[mii] Add generic MII reset function

iPXE provides no support for manually configuring the link speed.
Provide a generic routine which should be able to reset any MII/GMII
PHY and enable autonegotiation.

Prototyped-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/net/mii.c b/src/drivers/net/mii.c
new file mode 100644 (file)
index 0000000..c8e6529
--- /dev/null
+++ b/src/drivers/net/mii.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <ipxe/mii.h>
+
+/** @file
+ *
+ * Media Independent Interface
+ *
+ */
+
+/**
+ * Reset MII interface
+ *
+ * @v mii              MII interface
+ * @ret rc             Return status code
+ */
+int mii_reset ( struct mii_interface *mii ) {
+       unsigned int i;
+       int bmcr;
+       int rc;
+
+       /* Power-up, enable autonegotiation and initiate reset */
+       if ( ( rc = mii_write ( mii, MII_BMCR,
+                               ( BMCR_RESET | BMCR_ANENABLE ) ) ) != 0 ) {
+               DBGC ( mii, "MII %p could not write BMCR: %s\n",
+                      mii, strerror ( rc ) );
+               return rc;
+       }
+
+       /* Wait for reset to complete */
+       for ( i = 0 ; i < MII_RESET_MAX_WAIT_MS ; i++ ) {
+
+               /* Check if reset has completed */
+               bmcr = mii_read ( mii, MII_BMCR );
+               if ( bmcr < 0 ) {
+                       rc = bmcr;
+                       DBGC ( mii, "MII %p could not read BMCR: %s\n",
+                              mii, strerror ( rc ) );
+                       return rc;
+               }
+
+               /* If reset is not complete, delay 1ms and retry */
+               if ( bmcr & BMCR_RESET ) {
+                       mdelay ( 1 );
+                       continue;
+               }
+
+               /* Force autonegotation on again, in case it was
+                * cleared by the reset.
+                */
+               if ( ( rc = mii_write ( mii, MII_BMCR, BMCR_ANENABLE ) ) != 0 ){
+                       DBGC ( mii, "MII %p could not write BMCR: %s\n",
+                              mii, strerror ( rc ) );
+                       return rc;
+               }
+
+               DBGC ( mii, "MII %p reset after %dms\n", mii, i );
+               return 0;
+       }
+
+       DBGC ( mii, "MII %p timed out waiting for reset\n", mii );
+       return -ETIMEDOUT;
+}

diff --git a/src/include/ipxe/errfile.h b/src/include/ipxe/errfile.h
index 77c2f8095371ec2a514d61c42fd5326a83356722..87b5ac72ccde68fe6076c37afcbd83d69ec24dfe 100644 (file)
--- a/src/include/ipxe/errfile.h
+++ b/src/include/ipxe/errfile.h
@@ -141,6 +141,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #define ERRFILE_ath9k               ( ERRFILE_DRIVER | 0x005f0000 )
 #define ERRFILE_ath                 ( ERRFILE_DRIVER | 0x00600000 )
 #define ERRFILE_vmxnet3                     ( ERRFILE_DRIVER | 0x00610000 )
+#define ERRFILE_mii                 ( ERRFILE_DRIVER | 0x00620000 )
 
 #define ERRFILE_scsi                ( ERRFILE_DRIVER | 0x00700000 )
 #define ERRFILE_arbel               ( ERRFILE_DRIVER | 0x00710000 )

diff --git a/src/include/ipxe/mii.h b/src/include/ipxe/mii.h
new file mode 100644 (file)
index 0000000..a33a31d
--- /dev/null
+++ b/src/include/ipxe/mii.h
@@ -0,0 +1,86 @@
+#ifndef _IPXE_MII_H
+#define _IPXE_MII_H
+
+/** @file
+ *
+ * Media Independent Interface
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <mii.h>
+#include <ipxe/netdevice.h>
+
+struct mii_interface;
+
+/** MII interface operations */
+struct mii_operations {
+       /**
+        * Read from MII register
+        *
+        * @v mii               MII interface
+        * @v reg               Register address
+        * @ret data            Data read, or negative error
+        */
+       int ( * read ) ( struct mii_interface *mii, unsigned int reg );
+       /**
+        * Write to MII register
+        *
+        * @v mii               MII interface
+        * @v reg               Register address
+        * @v data              Data to write
+        * @ret rc              Return status code
+        */
+       int ( * write ) ( struct mii_interface *mii, unsigned int reg,
+                         unsigned int data );
+};
+
+/** An MII interface */
+struct mii_interface {
+       /** Interface operations */
+       struct mii_operations *op;
+};
+
+/**
+ * Initialise MII interface
+ *
+ * @v mii              MII interface
+ * @v op               MII interface operations
+ */
+static inline __attribute__ (( always_inline )) void
+mii_init ( struct mii_interface *mii, struct mii_operations *op ) {
+       mii->op = op;
+}
+
+/**
+ * Read from MII register
+ *
+ * @v mii              MII interface
+ * @v reg              Register address
+ * @ret data           Data read, or negative error
+ */
+static inline __attribute__ (( always_inline )) int
+mii_read ( struct mii_interface *mii, unsigned int reg ) {
+       return mii->op->read ( mii, reg );
+}
+
+/**
+ * Write to MII register
+ *
+ * @v mii              MII interface
+ * @v reg              Register address
+ * @v data             Data to write
+ * @ret rc             Return status code
+ */
+static inline __attribute__ (( always_inline )) int
+mii_write ( struct mii_interface *mii, unsigned int reg, unsigned int data ) {
+       return mii->op->write ( mii, reg, data );
+}
+
+/** Maximum time to wait for a reset, in milliseconds */
+#define MII_RESET_MAX_WAIT_MS 500
+
+extern int mii_reset ( struct mii_interface *mii );
+
+#endif /* _IPXE_MII_H */