/*
 * udbg debug output routine via GELIC UDP broadcasts
 *
 * Copyright (C) 2007 Sony Computer Entertainment Inc.
 * Copyright 2006, 2007 Sony Corporation
 * Copyright (C) 2010 Hector Martin <hector@marcansoft.com>
 * Copyright (C) 2011 Andre Heider <a.heider@gmail.com>
 *
 * 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/if_ether.h>
#include <linux/etherdevice.h>
#include <linux/if_vlan.h>
#include <linux/ip.h>
#include <linux/udp.h>

#include <asm/io.h>
#include <asm/udbg.h>
#include <asm/lv1call.h>

#define GELIC_BUS_ID 1
#define GELIC_DEVICE_ID 0
#define GELIC_DEBUG_PORT 18194
#define GELIC_MAX_MESSAGE_SIZE 1000

#define GELIC_LV1_GET_MAC_ADDRESS 1
#define GELIC_LV1_GET_VLAN_ID 4
#define GELIC_LV1_VLAN_TX_ETHERNET_0 2

#define GELIC_DESCR_DMA_STAT_MASK 0xf0000000
#define GELIC_DESCR_DMA_CARDOWNED 0xa0000000

#define GELIC_DESCR_TX_DMA_IKE 0x00080000
#define GELIC_DESCR_TX_DMA_NO_CHKSUM 0x00000000
#define GELIC_DESCR_TX_DMA_FRAME_TAIL 0x00040000

#define GELIC_DESCR_DMA_CMD_NO_CHKSUM (GELIC_DESCR_DMA_CARDOWNED | \
				       GELIC_DESCR_TX_DMA_IKE | \
				       GELIC_DESCR_TX_DMA_NO_CHKSUM)

static u64 bus_addr;

struct gelic_descr {
	/* as defined by the hardware */
	__be32 buf_addr;
	__be32 buf_size;
	__be32 next_descr_addr;
	__be32 dmac_cmd_status;
	__be32 result_size;
	__be32 valid_size;	/* all zeroes for tx */
	__be32 data_status;
	__be32 data_error;	/* all zeroes for tx */
} __attribute__((aligned(32)));

struct debug_block {
	struct gelic_descr descr;
	u8 pkt[1520];
} __packed;

static __iomem struct ethhdr *h_eth;
static __iomem struct vlan_hdr *h_vlan;
static __iomem struct iphdr *h_ip;
static __iomem struct udphdr *h_udp;

static __iomem char *pmsg;
static __iomem char *pmsgc;

static __iomem struct debug_block dbg __attribute__((aligned(32)));

static int header_size;

static void map_dma_mem(int bus_id, int dev_id, void *start, size_t len,
			u64 *real_bus_addr)
{
	s64 result;
	u64 real_addr = ((u64)start) & 0x0fffffffffffffffUL;
	u64 real_end = real_addr + len;
	u64 map_start = real_addr & ~0xfff;
	u64 map_end = (real_end + 0xfff) & ~0xfff;
	u64 bus_addr = 0;

	u64 flags = 0xf800000000000000UL;

	result = lv1_allocate_device_dma_region(bus_id, dev_id,
						map_end - map_start, 12, 0,
						&bus_addr);
	if (result)
		lv1_panic(0);

	result = lv1_map_device_dma_region(bus_id, dev_id, map_start,
					   bus_addr, map_end - map_start,
					   flags);
	if (result)
		lv1_panic(0);

	*real_bus_addr = bus_addr + real_addr - map_start;
}

static int unmap_dma_mem(int bus_id, int dev_id, u64 bus_addr, size_t len)
{
	s64 result;
	u64 real_bus_addr;

	real_bus_addr = bus_addr & ~0xfff;
	len += bus_addr - real_bus_addr;
	len = (len + 0xfff) & ~0xfff;

	result = lv1_unmap_device_dma_region(bus_id, dev_id, real_bus_addr,
					     len);
	if (result)
		return result;

	return lv1_free_device_dma_region(bus_id, dev_id, real_bus_addr);
}

static void gelic_debug_init(void)
{
	s64 result;
	u64 v2;
	u64 mac;
	u64 vlan_id;

	result = lv1_open_device(GELIC_BUS_ID, GELIC_DEVICE_ID, 0);
	if (result)
		lv1_panic(0);

	map_dma_mem(GELIC_BUS_ID, GELIC_DEVICE_ID, &dbg, sizeof(dbg),
		    &bus_addr);

	memset(&dbg, 0, sizeof(dbg));

	dbg.descr.buf_addr = bus_addr + offsetof(struct debug_block, pkt);

	wmb();

	result = lv1_net_control(GELIC_BUS_ID, GELIC_DEVICE_ID,
				 GELIC_LV1_GET_MAC_ADDRESS, 0, 0, 0,
				 &mac, &v2);
	if (result)
		lv1_panic(0);

	mac <<= 16;

	h_eth = (struct ethhdr *)dbg.pkt;

	eth_broadcast_addr(h_eth->h_dest);
	memcpy(&h_eth->h_source, &mac, ETH_ALEN);

	header_size = sizeof(struct ethhdr);

	result = lv1_net_control(GELIC_BUS_ID, GELIC_DEVICE_ID,
				 GELIC_LV1_GET_VLAN_ID,
				 GELIC_LV1_VLAN_TX_ETHERNET_0, 0, 0,
				 &vlan_id, &v2);
	if (!result) {
		h_eth->h_proto= ETH_P_8021Q;

		header_size += sizeof(struct vlan_hdr);
		h_vlan = (struct vlan_hdr *)(h_eth + 1);
		h_vlan->h_vlan_TCI = vlan_id;
		h_vlan->h_vlan_encapsulated_proto = ETH_P_IP;
		h_ip = (struct iphdr *)(h_vlan + 1);
	} else {
		h_eth->h_proto= 0x0800;
		h_ip = (struct iphdr *)(h_eth + 1);
	}

	header_size += sizeof(struct iphdr);
	h_ip->version = 4;
	h_ip->ihl = 5;
	h_ip->ttl = 10;
	h_ip->protocol = 0x11;
	h_ip->saddr = 0x00000000;
	h_ip->daddr = 0xffffffff;

	header_size += sizeof(struct udphdr);
	h_udp = (struct udphdr *)(h_ip + 1);
	h_udp->source = GELIC_DEBUG_PORT;
	h_udp->dest = GELIC_DEBUG_PORT;

	pmsgc = pmsg = (char *)(h_udp + 1);
}

static void gelic_debug_shutdown(void)
{
	if (bus_addr)
		unmap_dma_mem(GELIC_BUS_ID, GELIC_DEVICE_ID,
			      bus_addr, sizeof(dbg));
	lv1_close_device(GELIC_BUS_ID, GELIC_DEVICE_ID);
}

static void gelic_sendbuf(int msgsize)
{
	u16 *p;
	u32 sum;
	int i;

	dbg.descr.buf_size = header_size + msgsize;
	h_ip->tot_len = msgsize + sizeof(struct udphdr) +
			     sizeof(struct iphdr);
	h_udp->len = msgsize + sizeof(struct udphdr);

	h_ip->check = 0;
	sum = 0;
	p = (u16 *)h_ip;
	for (i = 0; i < 5; i++)
		sum += *p++;
	h_ip->check = ~(sum + (sum >> 16));

	dbg.descr.dmac_cmd_status = GELIC_DESCR_DMA_CMD_NO_CHKSUM |
				    GELIC_DESCR_TX_DMA_FRAME_TAIL;
	dbg.descr.result_size = 0;
	dbg.descr.data_status = 0;

	wmb();

	lv1_net_start_tx_dma(GELIC_BUS_ID, GELIC_DEVICE_ID, bus_addr, 0);

	while ((dbg.descr.dmac_cmd_status & GELIC_DESCR_DMA_STAT_MASK) ==
	       GELIC_DESCR_DMA_CARDOWNED)
		cpu_relax();
}

static void ps3gelic_udbg_putc(char ch)
{
	*pmsgc++ = ch;
	if (ch == '\n' || (pmsgc-pmsg) >= GELIC_MAX_MESSAGE_SIZE) {
		gelic_sendbuf(pmsgc-pmsg);
		pmsgc = pmsg;
	}
}

void __init udbg_init_ps3gelic(void)
{
	gelic_debug_init();
	udbg_putc = ps3gelic_udbg_putc;
}

void udbg_shutdown_ps3gelic(void)
{
	udbg_putc = NULL;
	gelic_debug_shutdown();
}
EXPORT_SYMBOL(udbg_shutdown_ps3gelic);