#pypp 0
// Iris: micro-kernel for a capability-based operating system.
// boot-programs/lcd.ccp: Display driver.
// 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/>.

#include "devices.hh"
#define ARCH
#include "arch.hh"

__asm__ volatile (".section .rodata\n.globl charset\ncharset:\n.incbin \"source/charset.data\"\n.section .text")
extern unsigned char const charset[127-32][8][6]

#define assert(x) do { if (!(x)) { kdebug ("assertion failed " #x); while (true) {} } } while (0)

#if defined (TRENDTAC)
static unsigned h = 800, v = 480, fps = 60, Bpp = 2
#define LOG_X_BASE 1
#define LOG_Y_BASE 1
#elif defined (NANONOTE)
static unsigned h = 320, v = 240, fps = 60, Bpp = 4
#define LOG_X_BASE 0
#define LOG_Y_BASE 0
#else
#error unknown board
#endif
#define frame_size (v * h * Bpp)

static unsigned physical_descriptor

/**/struct Descriptor {
	unsigned next;
	unsigned frame;
	unsigned id;
	unsigned cmd;
 } __attribute__ ((packed))

#if defined (NANONOTE)
#define SP_PORT 2
#define SPEN 21
#define SPDA 22
#define SPCK 23

static void udelay (unsigned num):
	for unsigned i = 0; i < num * (JZ_EXTAL / 1000000); ++i:
		// set 0 does nothing, but costs at least one clock pulse.
		gpio_set (SP_PORT, 0)

// Register names.  The registers are not named in the datasheet, and in some cases the name only describes a part of the bits in it.
// The registers with bit 6 set have bit 7 set instead, because of the transfer method.
enum spi_reg:
	AC		= 0x00
	DC		= 0x01
	BRIGHTNESS	= 0x03
	FORMAT		= 0x04
	BACKLIGHT1	= 0x05
	VBLANK		= 0x06
	HBLANK		= 0x07
	BACKLIGHT2	= 0x08
	SYNC		= 0x0b
	POLARITY	= 0x0c
	CONTRAST_RGB	= 0x0d
	SUB_CONTRAST_R	= 0x0e
	SUB_BRIGHTNESS_R= 0x0f
	SUB_CONTRAST_B	= 0x10
	SUB_BRIGHTNESS_B= 0x11
	TRIM		= 0x12
	COLOR		= 0x13
	GAMMA		= 0x16
	GAMMA1		= 0x17
	GAMMA2		= 0x18
	GAMMA3		= 0x19
	GAMMA4		= 0x1a
	INVERSION	= 0xa5
	HLEVEL		= 0xa6
	LLEVEL		= 0xa7
	FB		= 0xb1

static void write_reg (unsigned reg, unsigned val):
	unsigned value = (reg << 8) | (val & 0xff)
	gpio_clear (SP_PORT, 1 << SPEN)
	udelay (1)
	for unsigned i = 0; i < 16; ++i, value <<= 1:
		gpio_clear (SP_PORT, 1 << SPCK)
		if value & 0x8000:
			gpio_set (SP_PORT, 1 << SPDA)
		else:
			gpio_clear (SP_PORT, 1 << SPDA)
		udelay (4)
		gpio_set (SP_PORT, 1 << SPCK)
		udelay (4)
	gpio_set (SP_PORT, 1 << SPEN)
	udelay(4)
#endif

static void reset ():
	#if defined (TRENDTAC)
	// Note that the sync pulse is part of the pre-display region.
	// Vertical timings.
	unsigned vsync = 20, vpre = 20, vpost = 0
	// Horizontal timings.
	unsigned hsync = 80, hpre = 80, hpost = 0

	// One clock pulse per pixel.
	unsigned cpp = 1
	// Bits per pixel.
	unsigned bpp = LCD_CTRL_BPP_16
	// Configuration.
	#define MODE_TFT_GEN 0
	#define VSYNC_N (1 << 8)
	unsigned cfg = MODE_TFT_GEN | VSYNC_N
	#elif defined (NANONOTE)
	// Note that the sync pulse is part of the pre-display region.
	// Horizontal timings.
	unsigned hsync = 1, hpre = 70, hpost = 273
	// Vertical timings.
	unsigned vsync = 1, vpre = 21, vpost = 2
	// 3 clocks per pixel.
	unsigned cpp = 3
	// Bits per pixel.
	unsigned bpp = LCD_CTRL_BPP_18_24
	// Configuration.
	unsigned cfg = LCD_CFG_MODE_SERIAL_TFT | LCD_CFG_HSP | LCD_CFG_VSP | LCD_CFG_PCP
	// Set up SPI pins.
	gpio_as_output (SP_PORT, (1 << SPEN) | (1 << SPCK) | (1 << SPDA))
	gpio_set (SP_PORT, (1 << SPEN) | (1 << SPCK))
	#else
	#error unknown board
	#endif

	// Note that the sync pulse is part of the pre-display region.
	unsigned vpe = vsync, vds = vpre, vde = vds + v, vt = vde + vpost
	unsigned hpe = hsync, hds = hpre, hde = hds + h, ht = hde + hpost

	cpm_stop_lcd ()

	unsigned pixclock = fps * ht * vt

	#if defined (TRENDTAC)
	unsigned pllout = cpm_get_pllout ()
	CPM_CFCR2 = pllout / pixclock - 1

	unsigned val = pllout / (pixclock * 4) - 1
	assert (pllout / (val + 1) <= 150000000)
	assert (val <= 0xf)
	cpm_set_lcdclk_div (val)
	CPM_CFCR |= CPM_CFCR_UPE
	#elif defined (NANONOTE)
	unsigned val = cpm_get_pllout2 () / pixclock - 1
	//assert (val < 0x400)
	//cpm_set_pixdiv (val)
	//cpm_set_pixdiv (12)

	val = cpm_get_pllout2 () / (pixclock * 3) - 1
	assert (val < 0x20)
	//cpm_set_ldiv (val)
	// Update dividers.
	//CPM_CPCCR |= CPM_CPCCR_CE
	#else
	#error "Unknown board"
	#endif

	cpm_start_lcd ()

	#ifdef NANONOTE
	// Reset the controller.
	write_reg (BACKLIGHT1, 0x1e)
	// Enable display.
	write_reg (BACKLIGHT1, 0x5f)
	// Set data to rgbrgbrgb input, with a delta color filter.
	write_reg (COLOR, 0x01)
	#endif

	LCD_CTRL = (bpp << LCD_CTRL_BPP_BIT) | LCD_CTRL_BST_16
	LCD_CFG = cfg
	LCD_HSYNC = hpe
	LCD_VSYNC = vpe
	LCD_VAT = (ht << 16) | vt
	LCD_DAH = (hds << 16) | hde
	LCD_DAV = (vds << 16) | vde
	LCD_DA0 = physical_descriptor
	LCD_CTRL = (bpp << LCD_CTRL_BPP_BIT) | LCD_CTRL_BST_16 | LCD_CTRL_ENA
	//lcd_enable_eof_intr ()

static void putchar (unsigned x, unsigned y, unsigned ch):
	if ch < 32 || ch > 126:
		ch = 127
	ch -= 32
	for unsigned k = 0; k < 6; ++k:
		for unsigned r = 0; r < 8; ++r:
			LCD_FRAMEBUFFER_BASE[(y * 8 + r) * h + x * 6 + k] = charset[ch][r][k] * 0x00010101


static unsigned log_x = LOG_X_BASE, log_y = LOG_Y_BASE
static void inc_logx ():
	if ++log_x >= h / 6:
		log_x = LOG_X_BASE
		if ++log_y >= v / 8:
			log_y = LOG_Y_BASE

static void log_char (unsigned ch):
	switch ch:
		case '\n':
			while log_x < h / 6:
				putchar (log_x++, log_y, ' ')
			inc_logx ()
			break
		default:
			putchar (log_x, log_y, ch)
			inc_logx ()

static void log_str (char const *str):
	while *str:
		log_char (*str++)

static void log_num (Kernel::Num n):
	char const *encode = "0123456789abcdef"
	log_char ('[')
	for unsigned i = 0; i < 8; ++i:
		log_char (encode[(n.h >> (4 * (7 - i))) & 0xf])
	log_char (' ')
	for unsigned i = 0; i < 8; ++i:
		log_char (encode[(n.l >> (4 * (7 - i))) & 0xf])
	log_char (']')

static void log_msg ():
	log_str ("prot:")
	log_num (Kernel::recv.protected_data)
	log_str ("data:")
	for unsigned i = 0; i < 2; ++i:
		log_num (Kernel::recv.data[i])
	log_char ('\n')

enum captype:
	LOG = 32
	SET_EOF_CB
	BACKLIGHT

static unsigned spot (unsigned x, unsigned y, unsigned cx, unsigned cy):
	unsigned dx2 = (x - cx) * (x - cx)
	unsigned dy2 = (y - cy) * (y - cy)
	unsigned d2 = dx2 + dy2
	unsigned l = 120
	if d2 >= l * l:
		return 0
	return ((l * l - d2 - 1) << 8) / (l * l)

Kernel::Num start ():
	Kernel::schedule ()
	map_lcd ()
	map_cpm ()
	#ifdef NANONOTE
	map_gpio ()
	#endif

	Descriptor descriptor __attribute__ ((aligned (16)))
	unsigned pages = (frame_size + ~PAGE_MASK) >> PAGE_BITS
	unsigned physical = Kernel::my_memory.alloc_range (pages)
	assert (physical & PAGE_MASK && ~physical)
	for unsigned i = 0; i < pages; ++i:
		Kernel::Page p = Kernel::my_memory.create_page ()
		p.alloc_physical (physical + (i << PAGE_BITS), false, true)
		Kernel::my_memory.map (p, (unsigned)LCD_FRAMEBUFFER_BASE + (i << PAGE_BITS))
		Kernel::free_cap (p)
	for unsigned y = 0; y < v; ++y:
		for unsigned x = 0; x < h; ++x:
			unsigned r = spot (x, y, 100, 160)
			unsigned g = spot (x, y, 160, 60)
			unsigned b = spot (x, y, 220, 160)
			#if defined (TRENDTAC)
			LCD_FRAMEBUFFER_BASE[y * h + x] = ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3)
			#elif defined (NANONOTE)
			LCD_FRAMEBUFFER_BASE[y * h + x] = (r << 16) | (g << 8) | b
			#else
			#error "Define your framebuffer format."
			#endif
	Kernel::Page p = Kernel::my_memory.mapping (&descriptor)
	unsigned paddr = p.physical_address ()
	physical_descriptor = paddr + ((unsigned)&descriptor & ~PAGE_MASK)
	Kernel::free_cap (p)
	descriptor.next = physical_descriptor
	descriptor.frame = physical
	descriptor.id = 0xdeadbeef
	descriptor.cmd = LCD_CMD_EOFINT | ((frame_size / 4) << LCD_CMD_LEN_BIT)
	unsigned dptr = (unsigned)&descriptor
	__asm__ volatile ("lw $a0, %0\ncache 0x15, 0($a0)" :: "m"(dptr) : "memory", "a0")
	reset ()

	#if defined (TRENDTAC)
	Kernel::Cap logcap = Kernel::my_receiver.create_capability (LOG)
	__asm__ volatile ("li $a0, 1\nlw $a1, %0\nbreak" :: "m"(logcap.code): "a0", "a1", "memory")
	#endif

	// Register the backlight device.
	Kernel::Cap backlight = Kernel::my_receiver.create_capability (BACKLIGHT)
	Kernel::my_parent.provide_device <Setting> (backlight)

	Kernel::Cap eof_cb
	bool have_eof = false
	bool is_on = true
	unsigned backlight_user = 0
	Kernel::Num current_backlight = 0
	Kernel::my_parent.init_done ()
	while true:
		Kernel::wait ()
		//log_msg ()
		switch Kernel::recv.protected_data.h:
			case 0:
				switch Kernel::recv.protected_data.l:
					case IRQ_LCD:
						lcd_clr_eof ()
						eof_cb.invoke ()
						have_eof = false
						Kernel::free_cap (eof_cb)
						break
					#if defined (TRENDTAC)
					case LOG:
						log_char (Kernel::recv.data[0].l)
						break
					#endif
					case BACKLIGHT:
						switch Kernel::recv.data[0].l:
							case Device::CREATE_USER:
								Kernel::Cap reply = Kernel::get_reply ()
								Kernel::Cap c = Kernel::my_receiver.create_capability (Kernel::Num (backlight_user++, BACKLIGHT))
								reply.invoke (0, 0, c.copy ())
								Kernel::free_cap (c)
								Kernel::free_cap (reply)
								break
							case Device::DESTROY_USER:
								Kernel::recv.reply.invoke ()
								break
							case Device::USE:
								Kernel::Cap reply = Kernel::get_reply ()
								Kernel::Cap arg = Kernel::get_arg ()
								current_backlight = Kernel::my_receiver.get_protected (arg)
								reply.invoke ()
								Kernel::free_cap (arg)
								Kernel::free_cap (reply)
								break
							case Device::UNUSE:
								Kernel::Cap reply = Kernel::get_reply ()
								Kernel::Cap arg = Kernel::get_arg ()
								if current_backlight.value () == Kernel::my_receiver.get_protected (arg).value ():
									current_backlight = 0
								reply.invoke ()
								Kernel::free_cap (arg)
								Kernel::free_cap (reply)
								break
							default:
								log_char ('@')
								break
						break
					default:
						log_char ('#')
						log_num (Kernel::recv.protected_data)
						log_char ('\n')
						break
				break
			case BACKLIGHT:
				if current_backlight.value () != Kernel::recv.protected_data.value ():
					log_char ('&')
					log_num (current_backlight)
					log_num (Kernel::recv.protected_data)
					log_char ('\n')
					break
				switch Kernel::recv.data[0].l:
					case Setting::SET:
						// TODO
						unsigned state = Kernel::recv.data[1].l
						if !state:
							#if defined (NANONOTE)
							if is_on:
								write_reg (BACKLIGHT1, 0x5e)
								is_on = false
							#else
							#endif
						else:
							#if defined (NANONOTE)
							if !is_on:
								write_reg (BACKLIGHT1, 0x5f)
								is_on = true
							#else
							#endif
						Kernel::recv.reply.invoke ()
						break
					case Setting::GET_RANGE:
						Kernel::recv.reply.invoke (~0)
						break
					default:
						log_char ('$')
						break
				break
			case SET_EOF_CB:
				Kernel::Cap reply = Kernel::get_reply ()
				if have_eof:
					Kernel::free_cap (eof_cb)
				else:
					Kernel::register_interrupt (IRQ_LCD)
					have_eof = true
				eof_cb = Kernel::get_arg ()
				reply.invoke ()
				Kernel::free_cap (reply)
				break
			default:
				log_char ('~')
				log_num (Kernel::recv.protected_data)
				log_char ('\n')
				break