diff options
Diffstat (limited to 'drivers/net/ethernet/ibm/emac/tah.c')
| -rw-r--r-- | drivers/net/ethernet/ibm/emac/tah.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ibm/emac/tah.c b/drivers/net/ethernet/ibm/emac/tah.c new file mode 100644 index 000000000..008bbdaf1 --- /dev/null +++ b/drivers/net/ethernet/ibm/emac/tah.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * drivers/net/ethernet/ibm/emac/tah.c + * + * Driver for PowerPC 4xx on-chip ethernet controller, TAH support. + * + * Copyright 2007 Benjamin Herrenschmidt, IBM Corp. + * <benh@kernel.crashing.org> + * + * Based on the arch/ppc version of the driver: + * + * Copyright 2004 MontaVista Software, Inc. + * Matt Porter <mporter@kernel.crashing.org> + * + * Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net> + */ +#include <linux/of_address.h> +#include <asm/io.h> + +#include "emac.h" +#include "core.h" + +int tah_attach(struct platform_device *ofdev, int channel) +{ + struct tah_instance *dev = platform_get_drvdata(ofdev); + + mutex_lock(&dev->lock); + /* Reset has been done at probe() time... nothing else to do for now */ + ++dev->users; + mutex_unlock(&dev->lock); + + return 0; +} + +void tah_detach(struct platform_device *ofdev, int channel) +{ + struct tah_instance *dev = platform_get_drvdata(ofdev); + + mutex_lock(&dev->lock); + --dev->users; + mutex_unlock(&dev->lock); +} + +void tah_reset(struct platform_device *ofdev) +{ + struct tah_instance *dev = platform_get_drvdata(ofdev); + struct tah_regs __iomem *p = dev->base; + int n; + + /* Reset TAH */ + out_be32(&p->mr, TAH_MR_SR); + n = 100; + while ((in_be32(&p->mr) & TAH_MR_SR) && n) + --n; + + if (unlikely(!n)) + printk(KERN_ERR "%pOF: reset timeout\n", ofdev->dev.of_node); + + /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */ + out_be32(&p->mr, + TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP | + TAH_MR_DIG); +} + +int tah_get_regs_len(struct platform_device *ofdev) +{ + return sizeof(struct emac_ethtool_regs_subhdr) + + sizeof(struct tah_regs); +} + +void *tah_dump_regs(struct platform_device *ofdev, void *buf) +{ + struct tah_instance *dev = platform_get_drvdata(ofdev); + struct emac_ethtool_regs_subhdr *hdr = buf; + struct tah_regs *regs = (struct tah_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 tah_regs)); + return regs + 1; +} + +static int tah_probe(struct platform_device *ofdev) +{ + struct device_node *np = ofdev->dev.of_node; + struct tah_instance *dev; + struct resource regs; + int rc; + + rc = -ENOMEM; + dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL); + if (dev == NULL) + goto err_gone; + + mutex_init(&dev->lock); + dev->ofdev = ofdev; + + rc = -ENXIO; + if (of_address_to_resource(np, 0, ®s)) { + printk(KERN_ERR "%pOF: Can't get registers address\n", np); + goto err_free; + } + + rc = -ENOMEM; + dev->base = (struct tah_regs __iomem *)ioremap(regs.start, + sizeof(struct tah_regs)); + if (dev->base == NULL) { + printk(KERN_ERR "%pOF: Can't map device registers!\n", np); + goto err_free; + } + + platform_set_drvdata(ofdev, dev); + + /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */ + tah_reset(ofdev); + + printk(KERN_INFO "TAH %pOF initialized\n", ofdev->dev.of_node); + wmb(); + + return 0; + + err_free: + kfree(dev); + err_gone: + return rc; +} + +static int tah_remove(struct platform_device *ofdev) +{ + struct tah_instance *dev = platform_get_drvdata(ofdev); + + WARN_ON(dev->users != 0); + + iounmap(dev->base); + kfree(dev); + + return 0; +} + +static const struct of_device_id tah_match[] = +{ + { + .compatible = "ibm,tah", + }, + /* For backward compat with old DT */ + { + .type = "tah", + }, + {}, +}; + +static struct platform_driver tah_driver = { + .driver = { + .name = "emac-tah", + .of_match_table = tah_match, + }, + .probe = tah_probe, + .remove = tah_remove, +}; + +int __init tah_init(void) +{ + return platform_driver_register(&tah_driver); +} + +void tah_exit(void) +{ + platform_driver_unregister(&tah_driver); +} |