path: root/drivers/s390/char/sclp_cmd.c

/*
 * Copyright IBM Corp. 2007,2012
 *
 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
 *	      Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
 */

#define KMSG_COMPONENT "sclp_cmd"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/completion.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/memory.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <asm/ctl_reg.h>
#include <asm/chpid.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/sclp.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	_reserved0[24 - 11];	/* 11-15 */
	u8	loadparm[8];		/* 24-31 */
	u8	_reserved1[48 - 32];	/* 32-47 */
	u64	facilities;		/* 48-55 */
	u8	_reserved2[84 - 56];	/* 56-83 */
	u8	fac84;			/* 84 */
	u8	fac85;			/* 85 */
	u8	_reserved3[91 - 86];	/* 86-90 */
	u8	flags;			/* 91 */
	u8	_reserved4[100 - 92];	/* 92-99 */
	u32	rnsize2;		/* 100-103 */
	u64	rnmax2;			/* 104-111 */
	u8	_reserved5[4096 - 112];	/* 112-4095 */
} __attribute__((packed, aligned(PAGE_SIZE)));

static struct init_sccb __initdata early_event_mask_sccb __aligned(PAGE_SIZE);
static struct read_info_sccb __initdata early_read_info_sccb;
static int __initdata early_read_info_sccb_valid;

u64 sclp_facilities;
static u8 sclp_fac84;
static u8 sclp_fac85;
static unsigned long long rzm;
static unsigned long long 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 void __init sclp_read_info_early(void)
{
	int rc;
	int i;
	struct read_info_sccb *sccb;
	sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
				  SCLP_CMDW_READ_SCP_INFO};

	sccb = &early_read_info_sccb;
	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) {
			early_read_info_sccb_valid = 1;
			break;
		}
		if (sccb->header.response_code != 0x1f0)
			break;
	}
}

static void __init sclp_event_mask_early(void)
{
	struct init_sccb *sccb = &early_event_mask_sccb;
	int rc;

	do {
		memset(sccb, 0, sizeof(*sccb));
		sccb->header.length = sizeof(*sccb);
		sccb->mask_length = sizeof(sccb_mask_t);
		rc = sclp_cmd_sync_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
	} while (rc == -EBUSY);
}

void __init sclp_facilities_detect(void)
{
	struct read_info_sccb *sccb;

	sclp_read_info_early();
	if (!early_read_info_sccb_valid)
		return;

	sccb = &early_read_info_sccb;
	sclp_facilities = sccb->facilities;
	sclp_fac84 = sccb->fac84;
	sclp_fac85 = sccb->fac85;
	rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
	rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
	rzm <<= 20;

	sclp_event_mask_early();
}

bool __init sclp_has_linemode(void)
{
	struct init_sccb *sccb = &early_event_mask_sccb;

	if (sccb->header.response_code != 0x20)
		return 0;
	if (sccb->sclp_send_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK))
		return 1;
	return 0;
}

bool __init sclp_has_vt220(void)
{
	struct init_sccb *sccb = &early_event_mask_sccb;

	if (sccb->header.response_code != 0x20)
		return 0;
	if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
		return 1;
	return 0;
}

unsigned long long sclp_get_rnmax(void)
{
	return rnmax;
}

unsigned long long sclp_get_rzm(void)
{
	return rzm;
}

u8 sclp_get_fac85(void)
{
	return