diff options
Diffstat (limited to 'drivers/s390/char/sclp_early_core.c')
| -rw-r--r-- | drivers/s390/char/sclp_early_core.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/s390/char/sclp_early_core.c b/drivers/s390/char/sclp_early_core.c new file mode 100644 index 000000000000..5029cc87e80f --- /dev/null +++ b/drivers/s390/char/sclp_early_core.c @@ -0,0 +1,208 @@ +/* + * 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; + +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, + 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; + if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_MASK, sccb)) + return -EIO; + if (sccb->header.response_code != 0x20) + return -EIO; + return 0; +} + +unsigned int sclp_early_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 int sclp_early_setup(int disable, int *have_linemode, int *have_vt220) +{ + unsigned long receive_mask, send_mask; + struct init_sccb *sccb; + int rc; + + *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->send_mask & 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) +{ + int have_linemode, have_vt220; + + if (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)); +} |