Device tree aware EMAC driver
Based on BenH's earlier work, this is a new version of the EMAC driver
for the built-in ethernet found on PowerPC 4xx embedded CPUs. The
same ASIC is also found in the Axon bridge chip. This new version is
designed to work in the arch/powerpc tree, using the device tree to
probe the device, rather than the old and ugly arch/ppc OCP layer.
This driver is designed to sit alongside the old driver (that lies in
drivers/net/ibm_emac and this one in drivers/net/ibm_newemac). The
old driver is left in place to support arch/ppc until arch/ppc itself
reaches its final demise (not too long now, with luck).
This driver still has a number of things that could do with cleaning
up, but I think they can be fixed up after merging. Specifically:
- Should be adjusted to properly use the dma mapping API.
Axon needs this.
- Probe logic needs reworking, in conjuction with the general
probing code for of_platform devices. The dependencies here between
EMAC, MAL, ZMII etc. make this complicated. At present, it usually
works, because we initialize and register the sub-drivers before the
EMAC driver itself, and (being in driver code) runs after the devices
themselves have been instantiated from the device tree.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/ibm_newemac/zmii.c b/drivers/net/ibm_newemac/zmii.c
new file mode 100644
index 0000000..d063129
--- /dev/null
+++ b/drivers/net/ibm_newemac/zmii.c
@@ -0,0 +1,322 @@
+/*
+ * drivers/net/ibm_newemac/zmii.c
+ *
+ * Driver for PowerPC 4xx on-chip ethernet controller, ZMII bridge support.
+ *
+ * Copyright (c) 2004, 2005 Zultys Technologies.
+ * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
+ *
+ * Based on original work by
+ * Armin Kuster <akuster@mvista.com>
+ * Copyright 2001 MontaVista Softare Inc.
+ *
+ * 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.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/ethtool.h>
+#include <asm/io.h>
+
+#include "emac.h"
+#include "core.h"
+
+/* ZMIIx_FER */
+#define ZMII_FER_MDI(idx) (0x80000000 >> ((idx) * 4))
+#define ZMII_FER_MDI_ALL (ZMII_FER_MDI(0) | ZMII_FER_MDI(1) | \
+ ZMII_FER_MDI(2) | ZMII_FER_MDI(3))
+
+#define ZMII_FER_SMII(idx) (0x40000000 >> ((idx) * 4))
+#define ZMII_FER_RMII(idx) (0x20000000 >> ((idx) * 4))
+#define ZMII_FER_MII(idx) (0x10000000 >> ((idx) * 4))
+
+/* ZMIIx_SSR */
+#define ZMII_SSR_SCI(idx) (0x40000000 >> ((idx) * 4))
+#define ZMII_SSR_FSS(idx) (0x20000000 >> ((idx) * 4))
+#define ZMII_SSR_SP(idx) (0x10000000 >> ((idx) * 4))
+
+/* ZMII only supports MII, RMII and SMII
+ * we also support autodetection for backward compatibility
+ */
+static inline int zmii_valid_mode(int mode)
+{
+ return mode == PHY_MODE_MII ||
+ mode == PHY_MODE_RMII ||
+ mode == PHY_MODE_SMII ||
+ mode == PHY_MODE_NA;
+}
+
+static inline const char *zmii_mode_name(int mode)
+{
+ switch (mode) {
+ case PHY_MODE_MII:
+ return "MII";
+ case PHY_MODE_RMII:
+ return "RMII";
+ case PHY_MODE_SMII:
+ return "SMII";
+ default:
+ BUG();
+ }
+}
+
+static inline u32 zmii_mode_mask(int mode, int input)
+{
+ switch (mode) {
+ case PHY_MODE_MII:
+ return ZMII_FER_MII(input);
+ case PHY_MODE_RMII:
+ return ZMII_FER_RMII(input);
+ case PHY_MODE_SMII:
+ return ZMII_FER_SMII(input);
+ default:
+ return 0;
+ }
+}
+
+int __devinit zmii_attach(struct of_device *ofdev, int input, int *mode)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+ struct zmii_regs *p = dev->base;
+
+ ZMII_DBG(dev, "init(%d, %d)" NL, input, *mode);
+
+ if (!zmii_valid_mode(*mode))
+ /* Probably an EMAC connected to RGMII,
+ * but it still may need ZMII for MDIO so
+ * we don't fail here.
+ */
+ return 0;
+
+ mutex_lock(&dev->lock);
+
+ /* Autodetect ZMII mode if not specified.
+ * This is only for backward compatibility with the old driver.
+ * Please, always specify PHY mode in your board port to avoid
+ * any surprises.
+ */
+ if (dev->mode == PHY_MODE_NA) {
+ if (*mode == PHY_MODE_NA) {
+ u32 r = dev->fer_save;
+
+ ZMII_DBG(dev, "autodetecting mode, FER = 0x%08x" NL, r);
+
+ if (r & (ZMII_FER_MII(0) | ZMII_FER_MII(1)))
+ dev->mode = PHY_MODE_MII;
+ else if (r & (ZMII_FER_RMII(0) | ZMII_FER_RMII(1)))
+ dev->mode = PHY_MODE_RMII;
+ else
+ dev->mode = PHY_MODE_SMII;
+ } else
+ dev->mode = *mode;
+
+ printk(KERN_NOTICE "%s: bridge in %s mode\n",
+ ofdev->node->full_name, zmii_mode_name(dev->mode));
+ } else {
+ /* All inputs must use the same mode */
+ if (*mode != PHY_MODE_NA && *mode != dev->mode) {
+ printk(KERN_ERR
+ "%s: invalid mode %d specified for input %d\n",
+ ofdev->node->full_name, *mode, input);
+ mutex_unlock(&dev->lock);
+ return -EINVAL;
+ }
+ }
+
+ /* Report back correct PHY mode,
+ * it may be used during PHY initialization.
+ */
+ *mode = dev->mode;
+
+ /* Enable this input */
+ out_be32(&p->fer, in_be32(&p->fer) | zmii_mode_mask(dev->mode, input));
+ ++dev->users;
+
+ mutex_unlock(&dev->lock);
+
+ return 0;
+}
+
+void zmii_get_mdio(struct of_device *ofdev, int input)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+ u32 fer;
+
+ ZMII_DBG2(dev, "get_mdio(%d)" NL, input);
+
+ mutex_lock(&dev->lock);
+
+ fer = in_be32(&dev->base->fer) & ~ZMII_FER_MDI_ALL;
+ out_be32(&dev->base->fer, fer | ZMII_FER_MDI(input));
+}
+
+void zmii_put_mdio(struct of_device *ofdev, int input)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+
+ ZMII_DBG2(dev, "put_mdio(%d)" NL, input);
+ mutex_unlock(&dev->lock);
+}
+
+
+void zmii_set_speed(struct of_device *ofdev, int input, int speed)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+ u32 ssr;
+
+ mutex_lock(&dev->lock);
+
+ ssr = in_be32(&dev->base->ssr);
+
+ ZMII_DBG(dev, "speed(%d, %d)" NL, input, speed);
+
+ if (speed == SPEED_100)
+ ssr |= ZMII_SSR_SP(input);
+ else
+ ssr &= ~ZMII_SSR_SP(input);
+
+ out_be32(&dev->base->ssr, ssr);
+
+ mutex_unlock(&dev->lock);
+}
+
+void __devexit zmii_detach(struct of_device *ofdev, int input)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+
+ BUG_ON(!dev || dev->users == 0);
+
+ mutex_lock(&dev->lock);
+
+ ZMII_DBG(dev, "detach(%d)" NL, input);
+
+ /* Disable this input */
+ out_be32(&dev->base->fer,
+ in_be32(&dev->base->fer) & ~zmii_mode_mask(dev->mode, input));
+
+ --dev->users;
+
+ mutex_unlock(&dev->lock);
+}
+
+int zmii_get_regs_len(struct of_device *ofdev)
+{
+ return sizeof(struct emac_ethtool_regs_subhdr) +
+ sizeof(struct zmii_regs);
+}
+
+void *zmii_dump_regs(struct of_device *ofdev, void *buf)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+ struct emac_ethtool_regs_subhdr *hdr = buf;
+ struct zmii_regs *regs = (struct zmii_regs *)(hdr + 1);
+
+ hdr->version = 0;
+ hdr->index = 0; /* for now, are there chips with more than one
+ * zmii ? if yes, then we'll add a cell_index
+ * like we do for emac
+ */
+ memcpy_fromio(regs, dev->base, sizeof(struct zmii_regs));
+ return regs + 1;
+}
+
+static int __devinit zmii_probe(struct of_device *ofdev,
+ const struct of_device_id *match)
+{
+ struct device_node *np = ofdev->node;
+ struct zmii_instance *dev;
+ struct resource regs;
+ int rc;
+
+ rc = -ENOMEM;
+ dev = kzalloc(sizeof(struct zmii_instance), GFP_KERNEL);
+ if (dev == NULL) {
+ printk(KERN_ERR "%s: could not allocate ZMII device!\n",
+ np->full_name);
+ goto err_gone;
+ }
+
+ mutex_init(&dev->lock);
+ dev->ofdev = ofdev;
+ dev->mode = PHY_MODE_NA;
+
+ rc = -ENXIO;
+ if (of_address_to_resource(np, 0, ®s)) {
+ printk(KERN_ERR "%s: Can't get registers address\n",
+ np->full_name);
+ goto err_free;
+ }
+
+ rc = -ENOMEM;
+ dev->base = (struct zmii_regs *)ioremap(regs.start,
+ sizeof(struct zmii_regs));
+ if (dev->base == NULL) {
+ printk(KERN_ERR "%s: Can't map device registers!\n",
+ np->full_name);
+ goto err_free;
+ }
+
+ /* We may need FER value for autodetection later */
+ dev->fer_save = in_be32(&dev->base->fer);
+
+ /* Disable all inputs by default */
+ out_be32(&dev->base->fer, 0);
+
+ printk(KERN_INFO
+ "ZMII %s initialized\n", ofdev->node->full_name);
+ wmb();
+ dev_set_drvdata(&ofdev->dev, dev);
+
+ return 0;
+
+ err_free:
+ kfree(dev);
+ err_gone:
+ return rc;
+}
+
+static int __devexit zmii_remove(struct of_device *ofdev)
+{
+ struct zmii_instance *dev = dev_get_drvdata(&ofdev->dev);
+
+ dev_set_drvdata(&ofdev->dev, NULL);
+
+ WARN_ON(dev->users != 0);
+
+ iounmap(dev->base);
+ kfree(dev);
+
+ return 0;
+}
+
+static struct of_device_id zmii_match[] =
+{
+ {
+ .compatible = "ibm,zmii",
+ },
+ /* For backward compat with old DT */
+ {
+ .type = "emac-zmii",
+ },
+ {},
+};
+
+static struct of_platform_driver zmii_driver = {
+ .name = "emac-zmii",
+ .match_table = zmii_match,
+
+ .probe = zmii_probe,
+ .remove = zmii_remove,
+};
+
+int __init zmii_init(void)
+{
+ return of_register_platform_driver(&zmii_driver);
+}
+
+void zmii_exit(void)
+{
+ of_unregister_platform_driver(&zmii_driver);
+}
