
void sclp_early_printk(const char *str)
{
__sclp_early_printk(str, strlen(str), 0);
}
void sclp_early_printk_force(const char *str)
{
__sclp_early_printk(str, strlen(str), 1);
}