kernel-ark/include/asm-s390/etr.h
Martin Schwidefsky d54853ef8c [S390] ETR support.
This patch adds support for clock synchronization to an external time
reference (ETR). The external time reference sends an oscillator
signal and a synchronization signal every 2^20 microseconds to keep
the TOD clocks of all connected servers in sync. For availability
two ETR units can be connected to a machine. If the clock deviates
for more than the sync-check tolerance all cpus get a machine check
that indicates that the clock is out of sync. For the lovely details
how to get the clock back in sync see the code below.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 21:18:19 +01:00

220 lines
6.5 KiB
C

/*
* include/asm-s390/etr.h
*
* Copyright IBM Corp. 2006
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/
#ifndef __S390_ETR_H
#define __S390_ETR_H
/* ETR attachment control register */
struct etr_eacr {
unsigned int e0 : 1; /* port 0 stepping control */
unsigned int e1 : 1; /* port 1 stepping control */
unsigned int _pad0 : 5; /* must be 00100 */
unsigned int dp : 1; /* data port control */
unsigned int p0 : 1; /* port 0 change recognition control */
unsigned int p1 : 1; /* port 1 change recognition control */
unsigned int _pad1 : 3; /* must be 000 */
unsigned int ea : 1; /* ETR alert control */
unsigned int es : 1; /* ETR sync check control */
unsigned int sl : 1; /* switch to local control */
} __attribute__ ((packed));
/* Port state returned by steai */
enum etr_psc {
etr_psc_operational = 0,
etr_psc_semi_operational = 1,
etr_psc_protocol_error = 4,
etr_psc_no_symbols = 8,
etr_psc_no_signal = 12,
etr_psc_pps_mode = 13
};
/* Logical port state returned by stetr */
enum etr_lpsc {
etr_lpsc_operational_step = 0,
etr_lpsc_operational_alt = 1,
etr_lpsc_semi_operational = 2,
etr_lpsc_protocol_error = 4,
etr_lpsc_no_symbol_sync = 8,
etr_lpsc_no_signal = 12,
etr_lpsc_pps_mode = 13
};
/* ETR status words */
struct etr_esw {
struct etr_eacr eacr; /* attachment control register */
unsigned int y : 1; /* stepping mode */
unsigned int _pad0 : 5; /* must be 00000 */
unsigned int p : 1; /* stepping port number */
unsigned int q : 1; /* data port number */
unsigned int psc0 : 4; /* port 0 state code */
unsigned int psc1 : 4; /* port 1 state code */
} __attribute__ ((packed));
/* Second level data register status word */
struct etr_slsw {
unsigned int vv1 : 1; /* copy of validity bit data frame 1 */
unsigned int vv2 : 1; /* copy of validity bit data frame 2 */
unsigned int vv3 : 1; /* copy of validity bit data frame 3 */
unsigned int vv4 : 1; /* copy of validity bit data frame 4 */
unsigned int _pad0 : 19; /* must by all zeroes */
unsigned int n : 1; /* EAF port number */
unsigned int v1 : 1; /* validity bit ETR data frame 1 */
unsigned int v2 : 1; /* validity bit ETR data frame 2 */
unsigned int v3 : 1; /* validity bit ETR data frame 3 */
unsigned int v4 : 1; /* validity bit ETR data frame 4 */
unsigned int _pad1 : 4; /* must be 0000 */
} __attribute__ ((packed));
/* ETR data frames */
struct etr_edf1 {
unsigned int u : 1; /* untuned bit */
unsigned int _pad0 : 1; /* must be 0 */
unsigned int r : 1; /* service request bit */
unsigned int _pad1 : 4; /* must be 0000 */
unsigned int a : 1; /* time adjustment bit */
unsigned int net_id : 8; /* ETR network id */
unsigned int etr_id : 8; /* id of ETR which sends data frames */
unsigned int etr_pn : 8; /* port number of ETR output port */
} __attribute__ ((packed));
struct etr_edf2 {
unsigned int etv : 32; /* Upper 32 bits of TOD. */
} __attribute__ ((packed));
struct etr_edf3 {
unsigned int rc : 8; /* failure reason code */
unsigned int _pad0 : 3; /* must be 000 */
unsigned int c : 1; /* ETR coupled bit */
unsigned int tc : 4; /* ETR type code */
unsigned int blto : 8; /* biased local time offset */
/* (blto - 128) * 15 = minutes */
unsigned int buo : 8; /* biased utc offset */
/* (buo - 128) = leap seconds */
} __attribute__ ((packed));
struct etr_edf4 {
unsigned int ed : 8; /* ETS device dependent data */
unsigned int _pad0 : 1; /* must be 0 */
unsigned int buc : 5; /* biased ut1 correction */
/* (buc - 16) * 0.1 seconds */
unsigned int em : 6; /* ETS error magnitude */
unsigned int dc : 6; /* ETS drift code */
unsigned int sc : 6; /* ETS steering code */
} __attribute__ ((packed));
/*
* ETR attachment information block, two formats
* format 1 has 4 reserved words with a size of 64 bytes
* format 2 has 16 reserved words with a size of 96 bytes
*/
struct etr_aib {
struct etr_esw esw;
struct etr_slsw slsw;
unsigned long long tsp;
struct etr_edf1 edf1;
struct etr_edf2 edf2;
struct etr_edf3 edf3;
struct etr_edf4 edf4;
unsigned int reserved[16];
} __attribute__ ((packed,aligned(8)));
/* ETR interruption parameter */
struct etr_interruption_parameter {
unsigned int _pad0 : 8;
unsigned int pc0 : 1; /* port 0 state change */
unsigned int pc1 : 1; /* port 1 state change */
unsigned int _pad1 : 3;
unsigned int eai : 1; /* ETR alert indication */
unsigned int _pad2 : 18;
} __attribute__ ((packed));
/* Query TOD offset result */
struct etr_ptff_qto {
unsigned long long physical_clock;
unsigned long long tod_offset;
unsigned long long logical_tod_offset;
unsigned long long tod_epoch_difference;
} __attribute__ ((packed));
/* Inline assembly helper functions */
static inline int etr_setr(struct etr_eacr *ctrl)
{
int rc = -ENOSYS;
asm volatile(
" .insn s,0xb2160000,0(%2)\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (rc) : "m" (*ctrl), "a" (ctrl));
return rc;
}
/* Stores a format 1 aib with 64 bytes */
static inline int etr_stetr(struct etr_aib *aib)
{
int rc = -ENOSYS;
asm volatile(
" .insn s,0xb2170000,0(%2)\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (rc) : "m" (*aib), "a" (aib));
return rc;
}
/* Stores a format 2 aib with 96 bytes for specified port */
static inline int etr_steai(struct etr_aib *aib, unsigned int func)
{
register unsigned int reg0 asm("0") = func;
int rc = -ENOSYS;
asm volatile(
" .insn s,0xb2b30000,0(%2)\n"
"0: la %0,0\n"
"1:\n"
EX_TABLE(0b,1b)
: "+d" (rc) : "m" (*aib), "a" (aib), "d" (reg0));
return rc;
}
/* Function codes for the steai instruction. */
#define ETR_STEAI_STEPPING_PORT 0x10
#define ETR_STEAI_ALTERNATE_PORT 0x11
#define ETR_STEAI_PORT_0 0x12
#define ETR_STEAI_PORT_1 0x13
static inline int etr_ptff(void *ptff_block, unsigned int func)
{
register unsigned int reg0 asm("0") = func;
register unsigned long reg1 asm("1") = (unsigned long) ptff_block;
int rc = -ENOSYS;
asm volatile(
" .word 0x0104\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (rc), "=m" (ptff_block)
: "d" (reg0), "d" (reg1), "m" (ptff_block) : "cc");
return rc;
}
/* Function codes for the ptff instruction. */
#define ETR_PTFF_QAF 0x00 /* query available functions */
#define ETR_PTFF_QTO 0x01 /* query tod offset */
#define ETR_PTFF_QSI 0x02 /* query steering information */
#define ETR_PTFF_ATO 0x40 /* adjust tod offset */
#define ETR_PTFF_STO 0x41 /* set tod offset */
#define ETR_PTFF_SFS 0x42 /* set fine steering rate */
#define ETR_PTFF_SGS 0x43 /* set gross steering rate */
/* Functions needed by the machine check handler */
extern void etr_switch_to_local(void);
extern void etr_sync_check(void);
#endif /* __S390_ETR_H */