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authorTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
committerTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
commite5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch)
treed8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/9/pc/piix4smbus.c
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/9/pc/piix4smbus.c')
-rwxr-xr-xsys/src/9/pc/piix4smbus.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/sys/src/9/pc/piix4smbus.c b/sys/src/9/pc/piix4smbus.c
new file mode 100755
index 000000000..b05bb8f25
--- /dev/null
+++ b/sys/src/9/pc/piix4smbus.c
@@ -0,0 +1,213 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "io.h"
+
+/*
+ * SMBus support for the PIIX4
+ */
+enum
+{
+ IntelVendID= 0x8086,
+ Piix4PMID= 0x7113, /* PIIX4 power management function */
+
+ /* SMBus configuration registers (function 3) */
+ SMBbase= 0x90, /* 4 byte base address (bit 0 == 1, bit 3:1 == 0) */
+ SMBconfig= 0xd2,
+ SMBintrselect= (7<<1),
+ SMIenable= (0<<1), /* interrupts sent to SMI# */
+ IRQ9enable= (4<<1), /* interrupts sent to IRQ9 */
+ SMBenable= (1<<0), /* 1 enables */
+
+ /* SMBus IO space registers */
+ Hoststatus= 0x0, /* (writing 1 bits reset the interrupt bits) */
+ Failed= (1<<4), /* transaction terminated by KILL */
+ Bus_error= (1<<3), /* transaction collision */
+ Dev_error= (1<<2), /* device error interrupt */
+ Host_complete= (1<<1), /* host command completion interrupt */
+ Host_busy= (1<<0), /* */
+ Slavestatus= 0x1, /* (writing 1 bits reset) */
+ Alert_sts= (1<<5), /* someone asserted SMBALERT# */
+ Shdw2_sts= (1<<4), /* slave accessed shadow 2 port */
+ Shdw1_sts= (1<<3), /* slave accessed shadow 1 port */
+ Slv_sts= (1<<2), /* slave accessed shadow 1 port */
+ Slv_bsy= (1<<0),
+ Hostcontrol= 0x2,
+ Start= (1<<6), /* start execution */
+ Cmd_prot= (7<<2), /* command protocol mask */
+ Quick= (0<<2), /* address only */
+ Byte= (1<<2), /* address + cmd */
+ ByteData= (2<<2), /* address + cmd + data */
+ WordData= (3<<2), /* address + cmd + data + data */
+ Kill= (1<<1), /* abort in progress command */
+ Ienable= (1<<0), /* enable completion interrupts */
+ Hostcommand= 0x3,
+ Hostaddress= 0x4,
+ AddressMask= (0x7f<<1), /* target address */
+ Read= (1<<0), /* 1 == read, 0 == write */
+ Hostdata0= 0x5,
+ Hostdata1= 0x6,
+ Blockdata= 0x7,
+ Slavecontrol= 0x8,
+ Alert_en= (1<<3), /* enable inter on SMBALERT# */
+ Shdw2_en= (1<<2), /* enable inter on external shadow 2 access */
+ Shdw1_en= (1<<1), /* enable inter on external shadow 1 access */
+ Slv_en= (1<<0), /* enable inter on access of host ctlr slave port */
+ Shadowcommand= 0x9,
+ Slaveevent= 0xa,
+ Slavedata= 0xc,
+};
+
+static struct
+{
+ int rw;
+ int cmd;
+ int len;
+ int proto;
+} proto[] =
+{
+ [SMBquick] { 0, 0, 0, Quick },
+ [SMBsend] { 0, 1, 0, Byte },
+ [SMBbytewrite] { 0, 1, 1, ByteData },
+ [SMBwordwrite] { 0, 1, 2, WordData },
+ [SMBrecv] { Read, 0, 1, Byte },
+ [SMBbyteread] { Read, 1, 1, ByteData },
+ [SMBwordread] { Read, 1, 2, WordData },
+};
+
+static void
+transact(SMBus *s, int type, int addr, int cmd, uchar *data)
+{
+ int tries, status;
+ char err[256];
+
+ if(type < 0 || type > nelem(proto))
+ panic("piix4smbus: illegal transaction type %d", type);
+
+ if(waserror()){
+ qunlock(s);
+ nexterror();
+ }
+ qlock(s);
+
+ /* wait a while for the host interface to be available */
+ for(tries = 0; tries < 1000000; tries++){
+ if((inb(s->base+Hoststatus) & Host_busy) == 0)
+ break;
+ sched();
+ }
+ if(tries >= 1000000){
+ /* try aborting current transaction */
+ outb(s->base+Hostcontrol, Kill);
+ for(tries = 0; tries < 1000000; tries++){
+ if((inb(s->base+Hoststatus) & Host_busy) == 0)
+ break;
+ sched();
+ }
+ if(tries >= 1000000){
+ snprint(err, sizeof(err), "SMBus jammed: %2.2ux", inb(s->base+Hoststatus));
+ error(err);
+ }
+ }
+
+ /* set up for transaction */
+ outb(s->base+Hostaddress, (addr<<1)|proto[type].rw);
+ if(proto[type].cmd)
+ outb(s->base+Hostcommand, cmd);
+ if(proto[type].rw != Read){
+ switch(proto[type].len){
+ case 2:
+ outb(s->base+Hostdata1, data[1]);
+ /* fall through */
+ case 1:
+ outb(s->base+Hostdata0, data[0]);
+ break;
+ }
+ }
+
+
+ /* reset the completion/error bits and start transaction */
+ outb(s->base+Hoststatus, Failed|Bus_error|Dev_error|Host_complete);
+ outb(s->base+Hostcontrol, Start|proto[type].proto);
+
+ /* wait for completion */
+ status = 0;
+ for(tries = 0; tries < 1000000; tries++){
+ status = inb(s->base+Hoststatus);
+ if(status & (Failed|Bus_error|Dev_error|Host_complete))
+ break;
+ sched();
+ }
+ if((status & Host_complete) == 0){
+ snprint(err, sizeof(err), "SMBus request failed: %2.2ux", status);
+ error(err);
+ }
+
+ /* get results */
+ if(proto[type].rw == Read){
+ switch(proto[type].len){
+ case 2:
+ data[1] = inb(s->base+Hostdata1);
+ /* fall through */
+ case 1:
+ data[0] = inb(s->base+Hostdata0);
+ break;
+ }
+ }
+ qunlock(s);
+ poperror();
+}
+
+static SMBus smbusproto =
+{
+ .transact = transact,
+};
+
+/*
+ * return 0 if this is a piix4 with an smbus interface
+ */
+SMBus*
+piix4smbus(void)
+{
+ Pcidev *p;
+ static SMBus *s;
+
+ if(s != nil)
+ return s;
+
+ p = pcimatch(nil, IntelVendID, Piix4PMID);
+ if(p == nil)
+ return nil;
+
+ s = smalloc(sizeof(*s));
+ memmove(s, &smbusproto, sizeof(*s));
+ s->arg = p;
+
+ /* disable the smbus */
+ pcicfgw8(p, SMBconfig, IRQ9enable|0);
+
+ /* see if bios gave us a viable port space */
+ s->base = pcicfgr32(p, SMBbase) & ~1;
+print("SMB base from bios is 0x%lux\n", s->base);
+ if(ioalloc(s->base, 0xd, 0, "piix4smbus") < 0){
+ s->base = ioalloc(-1, 0xd, 2, "piix4smbus");
+ if(s->base < 0){
+ free(s);
+ print("piix4smbus: can't allocate io port\n");
+ return nil;
+ }
+print("SMB base ialloc is 0x%lux\n", s->base);
+ pcicfgw32(p, SMBbase, s->base|1);
+ }
+
+ /* disable SMBus interrupts, abort any transaction in progress */
+ outb(s->base+Hostcontrol, Kill);
+ outb(s->base+Slavecontrol, 0);
+
+ /* enable the smbus */
+ pcicfgw8(p, SMBconfig, IRQ9enable|SMBenable);
+
+ return s;
+}