FIS(2) FIS(2)
NAME
setfissig, txmodefis, atapirwfis, featfis, flushcachefis,
identifyfis, nopfis, rwfis, skelfis, sigtofis, fiswr, fisrw,
id16, id32, id64, idmove, idfeat, idwwn, idss, idpuis,
pflag, fistosig, sasbhash, sashash - SATA/SAS FIS and drive
feature functions
SYNOPSIS
#include <u.h>
#include <libc.h>
#include <fis.h>
enum {
Fissize = 0x20, /* nominal (fits all) fis size */
Dlba = 1<<0,
Dllba = 1<<1,
Dsmart = 1<<2,
Dpower = 1<<3,
Dnop = 1<<4,
Datapi = 1<<5,
Datapi16 = 1<<6,
Data8 = 1<<7,
Dsct = 1<<8,
};
enum {
Pspinup = 1<<0,
Pidready = 1<<1,
};
struct Sfis {
ushort feat; /* features supportd */
uchar udma; /* modes supported */
uchar speeds; /* sata: allowed speeds */
uint sectsz; /* sector size */
uint phystol; /* log2(logical/physical) */
uint sig; /* signature */
uint c; /* cylinder */
uint h; /* head */
uint s; /* sector */
};
void setfissig(Sfis *sfis, uint sig)
int txmodefis(Sfis *sfis, uchar *fis, uchar mode)
int featfis(Sfis *sfis, uchar *fis, uchar feat)
int flushcachefis(Sfis *sfis, uchar *fis)
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FIS(2) FIS(2)
int identifyfis(Sfis *sfis, uchar *fis)
int nopfis(Sfis *sfis, uchar *fis, int srst)
int fisrw(Sfis *f, uchar *fis, int *count)
int rwfis(Sfis *sfis, uchar *fis, int rw, int nsect, uvlong lba)
int atapirwfis(Sfis *sfis, uchar *fis, uchar *cdb, int cdblen, int ndata)
void skelfis(uchar *fis)
void sigtofis(Sfis *sfis, uchar *d2hfis)
uvlong fisrw(Sfis *sfis, uchar *fis, int *nsect)
ushort id16(ushort *id, int idx)
uint id32(ushort *id, int idx)
uvlong id64(ushort *id, int idx)
void idmove(char *buf, ushort *ididx, int n)
vlong idfeat(Sfis *sfis, ushort *id)
uvlong idwwn(Sfis*, ushort *id)
int idss(Sfis *sfis, ushort *id)
int idpuis(ushort *id)
char *pflag(char *p, char *e, Sfis *sbis)
uint fistosig(uchar *fis)
uint sashash(uvlong u)
uchar* sasbhash(uchar *t, uchar *s)
DESCRIPTION
The Sfis type describes the connection between an ATA drive
and a Host Bus Adaptor (HBA). The details of this connec-
tion, such as DMA and LBA support, and the logcal sectors
per physical sector are used to construct the proper SATA
FISes.
Since ATA uses a seperate sector size for addressing (the
logical sector size) and for ECC calculations (the physical
sector size), the library returns values based on the physi-
cal sector size. This allows clients to make intelligent
decisions about IO size without worrying about this
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FIS(2) FIS(2)
implementation botch.
feat selected features supported by the drive. Set by
idfeat.
udma the UDMA modes supported by the drive. Set by
idfeat.
speeds bitmaped signaling speeds supported by the device.
SATA drives may support 1.5gbit/s, 3.0gbit/s and
6.0gbit/s signaling.
sig this field contains the drive's “signature.”
Drives that support the packet command set have a
signature of 0xeb140000, while conventional drives
have a signature of 0x0101. The signature is set
by setfissig. See sd(3) for more information.
c, h, s the number of physical or logical cylinders, heads
and sectors claimed by the drive. CHS addressing
is not allowed by SATA drivers. Set by idfeat.
Typically, a client starts by filling out sfis->sig. Device
drivers typically have an ideosyncratic method of obtaining
a signature. Clients of sd(3) can use special commands to
obtain a signature. Given a signature the client can use
identifyfis to identify the device and finally idfeat, idss
and idwwn to fill out the structure and extract the maximum
LBA+1 and the sector size.
The xtofis functions create FISes to be sent from the host
to the device. These are called H2D or Host to Device Reg-
ister FISes. All require a fis buffer of at least Fislen
bytes. The return value is the ATA protocol of the returned
command. For example, identifyfis returns
Pin|Ppio|P28|P512.
setfissig(sfis, sig)
sets the device's ATA signature.
identifyfis(sfis, fis)
builds an ATA IDENTIFY DEVICE or IDENTIFY PACKET DEVICE
FIS, based on sfis->sig.
id16(id, idx), id32, id64
return id word, double-world or quad-word at position
idx.
idss(sfis, id)
return the physical sector size of the disk. The phys-
ical sector size is the quanta protected by ECC and is
never smaller than the logical sector size, which is
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FIS(2) FIS(2)
used in LBA calcuations.
idpuis(id)
checks for PUIS (power up in standby) modes. Invalid
id blocks return -1. Otherwise Pspinup is set if the
drive needs SET FEATURES subcommand 7 to return com-
plete data and Pidready bit set if the id block is com-
plete. Both or neither bits may be set.
idfeat(sfis, id)
parses the 512-byte data block returned by the identify
commands. On success, the last LBA+1 is returned.
Unparseable or unsupportable data blocks return -1.
Flags may be converted to a descriptive string with
pflag. Idss and idwwn return the sector size and World
Wide Name from the same data.
idmove(buf, ididx, n)
converts an ATA string of length n into a null-
terminated string. Trailing spaces are deleted.
fistosig(fis)
converts a D2H FIS into a device signature.
txmodefis(sfis, fis, mode)
builds a SET TRANSFER MODE FIS.
featfis(sfis, fis, feat)
builds a SET FEATURES FIS.
flushcachefis(sfis, fis)
builds a FLUSH CACHE FIS.
nopfis(sfis, fis, srst)
builds a NOP FIS. If srst is set, then out-of-band
signaling is used to request a soft reset. It is not
expected that srst will be useful outside of device
drivers.
rwfis(sfis, fis, rw, nsect, lba)
generates a FIS requesting an nsect i/o at lba. If rw
is non-zero, then a write is requested otherwise a read
is requested. The correct command to issue is deter-
mined by sfis . DMA and 48-bit (LLBA) commands are pre-
ferred. The inverse is fisrw which returns the lba and
nsect given a FIS generated by rwfis.
atapirwfis(sfis, fis, cdb, cdlen, ndata)
generates an ATAPI read or write FIS. The cdb contains
a cdblen-byte SCSI Command Data Block describing an
nbyte-byte i/o operation.
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FIS(2) FIS(2)
skelfis(fis)
builds a skeleton Host-to-Device (H2D) Register FIS.
Fis must be a buffer of at least Fislen bytes.
The fistox functions create FISes to be sent from the device
to the host. These are called D2H or Device to Host Regis-
ter FISes and are used to generate faux responses where
actual communication with a device would be desirable. All
require a fis buffer of at least Fislen bytes.
sigtofis(sfis, d2hfis)
builds a device signature fis from based on a device's
sfis.
sashash(sasaddr)
generates a 4-byte hashed SAS address from an 8 byte
WWN.
sasbhash(sasaddr, wwn)
fills the buffer sasaddr with the hashed SAS addresse
from the 8 byte buffer wwn.
sigtofis(sfis, d2hfis)
SOURCE
/sys/src/libfis
SEE ALSO
atazz(8), sd(3), sdide(3), sdahci(3), sdodin(3), smart(8)
BUGS
Support for CHS-style addressing is somewhat weak. In par-
ticular, rwfis does not do the usual LBA-to-CHS transations.
This is done by drivers that support CHS addressing. Cur-
rently this is only the IDE driver.
The Sfis structure arguably could contain the LBA size, it
is required for the correct construction of FISes.
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