// SPDX-License-Identifier: GPL-2.0-or-later /* * drivers/net/ethernet/ibm/emac/mal.c * * Memory Access Layer (MAL) support * * Copyright 2007 Benjamin Herrenschmidt, IBM Corp. * <benh@kernel.crashing.org> * * Based on the arch/ppc version of the driver: * * 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. */ #include <linux/delay.h> #include <linux/slab.h> #include <linux/of.h> #include <linux/of_irq.h> #include <linux/platform_device.h> #include "core.h" #include <asm/dcr-regs.h> static int mal_count; int mal_register_commac(struct mal_instance *mal, struct mal_commac *commac) { unsigned long flags; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "reg(%08x, %08x)" NL, 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)) { spin_unlock_irqrestore(&mal->lock, flags); printk(KERN_WARNING "mal%d: COMMAC channels conflict!\n", mal->index); return -EBUSY; } if (list_empty(&mal->list)) napi_enable(&mal->napi); mal->tx_chan_mask |= commac->tx_chan_mask; mal->rx_chan_mask |= commac->rx_chan_mask; list_add(&commac->list, &mal->list); spin_unlock_irqrestore(&mal->lock, flags); return 0; } void mal_unregister_commac(struct mal_instance *mal, struct mal_commac *commac) { unsigned long flags; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "unreg(%08x, %08x)" NL, 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); if (list_empty(&mal->list)) napi_disable(&mal->napi); spin_unlock_irqrestore(&mal->lock, flags); } int mal_set_rcbs(struct mal_instance *mal, int channel, unsigned long size) { BUG_ON(channel < 0 || channel >= mal->num_rx_chans || size > MAL_MAX_RX_SIZE); MAL_DBG(mal, "set_rbcs(%d, %lu)" NL, channel, size); if (size & 0xf) { printk(KERN_WARNING "mal%d: incorrect RX size %lu for the channel %d\n", mal->index, size, channel); return -EINVAL; } set_mal_dcrn(mal, MAL_RCBS(channel), size >> 4); return 0; } int mal_tx_bd_offset(struct mal_instance *mal, int channel) { BUG_ON(channel < 0 || channel >= mal->num_tx_chans); return channel * NUM_TX_BUFF; } int mal_rx_bd_offset(struct mal_instance *mal, int channel) { BUG_ON(channel < 0 || channel >= mal->num_rx_chans); return mal->num_tx_chans * NUM_TX_BUFF + channel * NUM_RX_BUFF; } void mal_enable_tx_channel(struct mal_instance *mal, int channel) { unsigned long flags; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "enable_tx(%d)" NL, channel); set_mal_dcrn(mal, MAL_TXCASR, get_mal_dcrn(mal, MAL_TXCASR) | MAL_CHAN_MASK(channel)); spin_unlock_irqrestore(&mal->lock, flags); } void mal_disable_tx_channel(struct mal_instance *mal, int channel) { set_mal_dcrn(mal, MAL_TXCARR, MAL_CHAN_MASK(channel)); MAL_DBG(mal, "disable_tx(%d)" NL, channel); } void mal_enable_rx_channel(struct mal_instance *mal, int channel) { unsigned long flags; /* * On some 4xx PPC's (e.g. 460EX/GT), the rx channel is a multiple * of 8, but enabling in MAL_RXCASR needs the divided by 8 value * for the bitmask */ if (!(channel % 8)) channel >>= 3; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "enable_rx(%d)" NL, channel); set_mal_dcrn(mal, MAL_RXCASR, get_mal_dcrn(mal, MAL_RXCASR) | MAL_CHAN_MASK(channel)); spin_unlock_irqrestore(&mal->lock, flags); } void mal_disable_rx_channel(struct mal_instance *mal, int channel) { /* * On some 4xx PPC's (e.g. 460EX/GT), the rx channel is a multiple * of 8, but enabling in MAL_RXCASR needs the divided by 8 value * for the bitmask */ if (!(channel % 8)) channel >>= 3; set_mal_dcrn(mal, MAL_RXCARR, MAL_CHAN_MASK(channel)); MAL_DBG(mal, "disable_rx(%d)" NL, channel); } void mal_poll_add(struct mal_instance *mal, struct mal_commac *commac) { unsigned long flags; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "poll_add(%p)" NL, commac); /* starts disabled */ set_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags); list_add_tail(&commac->poll_list, &mal->poll_list); spin_unlock_irqrestore(&mal->lock, flags); } void mal_poll_del(struct mal_instance *mal, struct mal_commac *commac) { unsigned long flags; spin_lock_irqsave(&mal->lock, flags); MAL_DBG(mal, "poll_del(%p)" NL, commac); list_del(&commac->poll_list); spin_unlock_irqrestore(&mal->lock, flags); } /* synchronized by mal_poll() */ static inline void mal_enable_eob_irq(struct mal_instance *mal) { MAL_DBG2(mal, "enable_irq" NL); // XXX might want to cache MAL_CFG as the DCR read can be slooooow set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) | MAL_CFG_EOPIE); } /* synchronized by NAPI state */ static inline void mal_disable_eob_irq(struct mal_instance *mal) { // XXX might want to cache MAL_CFG as the DCR read can be slooooow set_mal_dcrn(mal, MAL_CFG, get_mal_dcrn(mal, MAL_CFG) & ~MAL_CFG_EOPIE); MAL_DBG2(mal, "disable_irq" NL); } static irqreturn_t mal_serr(int irq, void *dev_instance) { struct mal_instance *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(mal, "SERR %08x" NL, 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->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->index, esr); } return IRQ_HANDLED; } static inline void mal_schedule_poll(struct mal_instance *mal) { if (likely(napi_schedule_prep(&mal->napi))) { MAL_DBG2(mal, "schedule_poll" NL); spin_lock(&mal->lock); mal_disable_eob_irq(mal); spin_unlock(&mal->lock); __napi_schedule(&mal->napi); } else MAL_DBG2(mal, "already in poll" NL); } static irqreturn_t mal_txeob(int irq, void *dev_instance) { struct mal_instance *mal = dev_instance; u32 r = get_mal_dcrn(mal, MAL_TXEOBISR); MAL_DBG2(mal, "txeob %08x" NL, r); mal_schedule_poll(mal); set_mal_dcrn(mal, MAL_TXEOBISR, r); #ifdef CONFIG_PPC_DCR_NATIVE if (mal_has_feature(mal, MAL_FTR_CLEAR_ICINTSTAT)) mtdcri(SDR0, DCRN_SDR_ICINTSTAT, (mfdcri(SDR0, DCRN_SDR_ICINTSTAT) | ICINTSTAT_ICTX)); #endif return IRQ_HANDLED; } static irqreturn_t mal_rxeob(int irq, void *dev_instance) { struct mal_instance *mal = dev_instance; u32 r = get_mal_dcrn(mal, MAL_RXEOBISR); MAL_DBG2(mal, "rxeob %08x" NL, r); mal_schedule_poll(mal); set_mal_dcrn(mal, MAL_RXEOBISR, r); #ifdef CONFIG_PPC_DCR_NATIVE if (mal_has_feature(mal, MAL_FTR_CLEAR_ICINTSTAT)) mtdcri(SDR0, DCRN_SDR_ICINTSTAT, (mfdcri(SDR0, DCRN_SDR_ICINTSTAT) | ICINTSTAT_ICRX)); #endif return IRQ_HANDLED; } static irqreturn_t mal_txde(int irq, void *dev_instance) { struct mal_instance *mal = dev_instance; u32 deir = get_mal_dcrn(mal, MAL_TXDEIR); set_mal_dcrn(mal, MAL_TXDEIR, deir); MAL_DBG(mal, "txde %08x" NL, deir); if (net_ratelimit()) printk(KERN_ERR "mal%d: TX descriptor error (TXDEIR = 0x%08x)\n", mal->index, deir); return IRQ_HANDLED; } static irqreturn_t mal_rxde(int irq, void *dev_instance) { struct mal_instance *mal = dev_instance; struct list_head *l; u32 deir = get_mal_dcrn(mal, MAL_RXDEIR); MAL_DBG(mal, "rxde %08x" NL, deir); list_for_each(l, &mal->list) { struct mal_commac *mc = list_entry(l, struct mal_commac, list); if (deir & mc->rx_chan_mask) { set_bit(MAL_COMMAC_RX_STOPPED, &mc->flags); mc->ops->rxde(mc->dev); } } mal_schedule_poll(mal); set_mal_dcrn(mal, MAL_RXDEIR, deir); return IRQ_HANDLED; } static irqreturn_t mal_int(int irq, void *dev_instance) { struct mal_instance *mal = dev_instance; u32 esr = get_mal_dcrn(mal, MAL_ESR); if (esr & MAL_ESR_EVB) { /* descriptor error */ if (esr & MAL_ESR_DE) { if (esr & MAL_ESR_CIDT) return mal_rxde(irq, dev_instance); else return mal_txde(irq, dev_instance); } else { /* SERR */ return mal_serr(irq, dev_instance); } } return IRQ_HANDLED; } void mal_poll_disable(struct mal_instance *mal, struct mal_commac *commac) { /* Spinlock-type semantics: only one caller disable poll at a time */ while (test_and_set_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags)) msleep(1); /* Synchronize with the MAL NAPI poller */ napi_synchronize(&mal->napi); } void mal_poll_enable(struct mal_instance *mal, struct mal_commac *commac) { smp_wmb(); clear_bit(MAL_COMMAC_POLL_DISABLED, &commac->flags); /* Feels better to trigger a poll here to catch up with events that * may have happened on this channel while disabled. It will most * probably be delayed until the next interrupt but that's mostly a * non-issue in the context where this is called. */ napi_schedule(&mal->napi); } static int mal_poll(struct napi_struct *napi, int budget) { struct mal_instance *mal = container_of(napi, struct mal_instance, napi); struct list_head *l; int received = 0; unsigned long flags; MAL_DBG2(mal, "poll(%d)" NL, budget); /* 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; if (unlikely(test_bit(MAL_COMMAC_POLL_DISABLED, &mc->flags))) continue; n = mc->ops->poll_rx(mc->dev, budget - received); if (n) { received += n; if (received >= budget) return budget; } } if (napi_complete_done(napi, received)) { /* We need to disable IRQs to protect from RXDE IRQ here */ spin_lock_irqsave(&mal->lock, flags); mal_enable_eob_irq(mal); spin_unlock_irqrestore(&mal->lock, flags); } /* 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(test_bit(MAL_COMMAC_POLL_DISABLED, &mc->flags))) continue; if (unlikely(mc->ops->peek_rx(mc->dev) || test_bit(MAL_COMMAC_RX_STOPPED, &mc->flags))) { MAL_DBG2(mal, "rotting packet" NL); if (!napi_reschedule(napi)) goto more_work; spin_lock_irqsave(&mal->lock, flags); mal_disable_eob_irq(mal); spin_unlock_irqrestore(&mal->lock, flags); } mc->ops->poll_tx(mc->dev); } more_work: MAL_DBG2(mal, "poll() %d <- %d" NL, budget, received); return received; } static void mal_reset(struct mal_instance *mal) { int n = 10; MAL_DBG(mal, "reset" NL); 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->index); } int mal_get_regs_len(struct mal_instance *mal) { return sizeof(struct emac_ethtool_regs_subhdr) + sizeof(struct mal_regs); } void *mal_dump_regs(struct mal_instance *mal, void *buf) { struct emac_ethtool_regs_subhdr *hdr = buf; struct mal_regs *regs = (struct mal_regs *)(hdr + 1); int i; hdr->version = mal->version; hdr->index = mal->index; regs->tx_count = mal->num_tx_chans; regs->rx_count = mal->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 mal_probe(struct platform_device *ofdev) { struct mal_instance *mal; int err = 0, i, bd_size; int index = mal_count++; unsigned int dcr_base; const u32 *prop; u32 cfg; unsigned long irqflags; irq_handler_t hdlr_serr, hdlr_txde, hdlr_rxde; mal = kzalloc(sizeof(struct mal_instance), GFP_KERNEL); if (!mal) return -ENOMEM; mal->index = index; mal->ofdev = ofdev; mal->version = of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal2") ? 2 : 1; MAL_DBG(mal, "probe" NL); prop = of_get_property(ofdev->dev.of_node, "num-tx-chans", NULL); if (prop == NULL) { printk(KERN_ERR "mal%d: can't find MAL num-tx-chans property!\n", index); err = -ENODEV; goto fail; } mal->num_tx_chans = prop[0]; prop = of_get_property(ofdev->dev.of_node, "num-rx-chans", NULL); if (prop == NULL) { printk(KERN_ERR "mal%d: can't find MAL num-rx-chans property!\n", index); err = -ENODEV; goto fail; } mal->num_rx_chans = prop[0]; dcr_base = dcr_resource_start(ofdev->dev.of_node, 0); if (dcr_base == 0) { printk(KERN_ERR "mal%d: can't find DCR resource!\n", index); err = -ENODEV; goto fail; } mal->dcr_host = dcr_map(ofdev->dev.of_node, dcr_base, 0x100); if (!DCR_MAP_OK(mal->dcr_host)) { printk(KERN_ERR "mal%d: failed to map DCRs !\n", index); err = -ENODEV; goto fail; } if (of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal-405ez")) { #if defined(CONFIG_IBM_EMAC_MAL_CLR_ICINTSTAT) && \ defined(CONFIG_IBM_EMAC_MAL_COMMON_ERR) mal->features |= (MAL_FTR_CLEAR_ICINTSTAT | MAL_FTR_COMMON_ERR_INT); #else printk(KERN_ERR "%pOF: Support for 405EZ not enabled!\n", ofdev->dev.of_node); err = -ENODEV; goto fail; #endif } mal->txeob_irq = irq_of_parse_and_map(ofdev->dev.of_node, 0); mal->rxeob_irq = irq_of_parse_and_map(ofdev->dev.of_node, 1); mal->serr_irq = irq_of_parse_and_map(ofdev->dev.of_node, 2); if (mal_has_feature(mal, MAL_FTR_COMMON_ERR_INT)) { mal->txde_irq = mal->rxde_irq = mal->serr_irq; } else { mal->txde_irq = irq_of_parse_and_map(ofdev->dev.of_node, 3); mal->rxde_irq = irq_of_parse_and_map(ofdev->dev.of_node, 4); } if (!mal->txeob_irq || !mal->rxeob_irq || !mal->serr_irq || !mal->txde_irq || !mal->rxde_irq) { printk(KERN_ERR "mal%d: failed to map interrupts !\n", index); err = -ENODEV; goto fail_unmap; } INIT_LIST_HEAD(&mal->poll_list); INIT_LIST_HEAD(&mal->list); spin_lock_init(&mal->lock); init_dummy_netdev(&mal->dummy_dev); netif_napi_add_weight(&mal->dummy_dev, &mal->napi, mal_poll, CONFIG_IBM_EMAC_POLL_WEIGHT); /* Load power-on reset defaults */ mal_reset(mal); /* Set the MAL configuration register */ cfg = (mal->version == 2) ? MAL2_CFG_DEFAULT : MAL1_CFG_DEFAULT; cfg |= MAL_CFG_PLBB | MAL_CFG_OPBBL | MAL_CFG_LEA; /* Current Axon is not happy with priority being non-0, it can * deadlock, fix it up here */ if (of_device_is_compatible(ofdev->dev.of_node, "ibm,mcmal-axon")) cfg &= ~(MAL2_CFG_RPP_10 | MAL2_CFG_WPP_10); /* Apply configuration */ set_mal_dcrn(mal, MAL_CFG, cfg); /* Allocate space for BD rings */ BUG_ON(mal->num_tx_chans <= 0 || mal->num_tx_chans > 32); BUG_ON(mal->num_rx_chans <= 0 || mal->num_rx_chans > 32); bd_size = sizeof(struct mal_descriptor) * (NUM_TX_BUFF * mal->num_tx_chans + NUM_RX_BUFF * mal->num_rx_chans); mal->bd_virt = dma_alloc_coherent(&ofdev->dev, bd_size, &mal->bd_dma, GFP_KERNEL); if (mal->bd_virt == NULL) { err = -ENOMEM; goto fail_unmap; } for (i = 0; i < mal->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 < mal->num_rx_chans; ++i) set_mal_dcrn(mal, MAL_RXCTPR(i), mal->bd_dma + sizeof(struct mal_descriptor) * mal_rx_bd_offset(mal, i)); if (mal_has_feature(mal, MAL_FTR_COMMON_ERR_INT)) { irqflags = IRQF_SHARED; hdlr_serr = hdlr_txde = hdlr_rxde = mal_int; } else { irqflags = 0; hdlr_serr = mal_serr; hdlr_txde = mal_txde; hdlr_rxde = mal_rxde; } err = request_irq(mal->serr_irq, hdlr_serr, irqflags, "MAL SERR", mal); if (err) goto fail2; err = request_irq(mal->txde_irq, hdlr_txde, irqflags, "MAL TX DE", mal); if (err) goto fail3; err = request_irq(mal->txeob_irq, mal_txeob, 0, "MAL TX EOB", mal); if (err) goto fail4; err = request_irq(mal->rxde_irq, hdlr_rxde, irqflags, "MAL RX DE", mal); if (err) goto fail5; err = request_irq(mal->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); /* Enable EOB interrupt */ mal_enable_eob_irq(mal); printk(KERN_INFO "MAL v%d %pOF, %d TX channels, %d RX channels\n", mal->version, ofdev->dev.of_node, mal->num_tx_chans, mal->num_rx_chans); /* Advertise this instance to the rest of the world */ wmb(); platform_set_drvdata(ofdev, mal); return 0; fail6: free_irq(mal->rxde_irq, mal); fail5: free_irq(mal->txeob_irq, mal); fail4: free_irq(mal->txde_irq, mal); fail3: free_irq(mal->serr_irq, mal); fail2: dma_free_coherent(&ofdev->dev, bd_size, mal->bd_virt, mal->bd_dma); fail_unmap: dcr_unmap(mal->dcr_host, 0x100); fail: kfree(mal); return err; } static int mal_remove(struct platform_device *ofdev) { struct mal_instance *mal = platform_get_drvdata(ofdev); MAL_DBG(mal, "remove" NL); /* Synchronize with scheduled polling */ napi_disable(&mal->napi); if (!list_empty(&mal->list)) /* This is *very* bad */ WARN(1, KERN_EMERG "mal%d: commac list is not empty on remove!\n", mal->index); free_irq(mal->serr_irq, mal); free_irq(mal->txde_irq, mal); free_irq(mal->txeob_irq, mal); free_irq(mal->rxde_irq, mal); free_irq(mal->rxeob_irq, mal); mal_reset(mal); dma_free_coherent(&ofdev->dev, sizeof(struct mal_descriptor) * (NUM_TX_BUFF * mal->num_tx_chans + NUM_RX_BUFF * mal->num_rx_chans), mal->bd_virt, mal->bd_dma); kfree(mal); return 0; } static const struct of_device_id mal_platform_match[] = { { .compatible = "ibm,mcmal", }, { .compatible = "ibm,mcmal2", }, /* Backward compat */ { .type = "mcmal-dma", .compatible = "ibm,mcmal", }, { .type = "mcmal-dma", .compatible = "ibm,mcmal2", }, {}, }; static struct platform_driver mal_of_driver = { .driver = { .name = "mcmal", .of_match_table = mal_platform_match, }, .probe = mal_probe, .remove = mal_remove, }; int __init mal_init(void) { return platform_driver_register(&mal_of_driver); } void mal_exit(void) { platform_driver_unregister(&mal_of_driver); }