Geode MSR support for OpenBSD

This patch adds conditional support for the Geode MSR device on OpenBSD.

Signed-off-by: Marc Balmer <mbalmer@netbsd.org>
Signed-off-by: Matthieu Herrb <matthieu@openbsd.org>

1 files changed, 46 insertions, 4 deletions

diff --git a/src/geode_msr.c b/src/geode_msr.c
index b7c56d9..8f57939 100644
--- a/src/geode_msr.c
+++ b/src/geode_msr.c
@@ -33,18 +33,36 @@
 #include <fcntl.h>
 #include <sys/types.h>
 #include <errno.h>
+
+#ifdef __OpenBSD__
+#include <sys/ioctl.h>
+#include <machine/amdmsr.h>
+#endif
+
 #include "os.h"
 #include "geode.h"
 
+#ifdef __OpenBSD__
+#define _PATH_MSRDEV	"/dev/amdmsr"
+#define X_PRIVSEP
+#else
+#define _PATH_MSRDEV	"/dev/cpu/0/msr"
+#endif
+
 static int
 _msr_open(void)
 {
     static int msrfd = 0;
 
     if (msrfd == 0) {
-        msrfd = open("/dev/cpu/0/msr", O_RDWR);
+#ifdef X_PRIVSEP
+        msrfd = priv_open_device(_PATH_MSRDEV);
+#else
+        msrfd = open(_PATH_MSRDEV, O_RDWR);
+#endif
         if (msrfd == -1)
-            ErrorF("Unable to open /dev/cpu/0/msr: %d\n", errno);
+            FatalError("Unable to open %s: %s\n", _PATH_MSRDEV,
+                strerror(errno));
     }
 
     return msrfd;
@@ -53,6 +71,19 @@ _msr_open(void)
 int
 GeodeReadMSR(unsigned long addr, unsigned long *lo, unsigned long *hi)
 {
+#ifdef __OpenBSD__
+    struct amdmsr_req req;
+    int fd = _msr_open();
+
+    req.addr = addr;
+
+    if (ioctl(fd, RDMSR, &req) == -1)
+	FatalError("Unable to read MSR at address %0x06x: %s\n", addr,
+	    strerror(errno));
+
+    *hi = req.val >> 32;
+    *lo = req.val & 0xffffffff;
+#else
     unsigned int data[2];
     int fd = _msr_open();
     int ret;
@@ -72,13 +103,24 @@ GeodeReadMSR(unsigned long addr, unsigned long *lo, unsigned long *hi)
 
     *hi = data[1];
     *lo = data[0];
-
+#endif
     return 0;
 }
 
 int
 GeodeWriteMSR(unsigned long addr, unsigned long lo, unsigned long hi)
 {
+#ifdef __OpenBSD__
+    struct amdmsr_req req;
+    int fd = _msr_open();
+
+    req.addr = addr;
+    req.val = (u_int64_t) hi << 32 | (u_int64_t)lo;
+
+    if (ioctl(fd, WRMSR, &req) == -1)
+        FatalError("Unable to write MSR at address 0x%06x: %s\n", addr,
+            strerror(errno));
+#else
     unsigned int data[2];
     int fd = _msr_open();
 
@@ -93,6 +135,6 @@ GeodeWriteMSR(unsigned long addr, unsigned long lo, unsigned long hi)
 
     if (write(fd, (void *) data, 8) != 8)
         return -1;
-
+#endif
     return 0;
 }