#pypp 0
// Iris: micro-kernel for a capability-based operating system.
// panic.ccp: Stop running and try to notify the user of the problem.
// Copyright 2009 Bas Wijnen <wijnen@debian.org>
//
// 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 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#define ARCH
#include "kernel.hh"

#ifdef USE_SERIAL
void kdebug (unsigned ch):
	while !(UART0_LSR & UARTLSR_TDRQ):
	UART0_TDR = ch
#else
void kdebug (unsigned ch):
	if !dbg_cap.valid () || dbg_code.l:
		return
	kCapability::Context c
	c.data[0] = ch
	++dbg_code.l
	dbg_cap->invoke (&c)
	--dbg_code.l
#endif

void kdebug (char const *str):
	while *str:
		kdebug (*str++)

void kdebug_num (unsigned num, unsigned digits):
	char const *encode = "0123456789abcdef"
	for unsigned i = 0; i < digits; ++i:
		kdebug (encode[(num >> (4 * ((digits - 1) - i))) & 0xf])
	return

#if 1 || defined (NDEBUG)
static void print_addr (char const *t, unsigned addr, bool last = false):
	kdebug (t)
	kdebug_num (addr)
	#if 1
	unsigned de = addr >> 21
	unsigned te = (addr >> 12) & ((1 << 9) - 1)
	if de < 0x400 && old_current && old_current->address_space->arch.directory && old_current->address_space->arch.directory[de]:
		kdebug ("; EntryLo = ")
		kdebug_num (old_current->address_space->arch.directory[de]->entrylo[te])
	else:
		kdebug ("; no directory or page table")
	if old_current && de < 0x400:
		cp0_set (CP0_ENTRY_HI, (addr & (PAGE_MASK << 1)) | old_current->address_space->arch.asid)
		__asm__ volatile ("tlbp")
		unsigned idx, hi
		cp0_get (CP0_INDEX, idx)
		kdebug ("; tlb index: ")
		if idx & (1 << 31):
			kdebug ("none\n")
		else:
			__asm__ volatile ("tlbr")
			kdebug_num (idx, 2)
			kdebug ("; EntryLo = ")
			unsigned lo
			cp0_get (CP0_ENTRY_LO0, lo)
			kdebug_num (lo)
			kdebug (":")
			cp0_get (CP0_ENTRY_LO1, lo)
			kdebug_num (lo)
			kdebug ("\n")
	else:
		kdebug ('\n')
	if addr >= 0x80000000 && addr < 0xc0000000:
		for int i = -4; i < 4; ++i:
			kdebug (" ")
			kdebug_num (((unsigned *)addr)[i])
		kdebug ("\n")
	#else
	kdebug (last ? '\n' : ';')
	#endif

static void panic_message (unsigned n, const char *line, char const *name, char const *message):
	unsigned vaddr, epc
	cp0_get (CP0_BAD_V_ADDR, vaddr)
	cp0_get (CP0_EPC, epc)
	#if 1
	unsigned addr
	print_addr ("BadVAddr: ", vaddr)
	if old_current:
		print_addr ("PC: ", old_current->pc)
	print_addr ("epc: ", epc, true)
	#endif
	kdebug ("Panic: caller = ")
	if old_current:
		kdebug_num (old_current->id, 2)
		kdebug (":")
	kdebug_num ((unsigned)old_current)
	if old_current:
		kdebug ('@')
		kdebug_num (old_current->pc)
	kdebug ("; ")
	kdebug (name)
	kdebug (':')
	kdebug (line)
	kdebug (": ")
	kdebug (message)
	kdebug ('/')
	kdebug_num (n)
	kdebug ("; debug: ")
	kdebug_num (dbg_code.h)
	kdebug (':')
	kdebug_num (dbg_code.l)
	kdebug ('\n')
	kdebug ("debug buffer:")
	unsigned b = dbg_buffer_head
	for unsigned i = 0; i < 16; ++i:
		kdebug ('\n')
		for unsigned j = 0; j < 2; ++j:
			kdebug (' ')
			kdebug_num (dbg_buffer[b])
			++b
			if b == 32:
				b = 0
	kdebug ('\n')

void panic_impl (unsigned n, const char *line, char const *name, char const *message):
	// Stop all threads.
	while first_scheduled:
		first_scheduled->unrun ()
	for kReceiver *r = first_alarm; r; r = r->next_alarm:
		if r->owner:
			r->owner->unrun ()
	for unsigned i = 0; i < 32; ++i:
		if arch_interrupt_receiver[i] && arch_interrupt_receiver[i]->owner:
			arch_interrupt_receiver[i]->owner->unrun ()
	#ifndef NDEBUG
	panic_message (n, line, name, message)
	// If a log capability is registered, run its owner.
	#ifndef USE_SERIAL
	if dbg_cap.valid () && dbg_cap->target->owner:
		dbg_cap->target->owner->run ()
		// Use the (now running) log thread to display the message.
	// If no log capability is registered, the machine just hangs.
	#else
	arch_reboot ()
	#endif
	#endif
#ifndef NDEBUG
void dbg_send (unsigned num, unsigned bits):
	kdebug ("Warning: ")
	kdebug_num (num)
	kdebug ('/')
	kdebug_num (bits)
	kdebug ('\n')
#endif
#else
void delay (unsigned ms):
	for unsigned t = 0; t < 8000 * ms; ++t:
		GPIO_GPDIR (0) = GPIO_GPDIR (0)

void set_leds (bool a, bool b):
	gpio_as_output (GPIO_NUM_PORT, GPIO_NUM)
	gpio_as_output (GPIO_CAPS_PORT, GPIO_CAPS)
	if a:
		GPIO_GPDR (GPIO_NUM_PORT) &= ~(1 << GPIO_NUM)
	else:
		GPIO_GPDR (GPIO_NUM_PORT) |= 1 << GPIO_NUM
	if b:
		GPIO_GPDR (GPIO_CAPS_PORT) &= ~(1 << GPIO_CAPS)
	else:
		GPIO_GPDR (GPIO_CAPS_PORT) |= 1 << GPIO_CAPS

void dbg_send (unsigned n, unsigned bits):
	for unsigned i = 0; i < bits; ++i:
		bool v = n & (1 << (bits - 1))
		set_leds (v, !v)
		delay (350)
		set_leds (false, false)
		delay (150)
		n <<= 1
	set_leds (true, true)
	delay (50)
	set_leds (false, false)
	delay (50)
void panic_impl (unsigned n, const char *line, char const *name, char const *message):
	unsigned epc
	cp0_get (CP0_EPC, epc)
	dbg_send (epc, 32)
	while true:
		dbg_send (n, 32)
#endif