/*
 *    Copyright (C) 2005-2006 Michael Ellerman, IBM Corporation
 *    Copyright (C) 2000-2004, IBM Corporation
 *
 *    Description:
 *      This file contains all the routines to build a flattened device
 *      tree for a legacy iSeries machine.
 *
 *      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.
 */

#undef DEBUG

#include <linux/types.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
#include <linux/pci_ids.h>
#include <linux/threads.h>
#include <linux/bitops.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/if_ether.h>	/* ETH_ALEN */

#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/lppaca.h>
#include <asm/cputable.h>
#include <asm/abs_addr.h>
#include <asm/system.h>
#include <asm/iseries/hv_types.h>
#include <asm/iseries/hv_lp_config.h>
#include <asm/iseries/hv_call_xm.h>
#include <asm/udbg.h>

#include "processor_vpd.h"
#include "call_hpt.h"
#include "call_pci.h"
#include "pci.h"
#include "it_exp_vpd_panel.h"
#include "naca.h"

#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif

/*
 * These are created by the linker script at the start and end
 * of the section containing all the strings marked with the DS macro.
 */
extern char __dt_strings_start[];
extern char __dt_strings_end[];

#define DS(s)	({	\
	static const char __s[] __attribute__((section(".dt_strings"))) = s; \
	__s;		\
})

struct iseries_flat_dt {
	struct boot_param_header header;
	u64 reserve_map[2];
};

static void * __initdata dt_data;

/*
 * Putting these strings here keeps them out of the .dt_strings section
 * that we capture for the strings blob of the flattened device tree.
 */
static char __initdata device_type_cpu[] = "cpu";
static char __initdata device_type_memory[] = "memory";
static char __initdata device_type_serial[] = "serial";
static char __initdata device_type_network[] = "network";
static char __initdata device_type_pci[] = "pci";
static char __initdata device_type_vdevice[] = "vdevice";
static char __initdata device_type_vscsi[] = "vscsi";


/* EBCDIC to ASCII conversion routines */

static unsigned char __init e2a(unsigned char x)
{
	switch (x) {
	case 0x81 ... 0x89:
		return x - 0x81 + 'a';
	case 0x91 ... 0x99:
		return x - 0x91 + 'j';
	case 0xA2 ... 0xA9:
		return x - 0xA2 + 's';
	case 0xC1 ... 0xC9:
		return x - 0xC1 + 'A';
	case 0xD1 ... 0xD9:
		return x - 0xD1 + 'J';
	case 0xE2 ... 0xE9:
		return x - 0xE2 + 'S';
	case 0xF0 ... 0xF9:
		return x - 0xF0 + '0';
	}
	return ' ';
}

static unsigned char * __init strne2a(unsigned char *dest,
		const unsigned char *src, size_t n)
{
	int i;

	n = strnlen(src, n);

	for (i = 0; i < n; i++)
		dest[i] = e2a(src[i]);

	return dest;
}

static struct iseries_flat_dt * __init dt_init(void)
{
	struct iseries_flat_dt *dt;
	unsigned long str_len;

	str_len = __dt_strings_end - __dt_strings_start;
	dt = (struct iseries_flat_dt *)ALIGN(klimit, 8);
	dt->header.off_mem_rsvmap =
		offsetof(struct iseries_flat_dt, reserve_map);
	dt->header.off_dt_strings = ALIGN(sizeof(*dt), 8);
	dt->header.off_dt_struct = dt->header.off_dt_strings
		+ ALIGN(str_len, 8);
	dt_data = (void *)((unsigned long)dt + dt->header.off_dt_struct);
	dt->header.dt_strings_size = str_len;

	/* There is no notion of hardware cpu id on iSeries */
	dt->header.boot_cpuid_phys = smp_processor_id();

	memcpy((char *)dt + dt->header.off_dt_strings, __dt_strings_start,
			str_len);

	dt->header.magic = OF_DT_HEADER;
	dt->header.version = 0x10;
	dt->header.last_comp_version = 0x10;

	dt->reserve_map[0] = 0;
	dt->reserve_map[1] = 0;

	return dt;
}

static void __init dt_push_u32(struct iseries_flat_dt *dt, u32 value)
{
	*((u32 *)dt_data) = value;
	dt_data += sizeof(u32);
}

#ifdef notyet
static void __init dt_push_u64(struct iseries_flat_dt *dt, u64 value)
{
	*((u64 *)dt_data) = value;
	dt_data += sizeof(u64);
}
#endif

static void __init dt_push_bytes(struct iseries_flat_dt *dt, const char *data,
		int len)
{
	memcpy(dt_data, data, len);
	dt_data += ALIGN(len, 4);
}

static void __init dt_start_node(struct iseries_flat_dt *dt, const char *name)
{
	dt_push_u32(dt, OF_DT_BEGIN_NODE);
	dt_push_bytes(dt, name, strlen(name) + 1);
}

#define dt_end_node(dt) dt_push_u32(dt, OF_DT_END_NODE)

static void __init __dt_prop(struct iseries_flat_dt *dt, const char *name,
		const void *data, int len)
{
	unsigned long offset;

	dt_push_u32(dt, OF_DT_PROP);

	/* Length of the data */
	dt_push_u32(dt, len);

	offset = name - __dt_strings_start;

	/* The offset of the properties name in the string blob. */
	dt_push_u32(dt, (u32)offset);

	/* The actual data. */
	dt_push_bytes(dt, data, len);
}
#define dt_prop(dt, name, data, len)	__dt_prop((dt), DS(name), (data), (len))

#define dt_prop_str(dt, name, data)	\
	dt_prop((dt), name, (data), strlen((data)) + 1); /* + 1 for NULL */

static void __init __dt_prop_u32(struct iseries_flat_dt *dt, const char *name,
		u32 data)
{
	__dt_prop(dt, name, &data, sizeof(u32));
}
#define dt_prop_u32(dt, name, data)	__dt_prop_u32((dt), DS(name), (data))

static void __init __maybe_unused __dt_prop_u64(struct iseries_flat_dt *dt,
		const char *name, u64 data)
{
	__dt_prop(dt, name, &data, sizeof(u64));
}
#define dt_prop_u64(dt, name, data)	__dt_prop_u64((dt), DS(name), (data))

#define dt_prop_u64_list(dt, name, data, n)	\
	dt_prop((dt), name, (data), sizeof(u64) * (n))

#define dt_prop_u32_list(dt, name, data, n)	\
	dt_prop((dt), name, (data), sizeof(u32) * (n))

#define dt_prop_empty(dt, name)		dt_prop((dt), name, NULL, 0)

static void __init dt_cpus(struct iseries_flat_dt *dt)
{
	unsigned char buf[32];
	unsigned char *p;
	unsigned int i, index;
	struct IoHriProcessorVpd *d;
	u32 pft_size[2];

	/* yuck */
	snprintf(buf, 32, "PowerPC,%s", cur_cpu_spec->cpu_name);
	p = strchr(buf, ' ');
	if (!p) p = buf + strlen(buf);

	dt_start_node(dt, "cpus");
	dt_prop_u32(dt, "#address-cells", 1);
	dt_prop_u32(dt, "#size-cells", 0);

	pft_size[0] = 0; /* NUMA CEC cookie, 0 for non NUMA  */
	pft_size[1] = __ilog2(HvCallHpt_getHptPages() * HW_PAGE_SIZE);

	for (i = 0; i < NR_CPUS; i++) {
		if (lppaca_of(i).dyn_proc_status >= 2)
			continue;

		snprintf(p, 32 - (p - buf), "@%d", i);
		dt_start_node(dt, buf);

		dt_prop_str(dt, "device_type", device_type_cpu);

		index = lppaca_of(i).dyn_hv_phys_proc_index;
		d = &xIoHriProcessorVpd[index];

		dt_prop_u32(dt, "i-cache-size", d->xInstCacheSize * 1024);
		dt_prop_u32(dt, "i-cache-line-size", d->xInstCacheOperandSize);

		dt_prop_u32(dt, "d-cache-size", d->xDataL1CacheSizeKB * 1024);
		dt_prop_u32(dt, "d-cache-line-size", d->xDataCacheOperandSize);

		/* magic conversions to Hz copied from old code */
		dt_prop_u32(dt, "clock-frequency",
			((1UL << 34) * 1000000) / d->xProcFreq);
		dt_prop_u32(dt, "timebase-frequency",
			((1UL << 32) * 1000000) / d->xTimeBaseFreq);

		dt_prop_u32(dt, "reg", i);

		dt_prop_u32_list(dt, "ibm,pft-size", pft_size, 2);

		dt_end_node(dt);
	}

	dt_end_node(dt);
}

static void __init dt_model(struct iseries_flat_dt *dt)
{
	char buf[16] = "IBM,";

	/* N.B. lparcfg.c knows about the "IBM," prefixes ... */
	/* "IBM," + mfgId[2:3] + systemSerial[1:5] */
	strne2a(buf + 4, xItExtVpdPanel.mfgID + 2, 2);
	strne2a(buf + 6, xItExtVpdPanel.systemSerial + 1, 5);
	buf[11] = '\0';
	dt_prop_str(dt, "system-id", buf);

	/* "IBM," + machineType[0:4] */
	strne2a(buf + 4, xItExtVpdPanel.machineType, 4);
	buf[8] = '\0';
	dt_prop_str(dt, "model", buf);

	dt_prop_str(dt, "compatible", "IBM,iSeries");
	dt_prop_u32(dt, "ibm,partition-no", HvLpConfig_getLpIndex());
}

static void __init dt_initrd(struct iseries_flat_dt *dt)
{
#ifdef CONFIG_BLK_DEV_INITRD
	if (naca.xRamDisk) {
		dt_prop_u64(dt, "linux,initrd-start", (u64)naca.xRamDisk);
		dt_prop_u64(dt, "linux,initrd-end",
			(u64)naca.xRamDisk + naca.xRamDiskSize * HW_PAGE_SIZE);
	}
#endif
}

static void __init dt_do_vdevice(struct iseries_flat_dt *dt,
		const char *name, u32 reg, int unit,
		const char *type, const char *compat, int end)
{
	char buf[32];

	snprintf(buf, 32, "%s@%08x", name, reg + ((unit >= 0) ? unit : 0));
	dt_start_node(dt, buf);
	dt_prop_str(dt, "device_type", type);
	if (compat)
		dt_prop_str(dt, "compatible", compat);
	dt_prop_u32(dt, "reg", reg + ((unit >= 0) ? unit : 0));
	if (unit >= 0)
		dt_prop_u32(dt, "linux,unit_address", unit);
	if (end)
		dt_end_node(dt);
}

static void __init dt_vdevices(struct iseries_flat_dt *dt)
{
	u32 reg = 0;
	HvLpIndexMap vlan_map;
	int i;

	dt_start_node(dt, "vdevice");
	dt_prop_str(dt, "device_type", device_type_vdevice);
	dt_prop_str(dt, "compatible", "IBM,iSeries-vdevice");
	dt_prop_u32(dt, "#address-cells", 1);
	dt_prop_u32(dt, "#size-cells", 0);

	dt_do_vdevice(dt, "vty", reg, -1, device_type_serial,
			"IBM,iSeries-vty", 1);
	reg++;

	dt_do_vdevice(dt, "v-scsi", reg, -1, device_type_vscsi,
			"IBM,v-scsi", 1);
	reg++;

	vlan_map = HvLpConfig_getVirtualLanIndexMap();
	for (i = 0; i < HVMAXARCHITECTEDVIRTUALLANS; i++) {
		unsigned char mac_addr[ETH_ALEN];

		if ((vlan_map & (0x8000 >> i)) == 0)
			continue;
		dt_do_vdevice(dt, "l-lan", reg, i, device_type_network,
				"IBM,iSeries-l-lan", 0);
		mac_addr[0] = 0x02;
		mac_addr[1] = 0x01;
		mac_addr[2] = 0xff;
		mac_addr[3] = i;
		mac_addr[4] = 0xff;
		mac_addr[5] = HvLpConfig_getLpIndex_outline();
		dt_prop(dt, "local-mac-address", (char *)mac_addr, ETH_ALEN);
		dt_prop(dt, "mac-address", (char *)mac_addr, ETH_ALEN);
		dt_prop_u32(dt, "max-frame-size", 9000);
		dt_prop_u32(dt, "address-bits", 48);

		dt_end_node(dt);
	}

	dt_end_node(dt);
}

struct pci_class_name {
	u16 code;
	const char *name;
	const char *type;
};

static struct pci_class_name __initdata pci_class_name[] = {
	{ PCI_CLASS_NETWORK_ETHERNET, "ethernet", device_type_network },
};

static struct pci_class_name * __init dt_find_pci_class_name(u16 class_code)
{
	struct pci_class_name *cp;

	for (cp = pci_class_name;
			cp < &pci_class_name[ARRAY_SIZE(pci_class_name)]; cp++)
		if (cp->code == class_code)
			return cp;
	return NULL;
}

/*
 * This assumes that the node slot is always on the primary bus!
 */
static void __init scan_bridge_slot(struct iseries_flat_dt *dt,
		HvBusNumber bus, struct HvCallPci_BridgeInfo *bridge_info)
{
	HvSubBusNumber sub_bus = bridge_info->subBusNumber;
	u16 vendor_id;
	u16 device_id;
	u32 class_id;
	int err;
	char buf[32];
	u32 reg[5];
	int id_sel = ISERIES_GET_DEVICE_FROM_SUBBUS(sub_bus);
	int function = ISERIES_GET_FUNCTION_FROM_SUBBUS(sub_bus);
	HvAgentId eads_id_sel = ISERIES_PCI_AGENTID(id_sel, function);
	u8 devfn;
	struct pci_class_name *cp;

	/*
	 * Connect all functions of any device found.
	 */
	for (id_sel = 1; id_sel <= bridge_info->maxAgents; id_sel++) {
		for (function = 0; function < 8; function++) {
			HvAgentId agent_id = ISERIES_PCI_AGENTID(id_sel,
					function);
			err = HvCallXm_connectBusUnit(bus, sub_bus,
					agent_id, 0);
			if (err) {
				if (err != 0x302)
					DBG("connectBusUnit(%x, %x, %x) %x\n",
						bus, sub_bus, agent_id, err);
				continue;
			}

			err = HvCallPci_configLoad16(bus, sub_bus, agent_id,
					PCI_VENDOR_ID, &vendor_id);
			if (err) {
				DBG("ReadVendor(%x, %x, %x) %x\n",
					bus, sub_bus, agent_id, err);
				continue;
			}
			err = HvCallPci_configLoad16(bus, sub_bus, agent_id,
					PCI_DEVICE_ID, &device_id);
			if (err) {
				DBG("ReadDevice(%x, %x, %x) %x\n",
					bus, sub_bus, agent_id, err);
				continue;
			}
			err = HvCallPci_configLoad32(bus, sub_bus, agent_id,
					PCI_CLASS_REVISION , &class_id);
			if (err) {
				DBG("ReadClass(%x, %x, %x) %x\n",
					bus, sub_bus, agent_id, err);
				continue;
			}

			devfn = PCI_DEVFN(ISERIES_ENCODE_DEVICE(eads_id_sel),
					function);
			cp = dt_find_pci_class_name(class_id >> 16);
			if (cp && cp->name)
				strncpy(buf, cp->name, sizeof(buf) - 1);
			else
				snprintf(buf, sizeof(buf), "pci%x,%x",
						vendor_id, device_id);
			buf[sizeof(buf) - 1] = '\0';
			snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
					"@%x", PCI_SLOT(devfn));
			buf[sizeof(buf) - 1] = '\0';
			if (function != 0)
				snprintf(buf + strlen(buf),
					sizeof(buf) - strlen(buf),
					",%x", function);
			dt_start_node(dt, buf);
			reg[0] = (bus << 16) | (devfn << 8);
			reg[1] = 0;
			reg[2] = 0;
			reg[3] = 0;
			reg[4] = 0;
			dt_prop_u32_list(dt, "reg", reg, 5);
			if (cp && (cp->type || cp->name))
				dt_prop_str(dt, "device_type",
					cp->type ? cp->type : cp->name);
			dt_prop_u32(dt, "vendor-id", vendor_id);
			dt_prop_u32(dt, "device-id", device_id);
			dt_prop_u32(dt, "class-code", class_id >> 8);
			dt_prop_u32(dt, "revision-id", class_id & 0xff);
			dt_prop_u32(dt, "linux,subbus", sub_bus);
			dt_prop_u32(dt, "linux,agent-id", agent_id);
			dt_prop_u32(dt, "linux,logical-slot-number",
					bridge_info->logicalSlotNumber);
			dt_end_node(dt);

		}
	}
}

static void __init scan_bridge(struct iseries_flat_dt *dt, HvBusNumber bus,
		HvSubBusNumber sub_bus, int id_sel)
{
	struct HvCallPci_BridgeInfo bridge_info;
	HvAgentId agent_id;
	int function;
	int ret;

	/* Note: hvSubBus and irq is always be 0 at this level! */
	for (function = 0; function < 8; ++function) {
		agent_id = ISERIES_PCI_AGENTID(id_sel, function);
		ret = HvCallXm_connectBusUnit(bus, sub_bus, agent_id, 0);
		if (ret != 0) {
			if (ret != 0xb)
				DBG("connectBusUnit(%x, %x, %x) %x\n",
						bus, sub_bus, agent_id, ret);
			continue;
		}
		DBG("found device at bus %d idsel %d func %d (AgentId %x)\n",
				bus, id_sel, function, agent_id);
		ret = HvCallPci_getBusUnitInfo(bus, sub_bus, agent_id,
				iseries_hv_addr(&bridge_info),
				sizeof(struct HvCallPci_BridgeInfo));
		if (ret != 0)
			continue;
		DBG("bridge info: type %x subbus %x "
			"maxAgents %x maxsubbus %x logslot %x\n",
			bridge_info.busUnitInfo.deviceType,
			bridge_info.subBusNumber,
			bridge_info.maxAgents,
			bridge_info.maxSubBusNumber,
			bridge_info.logicalSlotNumber);
		if (bridge_info.busUnitInfo.deviceType ==
				HvCallPci_BridgeDevice)
			scan_bridge_slot(dt, bus, &bridge_info);
		else
			DBG("PCI: Invalid Bridge Configuration(0x%02X)",
				bridge_info.busUnitInfo.deviceType);
	}
}

static void __init scan_phb(struct iseries_flat_dt *dt, HvBusNumber bus)
{
	struct HvCallPci_DeviceInfo dev_info;
	const HvSubBusNumber sub_bus = 0;	/* EADs is always 0. */
	int err;
	int id_sel;
	const int max_agents = 8;

	/*
	 * Probe for EADs Bridges
	 */
	for (id_sel = 1; id_sel < max_agents; ++id_sel) {
		err = HvCallPci_getDeviceInfo(bus, sub_bus, id_sel,
				iseries_hv_addr(&dev_info),
				sizeof(struct HvCallPci_DeviceInfo));
		if (err) {
			if (err != 0x302)
				DBG("getDeviceInfo(%x, %x, %x) %x\n",
						bus, sub_bus, id_sel, err);
			continue;
		}
		if (dev_info.deviceType != HvCallPci_NodeDevice) {
			DBG("PCI: Invalid System Configuration"
					"(0x%02X) for bus 0x%02x id 0x%02x.\n",
					dev_info.deviceType, bus, id_sel);
			continue;
		}
		scan_bridge(dt, bus, sub_bus, id_sel);
	}
}

static void __init dt_pci_devices(struct iseries_flat_dt *dt)
{
	HvBusNumber bus;
	char buf[32];
	u32 buses[2];
	int phb_num = 0;

	/* Check all possible buses. */
	for (bus = 0; bus < 256; bus++) {
		int err = HvCallXm_testBus(bus);

		if (err) {
			/*
			 * Check for Unexpected Return code, a clue that
			 * something has gone wrong.
			 */
			if (err != 0x0301)
				DBG("Unexpected Return on Probe(0x%02X) "
						"0x%04X\n", bus, err);
			continue;
		}
		DBG("bus %d appears to exist\n", bus);
		snprintf(buf, 32, "pci@%d", phb_num);
		dt_start_node(dt, buf);
		dt_prop_str(dt, "device_type", device_type_pci);
		dt_prop_str(dt, "compatible", "IBM,iSeries-Logical-PHB");
		dt_prop_u32(dt, "#address-cells", 3);
		dt_prop_u32(dt, "#size-cells", 2);
		buses[0] = buses[1] = bus;
		dt_prop_u32_list(dt, "bus-range", buses, 2);
		scan_phb(dt, bus);
		dt_end_node(dt);
		phb_num++;
	}
}

static void dt_finish(struct iseries_flat_dt *dt)
{
	dt_push_u32(dt, OF_DT_END);
	dt->header.totalsize = (unsigned long)dt_data - (unsigned long)dt;
	klimit = ALIGN((unsigned long)dt_data, 8);
}

void * __init build_flat_dt(unsigned long phys_mem_size)
{
	struct iseries_flat_dt *iseries_dt;
	u64 tmp[2];

	iseries_dt = dt_init();

	dt_start_node(iseries_dt, "");

	dt_prop_u32(iseries_dt, "#address-cells", 2);
	dt_prop_u32(iseries_dt, "#size-cells", 2);
	dt_model(iseries_dt);

	/* /memory */
	dt_start_node(iseries_dt, "memory@0");
	dt_prop_str(iseries_dt, "device_type", device_type_memory);
	tmp[0] = 0;
	tmp[1] = phys_mem_size;
	dt_prop_u64_list(iseries_dt, "reg", tmp, 2);
	dt_end_node(iseries_dt);

	/* /chosen */
	dt_start_node(iseries_dt, "chosen");
	dt_prop_str(iseries_dt, "bootargs", cmd_line);
	dt_initrd(iseries_dt);
	dt_end_node(iseries_dt);

	dt_cpus(iseries_dt);

	dt_vdevices(iseries_dt);
	dt_pci_devices(iseries_dt);

	dt_end_node(iseries_dt);

	dt_finish(iseries_dt);

	return iseries_dt;
}