From 67e6c9246edb12967f49ae1cc67a83ec1a4a9478 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Fri, 29 May 2020 00:21:45 +0200 Subject: [PATCH] net: ks8851: Implement Parallel bus operations Implement accessors for KS8851-16MLL/MLLI/MLLU parallel bus variant of the KS8851. This is based off the ks8851_mll.c , which is a driver for exactly the same hardware, however the ks8851.c code is much higher quality. Hence, this patch pulls out the relevant information from the ks8851_mll.c on how to access the bus, but uses the common ks8851.c code. To make this patch reviewable, instead of rewriting ks8851_mll.c, ks8851_mll.c is removed in a separate subsequent patch. Signed-off-by: Marek Vasut Cc: David S. Miller Cc: Lukas Wunner Cc: Petr Stetiar Cc: YueHaibing Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/ethernet/micrel/Kconfig | 2 + drivers/net/ethernet/micrel/Makefile | 1 + drivers/net/ethernet/micrel/ks8851_par.c | 357 +++++++++++++++++++++++ 3 files changed, 360 insertions(+) create mode 100644 drivers/net/ethernet/micrel/ks8851_par.c diff --git a/drivers/net/ethernet/micrel/Kconfig b/drivers/net/ethernet/micrel/Kconfig index b9c4d48e28e42..09f35209d43d2 100644 --- a/drivers/net/ethernet/micrel/Kconfig +++ b/drivers/net/ethernet/micrel/Kconfig @@ -38,6 +38,8 @@ config KS8851_MLL tristate "Micrel KS8851 MLL" depends on HAS_IOMEM select MII + select CRC32 + select EEPROM_93CX6 ---help--- This platform driver is for Micrel KS8851 Address/data bus multiplexed network chip. diff --git a/drivers/net/ethernet/micrel/Makefile b/drivers/net/ethernet/micrel/Makefile index c7a4725c2e958..5cc00d22c708c 100644 --- a/drivers/net/ethernet/micrel/Makefile +++ b/drivers/net/ethernet/micrel/Makefile @@ -7,4 +7,5 @@ obj-$(CONFIG_KS8842) += ks8842.o obj-$(CONFIG_KS8851) += ks8851.o ks8851-objs = ks8851_common.o ks8851_spi.o obj-$(CONFIG_KS8851_MLL) += ks8851_mll.o +ks8851_mll-objs = ks8851_common.o ks8851_par.o obj-$(CONFIG_KSZ884X_PCI) += ksz884x.o diff --git a/drivers/net/ethernet/micrel/ks8851_par.c b/drivers/net/ethernet/micrel/ks8851_par.c new file mode 100644 index 0000000000000..3bab0cb2b1a56 --- /dev/null +++ b/drivers/net/ethernet/micrel/ks8851_par.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* drivers/net/ethernet/micrel/ks8851.c + * + * Copyright 2009 Simtec Electronics + * http://www.simtec.co.uk/ + * Ben Dooks + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#define DEBUG + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "ks8851.h" + +static int msg_enable; + +#define BE3 0x8000 /* Byte Enable 3 */ +#define BE2 0x4000 /* Byte Enable 2 */ +#define BE1 0x2000 /* Byte Enable 1 */ +#define BE0 0x1000 /* Byte Enable 0 */ + +/** + * struct ks8851_net_par - KS8851 Parallel driver private data + * @ks8851: KS8851 driver common private data + * @lock: Lock to ensure that the device is not accessed when busy. + * @hw_addr : start address of data register. + * @hw_addr_cmd : start address of command register. + * @cmd_reg_cache : command register cached. + * + * The @lock ensures that the chip is protected when certain operations are + * in progress. When the read or write packet transfer is in progress, most + * of the chip registers are not accessible until the transfer is finished + * and the DMA has been de-asserted. + */ +struct ks8851_net_par { + struct ks8851_net ks8851; + spinlock_t lock; + void __iomem *hw_addr; + void __iomem *hw_addr_cmd; + u16 cmd_reg_cache; +}; + +#define to_ks8851_par(ks) container_of((ks), struct ks8851_net_par, ks8851) + +/** + * ks8851_lock_par - register access lock + * @ks: The chip state + * @flags: Spinlock flags + * + * Claim chip register access lock + */ +static void ks8851_lock_par(struct ks8851_net *ks, unsigned long *flags) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + + spin_lock_irqsave(&ksp->lock, *flags); +} + +/** + * ks8851_unlock_par - register access unlock + * @ks: The chip state + * @flags: Spinlock flags + * + * Release chip register access lock + */ +static void ks8851_unlock_par(struct ks8851_net *ks, unsigned long *flags) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + + spin_unlock_irqrestore(&ksp->lock, *flags); +} + +/** + * ks_check_endian - Check whether endianness of the bus is correct + * @ks : The chip information + * + * The KS8851-16MLL EESK pin allows selecting the endianness of the 16bit + * bus. To maintain optimum performance, the bus endianness should be set + * such that it matches the endianness of the CPU. + */ +static int ks_check_endian(struct ks8851_net *ks) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + u16 cider; + + /* + * Read CIDER register first, however read it the "wrong" way around. + * If the endian strap on the KS8851-16MLL in incorrect and the chip + * is operating in different endianness than the CPU, then the meaning + * of BE[3:0] byte-enable bits is also swapped such that: + * BE[3,2,1,0] becomes BE[1,0,3,2] + * + * Luckily for us, the byte-enable bits are the top four MSbits of + * the address register and the CIDER register is at offset 0xc0. + * Hence, by reading address 0xc0c0, which is not impacted by endian + * swapping, we assert either BE[3:2] or BE[1:0] while reading the + * CIDER register. + * + * If the bus configuration is correct, reading 0xc0c0 asserts + * BE[3:2] and this read returns 0x0000, because to read register + * with bottom two LSbits of address set to 0, BE[1:0] must be + * asserted. + * + * If the bus configuration is NOT correct, reading 0xc0c0 asserts + * BE[1:0] and this read returns non-zero 0x8872 value. + */ + iowrite16(BE3 | BE2 | KS_CIDER, ksp->hw_addr_cmd); + cider = ioread16(ksp->hw_addr); + if (!cider) + return 0; + + netdev_err(ks->netdev, "incorrect EESK endian strap setting\n"); + + return -EINVAL; +} + +/** + * ks8851_wrreg16_par - write 16bit register value to chip + * @ks: The chip state + * @reg: The register address + * @val: The value to write + * + * Issue a write to put the value @val into the register specified in @reg. + */ +static void ks8851_wrreg16_par(struct ks8851_net *ks, unsigned int reg, + unsigned int val) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + + ksp->cmd_reg_cache = (u16)reg | ((BE1 | BE0) << (reg & 0x02)); + iowrite16(ksp->cmd_reg_cache, ksp->hw_addr_cmd); + iowrite16(val, ksp->hw_addr); +} + +/** + * ks8851_rdreg16_par - read 16 bit register from chip + * @ks: The chip information + * @reg: The register address + * + * Read a 16bit register from the chip, returning the result + */ +static unsigned int ks8851_rdreg16_par(struct ks8851_net *ks, unsigned int reg) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + + ksp->cmd_reg_cache = (u16)reg | ((BE1 | BE0) << (reg & 0x02)); + iowrite16(ksp->cmd_reg_cache, ksp->hw_addr_cmd); + return ioread16(ksp->hw_addr); +} + +/** + * ks8851_rdfifo_par - read data from the receive fifo + * @ks: The device state. + * @buff: The buffer address + * @len: The length of the data to read + * + * Issue an RXQ FIFO read command and read the @len amount of data from + * the FIFO into the buffer specified by @buff. + */ +static void ks8851_rdfifo_par(struct ks8851_net *ks, u8 *buff, unsigned int len) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + + netif_dbg(ks, rx_status, ks->netdev, + "%s: %d@%p\n", __func__, len, buff); + + ioread16_rep(ksp->hw_addr, (u16 *)buff + 1, len / 2); +} + +/** + * ks8851_wrfifo_par - write packet to TX FIFO + * @ks: The device state. + * @txp: The sk_buff to transmit. + * @irq: IRQ on completion of the packet. + * + * Send the @txp to the chip. This means creating the relevant packet header + * specifying the length of the packet and the other information the chip + * needs, such as IRQ on completion. Send the header and the packet data to + * the device. + */ +static void ks8851_wrfifo_par(struct ks8851_net *ks, struct sk_buff *txp, + bool irq) +{ + struct ks8851_net_par *ksp = to_ks8851_par(ks); + unsigned int len = ALIGN(txp->len, 4); + unsigned int fid = 0; + + netif_dbg(ks, tx_queued, ks->netdev, "%s: skb %p, %d@%p, irq %d\n", + __func__, txp, txp->len, txp->data, irq); + + fid = ks->fid++; + fid &= TXFR_TXFID_MASK; + + if (irq) + fid |= TXFR_TXIC; /* irq on completion */ + + iowrite16(fid, ksp->hw_addr); + iowrite16(txp->len, ksp->hw_addr); + + iowrite16_rep(ksp->hw_addr, txp->data, len / 2); +} + +/** + * ks8851_rx_skb_par - receive skbuff + * @ks: The device state. + * @skb: The skbuff + */ +static void ks8851_rx_skb_par(struct ks8851_net *ks, struct sk_buff *skb) +{ + netif_rx(skb); +} + +static unsigned int ks8851_rdreg16_par_txqcr(struct ks8851_net *ks) +{ + return ks8851_rdreg16_par(ks, KS_TXQCR); +} + +/** + * ks8851_start_xmit_par - transmit packet + * @skb: The buffer to transmit + * @dev: The device used to transmit the packet. + * + * Called by the network layer to transmit the @skb. Queue the packet for + * the device and schedule the necessary work to transmit the packet when + * it is free. + * + * We do this to firstly avoid sleeping with the network device locked, + * and secondly so we can round up more than one packet to transmit which + * means we can try and avoid generating too many transmit done interrupts. + */ +static netdev_tx_t ks8851_start_xmit_par(struct sk_buff *skb, + struct net_device *dev) +{ + struct ks8851_net *ks = netdev_priv(dev); + netdev_tx_t ret = NETDEV_TX_OK; + unsigned long flags; + unsigned int txqcr; + u16 txmir; + int err; + + netif_dbg(ks, tx_queued, ks->netdev, + "%s: skb %p, %d@%p\n", __func__, skb, skb->len, skb->data); + + ks8851_lock_par(ks, &flags); + + txmir = ks8851_rdreg16_par(ks, KS_TXMIR) & 0x1fff; + + if (likely(txmir >= skb->len + 12)) { + ks8851_wrreg16_par(ks, KS_RXQCR, ks->rc_rxqcr | RXQCR_SDA); + ks8851_wrfifo_par(ks, skb, false); + ks8851_wrreg16_par(ks, KS_RXQCR, ks->rc_rxqcr); + ks8851_wrreg16_par(ks, KS_TXQCR, TXQCR_METFE); + + err = readx_poll_timeout_atomic(ks8851_rdreg16_par_txqcr, ks, + txqcr, !(txqcr & TXQCR_METFE), + 5, 1000000); + if (err) + ret = NETDEV_TX_BUSY; + + ks8851_done_tx(ks, skb); + } else { + ret = NETDEV_TX_BUSY; + } + + ks8851_unlock_par(ks, &flags); + + return ret; +} + +static int ks8851_probe_par(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct ks8851_net_par *ksp; + struct net_device *netdev; + struct ks8851_net *ks; + int ret; + + netdev = devm_alloc_etherdev(dev, sizeof(struct ks8851_net_par)); + if (!netdev) + return -ENOMEM; + + ks = netdev_priv(netdev); + + ks->lock = ks8851_lock_par; + ks->unlock = ks8851_unlock_par; + ks->rdreg16 = ks8851_rdreg16_par; + ks->wrreg16 = ks8851_wrreg16_par; + ks->rdfifo = ks8851_rdfifo_par; + ks->wrfifo = ks8851_wrfifo_par; + ks->start_xmit = ks8851_start_xmit_par; + ks->rx_skb = ks8851_rx_skb_par; + +#define STD_IRQ (IRQ_LCI | /* Link Change */ \ + IRQ_RXI | /* RX done */ \ + IRQ_RXPSI) /* RX process stop */ + ks->rc_ier = STD_IRQ; + + ksp = to_ks8851_par(ks); + spin_lock_init(&ksp->lock); + + ksp->hw_addr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(ksp->hw_addr)) + return PTR_ERR(ksp->hw_addr); + + ksp->hw_addr_cmd = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(ksp->hw_addr_cmd)) + return PTR_ERR(ksp->hw_addr_cmd); + + ret = ks_check_endian(ks); + if (ret) + return ret; + + netdev->irq = platform_get_irq(pdev, 0); + + return ks8851_probe_common(netdev, dev, msg_enable); +} + +static int ks8851_remove_par(struct platform_device *pdev) +{ + return ks8851_remove_common(&pdev->dev); +} + +static const struct of_device_id ks8851_match_table[] = { + { .compatible = "micrel,ks8851-mll" }, + { } +}; +MODULE_DEVICE_TABLE(of, ks8851_match_table); + +static struct platform_driver ks8851_driver = { + .driver = { + .name = "ks8851", + .of_match_table = ks8851_match_table, + .pm = &ks8851_pm_ops, + }, + .probe = ks8851_probe_par, + .remove = ks8851_remove_par, +}; +module_platform_driver(ks8851_driver); + +MODULE_DESCRIPTION("KS8851 Network driver"); +MODULE_AUTHOR("Ben Dooks "); +MODULE_LICENSE("GPL"); + +module_param_named(message, msg_enable, int, 0); +MODULE_PARM_DESC(message, "Message verbosity level (0=none, 31=all)"); -- 2.39.5