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>

1 files changed, 355 insertions, 0 deletions

diff --git a/drivers/net/ibm_newemac/core.h b/drivers/net/ibm_newemac/core.h
new file mode 100644
index 000000000000..4011803117ca
--- /dev/null
+++ b/drivers/net/ibm_newemac/core.h
@@ -0,0 +1,355 @@
+/*
+ * drivers/net/ibm_newemac/core.h
+ *
+ * Driver for PowerPC 4xx on-chip ethernet controller.
+ *
+ * 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>
+ *      Johnnie Peters <jpeters@mvista.com>
+ *      Copyright 2000, 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.
+ *
+ */
+#ifndef __IBM_NEWEMAC_CORE_H
+#define __IBM_NEWEMAC_CORE_H
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/dma-mapping.h>
+#include <linux/spinlock.h>
+
+#include <asm/of_platform.h>
+#include <asm/io.h>
+#include <asm/dcr.h>
+
+#include "emac.h"
+#include "phy.h"
+#include "zmii.h"
+#include "rgmii.h"
+#include "mal.h"
+#include "tah.h"
+#include "debug.h"
+
+#define NUM_TX_BUFF                     CONFIG_IBM_NEW_EMAC_TXB
+#define NUM_RX_BUFF                     CONFIG_IBM_NEW_EMAC_RXB
+
+/* Simple sanity check */
+#if NUM_TX_BUFF > 256 || NUM_RX_BUFF > 256
+#error Invalid number of buffer descriptors (greater than 256)
+#endif
+
+#define EMAC_MIN_MTU                    46
+
+/* Maximum L2 header length (VLAN tagged, no FCS) */
+#define EMAC_MTU_OVERHEAD               (6 * 2 + 2 + 4)
+
+/* RX BD size for the given MTU */
+static inline int emac_rx_size(int mtu)
+{
+        if (mtu > ETH_DATA_LEN)
+                return MAL_MAX_RX_SIZE;
+        else
+                return mal_rx_size(ETH_DATA_LEN + EMAC_MTU_OVERHEAD);
+}
+
+#define EMAC_DMA_ALIGN(x)               ALIGN((x), dma_get_cache_alignment())
+
+#define EMAC_RX_SKB_HEADROOM            \
+        EMAC_DMA_ALIGN(CONFIG_IBM_NEW_EMAC_RX_SKB_HEADROOM)
+
+/* Size of RX skb for the given MTU */
+static inline int emac_rx_skb_size(int mtu)
+{
+        int size = max(mtu + EMAC_MTU_OVERHEAD, emac_rx_size(mtu));
+        return EMAC_DMA_ALIGN(size + 2) + EMAC_RX_SKB_HEADROOM;
+}
+
+/* RX DMA sync size */
+static inline int emac_rx_sync_size(int mtu)
+{
+        return EMAC_DMA_ALIGN(emac_rx_size(mtu) + 2);
+}
+
+/* Driver statistcs is split into two parts to make it more cache friendly:
+ *   - normal statistics (packet count, etc)
+ *   - error statistics
+ *
+ * When statistics is requested by ethtool, these parts are concatenated,
+ * normal one goes first.
+ *
+ * Please, keep these structures in sync with emac_stats_keys.
+ */
+
+/* Normal TX/RX Statistics */
+struct emac_stats {
+        u64 rx_packets;
+        u64 rx_bytes;
+        u64 tx_packets;
+        u64 tx_bytes;
+        u64 rx_packets_csum;
+        u64 tx_packets_csum;
+};
+
+/* Error statistics */
+struct emac_error_stats {
+        u64 tx_undo;
+
+        /* Software RX Errors */
+        u64 rx_dropped_stack;
+        u64 rx_dropped_oom;
+        u64 rx_dropped_error;
+        u64 rx_dropped_resize;
+        u64 rx_dropped_mtu;
+        u64 rx_stopped;
+        /* BD reported RX errors */
+        u64 rx_bd_errors;
+        u64 rx_bd_overrun;
+        u64 rx_bd_bad_packet;
+        u64 rx_bd_runt_packet;
+        u64 rx_bd_short_event;
+        u64 rx_bd_alignment_error;
+        u64 rx_bd_bad_fcs;
+        u64 rx_bd_packet_too_long;
+        u64 rx_bd_out_of_range;
+        u64 rx_bd_in_range;
+        /* EMAC IRQ reported RX errors */
+        u64 rx_parity;
+        u64 rx_fifo_overrun;
+        u64 rx_overrun;
+        u64 rx_bad_packet;
+        u64 rx_runt_packet;
+        u64 rx_short_event;
+        u64 rx_alignment_error;
+        u64 rx_bad_fcs;
+        u64 rx_packet_too_long;
+        u64 rx_out_of_range;
+        u64 rx_in_range;
+
+        /* Software TX Errors */
+        u64 tx_dropped;
+        /* BD reported TX errors */
+        u64 tx_bd_errors;
+        u64 tx_bd_bad_fcs;
+        u64 tx_bd_carrier_loss;
+        u64 tx_bd_excessive_deferral;
+        u64 tx_bd_excessive_collisions;
+        u64 tx_bd_late_collision;
+        u64 tx_bd_multple_collisions;
+        u64 tx_bd_single_collision;
+        u64 tx_bd_underrun;
+        u64 tx_bd_sqe;
+        /* EMAC IRQ reported TX errors */
+        u64 tx_parity;
+        u64 tx_underrun;
+        u64 tx_sqe;
+        u64 tx_errors;
+};
+
+#define EMAC_ETHTOOL_STATS_COUNT        ((sizeof(struct emac_stats) + \
+                                          sizeof(struct emac_error_stats)) \
+                                         / sizeof(u64))
+
+struct emac_instance {
+        struct net_device               *ndev;
+        struct resource                 rsrc_regs;
+        struct emac_regs                __iomem *emacp;
+        struct of_device                *ofdev;
+        struct device_node              **blist; /* bootlist entry */
+
+        /* MAL linkage */
+        u32                             mal_ph;
+        struct of_device                *mal_dev;
+        u32                             mal_rx_chan;
+        u32                             mal_tx_chan;
+        struct mal_instance             *mal;
+        struct mal_commac               commac;
+
+        /* PHY infos */
+        u32                             phy_mode;
+        u32                             phy_map;
+        u32                             phy_address;
+        u32                             phy_feat_exc;
+        struct mii_phy                  phy;
+        struct mutex                    link_lock;
+        struct delayed_work             link_work;
+        int                             link_polling;
+
+        /* Shared MDIO if any */
+        u32                             mdio_ph;
+        struct of_device                *mdio_dev;
+        struct emac_instance            *mdio_instance;
+        struct mutex                    mdio_lock;
+
+        /* ZMII infos if any */
+        u32                             zmii_ph;
+        u32                             zmii_port;
+        struct of_device                *zmii_dev;
+
+        /* RGMII infos if any */
+        u32                             rgmii_ph;
+        u32                             rgmii_port;
+        struct of_device                *rgmii_dev;
+
+        /* TAH infos if any */
+        u32                             tah_ph;
+        u32                             tah_port;
+        struct of_device                *tah_dev;
+
+        /* IRQs */
+        int                             wol_irq;
+        int                             emac_irq;
+
+        /* OPB bus frequency in Mhz */
+        u32                             opb_bus_freq;
+
+        /* Cell index within an ASIC (for clk mgmnt) */
+        u32                             cell_index;
+
+        /* Max supported MTU */
+        u32                             max_mtu;
+
+        /* Feature bits (from probe table) */
+        unsigned int                    features;
+
+        /* Tx and Rx fifo sizes & other infos in bytes */
+        u32                             tx_fifo_size;
+        u32                             tx_fifo_size_gige;
+        u32                             rx_fifo_size;
+        u32                             rx_fifo_size_gige;
+        u32                             fifo_entry_size;
+        u32                             mal_burst_size; /* move to MAL ? */
+
+        /* Descriptor management
+         */
+        struct mal_descriptor           *tx_desc;
+        int                             tx_cnt;
+        int                             tx_slot;
+        int                             ack_slot;
+
+        struct mal_descriptor           *rx_desc;
+        int                             rx_slot;
+        struct sk_buff                  *rx_sg_skb;     /* 1 */
+        int                             rx_skb_size;
+        int                             rx_sync_size;
+
+        struct sk_buff                  *tx_skb[NUM_TX_BUFF];
+        struct sk_buff                  *rx_skb[NUM_RX_BUFF];
+
+        /* Stats
+         */
+        struct emac_error_stats         estats;
+        struct net_device_stats         nstats;
+        struct emac_stats               stats;
+
+        /* Misc
+         */
+        int                             reset_failed;
+        int                             stop_timeout;   /* in us */
+        int                             no_mcast;
+        int                             mcast_pending;
+        struct work_struct              reset_work;
+        spinlock_t                      lock;
+};
+
+/*
+ * Features of various EMAC implementations
+ */
+
+/*
+ * No flow control on 40x according to the original driver
+ */
+#define EMAC_FTR_NO_FLOW_CONTROL_40x    0x00000001
+/*
+ * Cell is an EMAC4
+ */
+#define EMAC_FTR_EMAC4                  0x00000002
+/*
+ * For the 440SPe, AMCC inexplicably changed the polarity of
+ * the "operation complete" bit in the MII control register.
+ */
+#define EMAC_FTR_STACR_OC_INVERT        0x00000004
+/*
+ * Set if we have a TAH.
+ */
+#define EMAC_FTR_HAS_TAH                0x00000008
+/*
+ * Set if we have a ZMII.
+ */
+#define EMAC_FTR_HAS_ZMII               0x00000010
+/*
+ * Set if we have a RGMII.
+ */
+#define EMAC_FTR_HAS_RGMII              0x00000020
+/*
+ * Set if we have axon-type STACR
+ */
+#define EMAC_FTR_HAS_AXON_STACR         0x00000040
+
+
+/* Right now, we don't quite handle the always/possible masks on the
+ * most optimal way as we don't have a way to say something like
+ * always EMAC4. Patches welcome.
+ */
+enum {
+        EMAC_FTRS_ALWAYS        = 0,
+
+        EMAC_FTRS_POSSIBLE      =
+#ifdef CONFIG_IBM_NEW_EMAC_EMAC4
+            EMAC_FTR_EMAC4      | EMAC_FTR_HAS_AXON_STACR       |
+            EMAC_FTR_STACR_OC_INVERT    |
+#endif
+#ifdef CONFIG_IBM_NEW_EMAC_TAH
+            EMAC_FTR_HAS_TAH    |
+#endif
+#ifdef CONFIG_IBM_NEW_EMAC_ZMII
+            EMAC_FTR_HAS_ZMII   |
+#endif
+#ifdef CONFIG_IBM_NEW_EMAC_RGMII
+            EMAC_FTR_HAS_RGMII  |
+#endif
+            0,
+};
+
+static inline int emac_has_feature(struct emac_instance *dev,
+                                   unsigned long feature)
+{
+        return (EMAC_FTRS_ALWAYS & feature) ||
+               (EMAC_FTRS_POSSIBLE & dev->features & feature);
+}
+
+
+/* Ethtool get_regs complex data.
+ * We want to get not just EMAC registers, but also MAL, ZMII, RGMII, TAH
+ * when available.
+ *
+ * Returned BLOB consists of the ibm_emac_ethtool_regs_hdr,
+ * MAL registers, EMAC registers and optional ZMII, RGMII, TAH registers.
+ * Each register component is preceded with emac_ethtool_regs_subhdr.
+ * Order of the optional headers follows their relative bit posititions
+ * in emac_ethtool_regs_hdr.components
+ */
+#define EMAC_ETHTOOL_REGS_ZMII          0x00000001
+#define EMAC_ETHTOOL_REGS_RGMII         0x00000002
+#define EMAC_ETHTOOL_REGS_TAH           0x00000004
+
+struct emac_ethtool_regs_hdr {
+        u32 components;
+};
+
+struct emac_ethtool_regs_subhdr {
+        u32 version;
+        u32 index;
+};
+
+#endif /* __IBM_NEWEMAC_CORE_H */