ibm_emac_mal.c
/*
* drivers/net/ibm_emac/ibm_emac_mal.c
*
* Memory Access Layer (MAL) support
*
* Copyright (c) 2004, 2005 Zultys Technologies.
* Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
*
* Based on original work by
* Benjamin Herrenschmidt <benh@kernel.crashing.org>,
* David Gibson <hermes@gibson.dropbear.id.au>,
*
* Armin Kuster <akuster@mvista.com>
* Copyright 2002 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/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <asm/ocp.h>
#include "ibm_emac_core.h"
#include "ibm_emac_mal.h"
#include "ibm_emac_debug.h"
int __init mal_register_commac(struct ibm_ocp_mal *mal,
struct mal_commac *commac)
{
unsigned long flags;
local_irq_save(flags);
MAL_DBG("%d: reg(%08x, %08x)" NL, mal->def->index,
commac->tx_chan_mask, commac->rx_chan_mask);
/* Don't let multiple commacs claim the same channel(s) */
if ((mal->tx_chan_mask & commac->tx_chan_mask) ||
(mal->rx_chan_mask & commac->rx_chan_mask)) {
local_irq_restore(flags);
printk(KERN_WARNING "mal%d: COMMAC channels conflict!\n",
mal->def->index);
return -EBUSY;
}
mal->tx_chan_mask |= commac->tx_chan_mask;
mal->rx_chan_mask |= commac->rx_chan_mask;
list_add(&commac->list, &mal->list);
local_irq_restore(flags);
return 0;
}
void __exit mal_unregister_commac(struct ibm_ocp_mal *mal,
struct mal_commac *commac)
{
unsigned long flags;
local_irq_save(flags);
MAL_DBG("%d: unreg(%08x, %08x)" NL, mal->def->index,
commac->tx_chan_mask, commac->rx_chan_mask);
mal->tx_chan_mask &= ~commac->tx_chan_mask;
mal->rx_chan_mask &= ~commac->rx_chan_mask;
list_del_init(&commac->list);
local_irq_restore(flags);
}
int mal_set_rcbs(struct ibm_ocp_mal *mal, int channel, unsigned long size)
{
struct ocp_func_mal_data *maldata = mal->def->additions;
BUG_ON(channel < 0 || channel >= maldata->num_rx_chans ||
size > MAL_MAX_RX_SIZE);
MAL_DBG("%d: set_rbcs(%d, %lu)" NL, mal->def->index, channel, size);
if (size & 0xf) {
printk(KERN_WARNING
"mal%d: incorrect RX size %lu for the channel %d\n",
mal->def->index, size, channel);
return -EINVAL;
}
set_mal_dcrn(mal, MAL_RCBS(channel), size >> 4);
return 0;
}
int mal_tx_bd_offset(struct ibm_ocp_mal *mal, int channel)
{
struct ocp_func_mal_data *maldata = mal->def->additions;
BUG_ON(channel < 0 || channel >= maldata->num_tx_chans);
return channel * NUM_TX_BUFF;
}
int mal_rx_bd_offset(struct ibm_ocp_mal *mal, int channel)
{
struct ocp_func_mal_data *maldata = mal->def->additions;
BUG_ON(channel < 0 || channel >= maldata->num_rx_chans);
return maldata->num_tx_chans * NUM_TX_BUFF + channel * NUM_RX_BUFF;
}
void mal_enable_tx_channel(struct ibm_ocp_mal *mal, int channel)
{
local_bh_disable();
MAL_DBG("%d: enable_tx(%d)" NL, mal->def->index, channel);
set_mal_dcrn(mal, MAL_TXCASR,
get_mal_dcrn(mal, MAL_TXCASR) | MAL_CHAN_MASK(channel));
local_bh_enable();
}
void mal_disable_tx_channel(struct ibm_ocp_mal *mal, int channel)
{
set_mal_dcrn(mal, MAL_TXCARR, MAL_CHAN_MASK(channel));
MAL_DBG("%d: disable_tx(%d)" NL, mal->def->index, channel);
}
void mal_enable_rx_channel(struct ibm_ocp_mal *mal, int channel)
{
local_bh_disable();
MAL_DBG("%d: enable_rx(%d)" NL, mal->def->index, channel);
set_mal_dcrn(mal, MAL_RXCASR,
get_mal_dcrn(mal, MAL_RXCASR) | MAL_CHAN_MASK(channel));
local_bh_enable();
}
void mal_disable_rx_channel(struct ibm_ocp_mal *mal, int channel)
{
set_mal_dcrn(mal, MAL_RXCARR, MAL_CHAN_MASK(channel));
MAL_DBG("%d: disable_rx(%d)" NL, mal->def->index, channel);
}
void mal_poll_add(struct ibm_ocp_mal *mal, struct mal_commac *commac)
{
local_bh_disable();
MAL_DBG("%d: poll_add(%p)" NL, mal->def->index, commac);
list_add_tail(&commac->poll_list, &mal->poll_list);
local_bh_enable();
}
void mal_poll_del(struct ibm_ocp_mal *mal, struct mal_commac *commac)
{
local_bh_disable();
MAL_DBG("%d: poll_del(%p)" NL, mal->def->index, commac);
list_del(&commac->poll_list);
local_bh_enable();
}
/* synchronized by mal_poll() */
static inline void mal_enable_eob_irq(struct ibm_ocp_mal *mal)
{
MAL_DBG2("%d: enable_irq" NL, mal->def->index);
set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) | MAL_CFG_EOPIE);
}
/* synchronized by __LINK_STATE_RX_SCHED bit in ndev->state */
static inline void mal_disable_eob_irq(struct ibm_ocp_mal *mal)
{
set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) & ~MAL_CFG_EOPIE);
MAL_DBG2("%d: disable_irq" NL, mal->def->index);
}
static irqreturn_t mal_serr(int irq, void *dev_instance, struct pt_regs *regs)
{
struct ibm_ocp_mal *mal = dev_instance;
u32 esr = get_mal_dcrn(mal, MAL_ESR);
/* Clear the error status register */
set_mal_dcrn(mal, MAL_ESR, esr);
MAL_DBG("%d: SERR %08x" NL, mal->def->index, esr);
if (esr & MAL_ESR_EVB) {
if (esr & MAL_ESR_DE) {
/* We ignore Descriptor error,
* TXDE or RXDE interrupt will be generated anyway.
*/
return IRQ_HANDLED;
}
if (esr & MAL_ESR_PEIN) {
/* PLB error, it's probably buggy hardware or
* incorrect physical address in BD (i.e. bug)
*/
if (net_ratelimit())
printk(KERN_ERR
"mal%d: system error, PLB (ESR = 0x%08x)\n",
mal->def->index, esr);
return IRQ_HANDLED;
}
/* OPB error, it's probably buggy hardware or incorrect EBC setup */
if (net_ratelimit())
printk(KERN_ERR
"mal%d: system error, OPB (ESR = 0x%08x)\n",
mal->def->index, esr);
}
return IRQ_HANDLED;
}
static inline void mal_schedule_poll(struct ibm_ocp_mal *mal)
{
if (likely(netif_rx_schedule_prep(&mal->poll_dev))) {
MAL_DBG2("%d: schedule_poll" NL, mal->def->index);
mal_disable_eob_irq(mal);
__netif_rx_schedule(&mal->poll_dev);
} else
MAL_DBG2("%d: already in poll" NL, mal->def->index);
}
static irqreturn_t mal_txeob(int irq, void *dev_instance, struct pt_regs *regs)
{
struct ibm_ocp_mal *mal = dev_instance;
u32 r = get_mal_dcrn(mal, MAL_TXEOBISR);
MAL_DBG2("%d: txeob %08x" NL, mal->def->index, r);
mal_schedule_poll(mal);
set_mal_dcrn(mal, MAL_TXEOBISR, r);
return IRQ_HANDLED;
}
static irqreturn_t mal_rxeob(int irq, void *dev_instance, struct pt_regs *regs)
{
struct ibm_ocp_mal *mal = dev_instance;
u32 r = get_mal_dcrn(mal, MAL_RXEOBISR);
MAL_DBG2("%d: rxeob %08x" NL, mal->def->index, r);
mal_schedule_poll(mal);
set_mal_dcrn(mal, MAL_RXEOBISR, r);
return IRQ_HANDLED;
}
static irqreturn_t mal_txde(int irq, void *dev_instance, struct pt_regs *regs)
{
struct ibm_ocp_mal *mal = dev_instance;
u32 deir = get_mal_dcrn(mal, MAL_TXDEIR);
set_mal_dcrn(mal, MAL_TXDEIR, deir);
MAL_DBG("%d: txde %08x" NL, mal->def->index, deir);
if (net_ratelimit())
printk(KERN_ERR
"mal%d: TX descriptor error (TXDEIR = 0x%08x)\n",
mal->def->index, deir);
return IRQ_HANDLED;
}
static irqreturn_t mal_rxde(int irq, void *dev_instance, struct pt_regs *regs)
{
struct ibm_ocp_mal *mal = dev_instance;
struct list_head *l;
u32 deir = get_mal_dcrn(mal, MAL_RXDEIR);
MAL_DBG("%d: rxde %08x" NL, mal->def->index, deir);
list_for_each(l, &mal->list) {
struct mal_commac *mc = list_entry(l, struct mal_commac, list);
if (deir & mc->rx_chan_mask) {
mc->rx_stopped = 1;
mc->ops->rxde(mc->dev);
}
}
mal_schedule_poll(mal);
set_mal_dcrn(mal, MAL_RXDEIR, deir);
return IRQ_HANDLED;
}
static int mal_poll(struct net_device *ndev, int *budget)
{
struct ibm_ocp_mal *mal = ndev->priv;
struct list_head *l;
int rx_work_limit = min(ndev->quota, *budget), received = 0, done;
MAL_DBG2("%d: poll(%d) %d ->" NL, mal->def->index, *budget,
rx_work_limit);
again:
/* Process TX skbs */
list_for_each(l, &mal->poll_list) {
struct mal_commac *mc =
list_entry(l, struct mal_commac, poll_list);
mc->ops->poll_tx(mc->dev);
}
/* Process RX skbs.
* We _might_ need something more smart here to enforce polling fairness.
*/
list_for_each(l, &mal->poll_list) {
struct mal_commac *mc =
list_entry(l, struct mal_commac, poll_list);
int n = mc->ops->poll_rx(mc->dev, rx_work_limit);
if (n) {
received += n;
rx_work_limit -= n;
if (rx_work_limit <= 0) {
done = 0;
goto more_work; // XXX What if this is the last one ?
}
}
}
/* We need to disable IRQs to protect from RXDE IRQ here */
local_irq_disable();
__netif_rx_complete(ndev);
mal_enable_eob_irq(mal);
local_irq_enable();
done = 1;
/* Check for "rotting" packet(s) */
list_for_each(l, &mal->poll_list) {
struct mal_commac *mc =
list_entry(l, struct mal_commac, poll_list);
if (unlikely(mc->ops->peek_rx(mc->dev) || mc->rx_stopped)) {
MAL_DBG2("%d: rotting packet" NL, mal->def->index);
if (netif_rx_reschedule(ndev, received))
mal_disable_eob_irq(mal);
else
MAL_DBG2("%d: already in poll list" NL,
mal->def->index);
if (rx_work_limit > 0)
goto again;
else
goto more_work;
}
mc->ops->poll_tx(mc->dev);
}
more_work:
ndev->quota -= received;
*budget -= received;
MAL_DBG2("%d: poll() %d <- %d" NL, mal->def->index, *budget,
done ? 0 : 1);
return done ? 0 : 1;
}
static void mal_reset(struct ibm_ocp_mal *mal)
{
int n = 10;
MAL_DBG("%d: reset" NL, mal->def->index);
set_mal_dcrn(mal, MAL_CFG, MAL_CFG_SR);
/* Wait for reset to complete (1 system clock) */
while ((get_mal_dcrn(mal, MAL_CFG) & MAL_CFG_SR) && n)
--n;
if (unlikely(!n))
printk(KERN_ERR "mal%d: reset timeout\n", mal->def->index);
}
int mal_get_regs_len(struct ibm_ocp_mal *mal)
{
return sizeof(struct emac_ethtool_regs_subhdr) +
sizeof(struct ibm_mal_regs);
}
void *mal_dump_regs(struct ibm_ocp_mal *mal, void *buf)
{
struct emac_ethtool_regs_subhdr *hdr = buf;
struct ibm_mal_regs *regs = (struct ibm_mal_regs *)(hdr + 1);
struct ocp_func_mal_data *maldata = mal->def->additions;
int i;
hdr->version = MAL_VERSION;
hdr->index = mal->def->index;
regs->tx_count = maldata->num_tx_chans;
regs->rx_count = maldata->num_rx_chans;
regs->cfg = get_mal_dcrn(mal, MAL_CFG);
regs->esr = get_mal_dcrn(mal, MAL_ESR);
regs->ier = get_mal_dcrn(mal, MAL_IER);
regs->tx_casr = get_mal_dcrn(mal, MAL_TXCASR);
regs->tx_carr = get_mal_dcrn(mal, MAL_TXCARR);
regs->tx_eobisr = get_mal_dcrn(mal, MAL_TXEOBISR);
regs->tx_deir = get_mal_dcrn(mal, MAL_TXDEIR);
regs->rx_casr = get_mal_dcrn(mal, MAL_RXCASR);
regs->rx_carr = get_mal_dcrn(mal, MAL_RXCARR);
regs->rx_eobisr = get_mal_dcrn(mal, MAL_RXEOBISR);
regs->rx_deir = get_mal_dcrn(mal, MAL_RXDEIR);
for (i = 0; i < regs->tx_count; ++i)
regs->tx_ctpr[i] = get_mal_dcrn(mal, MAL_TXCTPR(i));
for (i = 0; i < regs->rx_count; ++i) {
regs->rx_ctpr[i] = get_mal_dcrn(mal, MAL_RXCTPR(i));
regs->rcbs[i] = get_mal_dcrn(mal, MAL_RCBS(i));
}
return regs + 1;
}
static int __init mal_probe(struct ocp_device *ocpdev)
{
struct ibm_ocp_mal *mal;
struct ocp_func_mal_data *maldata;
int err = 0, i, bd_size;
MAL_DBG("%d: probe" NL, ocpdev->def->index);
maldata = ocpdev->def->additions;
if (maldata == NULL) {
printk(KERN_ERR "mal%d: missing additional data!\n",
ocpdev->def->index);
return -ENODEV;
}
mal = kzalloc(sizeof(struct ibm_ocp_mal), GFP_KERNEL);
if (!mal) {
printk(KERN_ERR
"mal%d: out of memory allocating MAL structure!\n",
ocpdev->def->index);
return -ENOMEM;
}
mal->dcrbase = maldata->dcr_base;
mal->def = ocpdev->def;
INIT_LIST_HEAD(&mal->poll_list);
set_bit(__LINK_STATE_START, &mal->poll_dev.state);
mal->poll_dev.weight = CONFIG_IBM_EMAC_POLL_WEIGHT;
mal->poll_dev.poll = mal_poll;
mal->poll_dev.priv = mal;
atomic_set(&mal->poll_dev.refcnt, 1);
INIT_LIST_HEAD(&mal->list);
/* Load power-on reset defaults */
mal_reset(mal);
/* Set the MAL configuration register */
set_mal_dcrn(mal, MAL_CFG, MAL_CFG_DEFAULT | MAL_CFG_PLBB |
MAL_CFG_OPBBL | MAL_CFG_LEA);
mal_enable_eob_irq(mal);
/* Allocate space for BD rings */
BUG_ON(maldata->num_tx_chans <= 0 || maldata->num_tx_chans > 32);
BUG_ON(maldata->num_rx_chans <= 0 || maldata->num_rx_chans > 32);
bd_size = sizeof(struct mal_descriptor) *
(NUM_TX_BUFF * maldata->num_tx_chans +
NUM_RX_BUFF * maldata->num_rx_chans);
mal->bd_virt =
dma_alloc_coherent(&ocpdev->dev, bd_size, &mal->bd_dma, GFP_KERNEL);
if (!mal->bd_virt) {
printk(KERN_ERR
"mal%d: out of memory allocating RX/TX descriptors!\n",
mal->def->index);
err = -ENOMEM;
goto fail;
}
memset(mal->bd_virt, 0, bd_size);
for (i = 0; i < maldata->num_tx_chans; ++i)
set_mal_dcrn(mal, MAL_TXCTPR(i), mal->bd_dma +
sizeof(struct mal_descriptor) *
mal_tx_bd_offset(mal, i));
for (i = 0; i < maldata->num_rx_chans; ++i)
set_mal_dcrn(mal, MAL_RXCTPR(i), mal->bd_dma +
sizeof(struct mal_descriptor) *
mal_rx_bd_offset(mal, i));
err = request_irq(maldata->serr_irq, mal_serr, 0, "MAL SERR", mal);
if (err)
goto fail2;
err = request_irq(maldata->txde_irq, mal_txde, 0, "MAL TX DE", mal);
if (err)
goto fail3;
err = request_irq(maldata->txeob_irq, mal_txeob, 0, "MAL TX EOB", mal);
if (err)
goto fail4;
err = request_irq(maldata->rxde_irq, mal_rxde, 0, "MAL RX DE", mal);
if (err)
goto fail5;
err = request_irq(maldata->rxeob_irq, mal_rxeob, 0, "MAL RX EOB", mal);
if (err)
goto fail6;
/* Enable all MAL SERR interrupt sources */
set_mal_dcrn(mal, MAL_IER, MAL_IER_EVENTS);
/* Advertise this instance to the rest of the world */
ocp_set_drvdata(ocpdev, mal);
mal_dbg_register(mal->def->index, mal);
printk(KERN_INFO "mal%d: initialized, %d TX channels, %d RX channels\n",
mal->def->index, maldata->num_tx_chans, maldata->num_rx_chans);
return 0;
fail6:
free_irq(maldata->rxde_irq, mal);
fail5:
free_irq(maldata->txeob_irq, mal);
fail4:
free_irq(maldata->txde_irq, mal);
fail3:
free_irq(maldata->serr_irq, mal);
fail2:
dma_free_coherent(&ocpdev->dev, bd_size, mal->bd_virt, mal->bd_dma);
fail:
kfree(mal);
return err;
}
static void __exit mal_remove(struct ocp_device *ocpdev)
{
struct ibm_ocp_mal *mal = ocp_get_drvdata(ocpdev);
struct ocp_func_mal_data *maldata = mal->def->additions;
MAL_DBG("%d: remove" NL, mal->def->index);
/* Syncronize with scheduled polling,
stolen from net/core/dev.c:dev_close()
*/
clear_bit(__LINK_STATE_START, &mal->poll_dev.state);
netif_poll_disable(&mal->poll_dev);
if (!list_empty(&mal->list)) {
/* This is *very* bad */
printk(KERN_EMERG
"mal%d: commac list is not empty on remove!\n",
mal->def->index);
}
ocp_set_drvdata(ocpdev, NULL);
free_irq(maldata->serr_irq, mal);
free_irq(maldata->txde_irq, mal);
free_irq(maldata->txeob_irq, mal);
free_irq(maldata->rxde_irq, mal);
free_irq(maldata->rxeob_irq, mal);
mal_reset(mal);
mal_dbg_register(mal->def->index, NULL);
dma_free_coherent(&ocpdev->dev,
sizeof(struct mal_descriptor) *
(NUM_TX_BUFF * maldata->num_tx_chans +
NUM_RX_BUFF * maldata->num_rx_chans), mal->bd_virt,
mal->bd_dma);
kfree(mal);
}
/* Structure for a device driver */
static struct ocp_device_id mal_ids[] = {
{ .vendor = OCP_VENDOR_IBM, .function = OCP_FUNC_MAL },
{ .vendor = OCP_VENDOR_INVALID}
};
static struct ocp_driver mal_driver = {
.name = "mal",
.id_table = mal_ids,
.probe = mal_probe,
.remove = mal_remove,
};
int __init mal_init(void)
{
MAL_DBG(": init" NL);
return ocp_register_driver(&mal_driver);
}
void __exit mal_exit(void)
{
MAL_DBG(": exit" NL);
ocp_unregister_driver(&mal_driver);
}