iris/source/nand.ccp

#pypp 0
// Iris: micro-kernel for a capability-based operating system.
// boot-programs/nand.ccp: NAND 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"

#define debug Iris::debug
#define DELAY Iris::schedule
#include "nand.hh"
#undef debug

static unsigned *cache
static bool dirty
static unsigned current_block

static void sync ():
	Iris::debug ("erasing %x\n", current_block << block_bits)
	erase (current_block << block_bits)
	for unsigned p = 0; p < 1 << (block_bits - page_bits); ++p:
		write ((current_block << block_bits) + (p << page_bits), (char *)&cache[p << (page_bits - 2)])

static void read_block (unsigned b):
	if b == current_block:
		return
	if current_block != ~0 && dirty:
		sync ()
	current_block = b
	//kdebug ("setting current block to ")
	//kdebug_num (b)
	//kdebug ("\n")
	for unsigned p = 0; p < 1 << (block_bits - 9); ++p:
		read ((b << block_bits) + (p << 9), (char *)&cache[p << (9 - 2)])
	dirty = false

Iris::Num start ():
	map_emc ()
	map_gpio ()

	// Arbitrary addresses where the pages are mapped.
	command = (volatile char *)0x15000
	address = (volatile char *)0x16000
	data = (volatile char *)0x17000

	Iris::Page data_page = Iris::my_memory.create_page ()
	Iris::Page command_page = Iris::my_memory.create_page ()
	Iris::Page address_page = Iris::my_memory.create_page ()

	unsigned base = 0x18000000
	data_page.alloc_physical (base, false, false)
	command_page.alloc_physical (base + 0x8000, false, false)
	address_page.alloc_physical (base + 0x10000, false, false)

	Iris::my_memory.map (data_page, (unsigned)data)
	Iris::my_memory.map (command_page, (unsigned)command)
	Iris::my_memory.map (address_page, (unsigned)address)

	Iris::free_cap (data_page)
	Iris::free_cap (command_page)
	Iris::free_cap (address_page)

	reset ()

	current_block = ~0
	dirty = false
	cache = (unsigned *)0x40000000
	for unsigned p = 0; p < 1 << (block_bits - PAGE_BITS); ++p:
		Iris::Page page = Iris::my_memory.create_page ()
		page.set_flags (Iris::Page::PAYING | Iris::Page::FRAME)
		Iris::my_memory.map (page, (unsigned)cache + (p << PAGE_BITS))
		Iris::free_cap (page)
	Iris::Page tmp = Iris::my_memory.create_page ()
	tmp.set_flags (Iris::Page::PAYING)
	unsigned *tmp_addr = (unsigned *)0x3ffff000
	Iris::my_memory.map (tmp, (unsigned)tmp_addr)

	Iris::Cap cap = Iris::my_receiver.create_capability (0)
	Iris::my_parent.provide_capability <Iris::WString> (cap.copy ())
	Iris::free_cap (cap)

	Iris::my_parent.init_done ()

	while true:
		Iris::wait ()
		switch Iris::recv.data[0].l:
			case Iris::Block::GET_SIZE:
				if size_bits > 32:
					Iris::recv.reply.invoke (Iris::Num (0, 1 << (size_bits - 32)))
				else:
					Iris::recv.reply.invoke (1 << size_bits)
				break
			case Iris::Block::GET_ALIGN_BITS:
				Iris::recv.reply.invoke (9)
				break
			case Iris::Block::GET_BLOCK:
				unsigned row = Iris::recv.data[1].value () >> 9
				unsigned block = row >> (block_bits - 9)
				row &= (1 << (block_bits - 9)) - 1
				unsigned offset = Iris::recv.data[0].h & 0xe00
				unsigned size = Iris::recv.data[0].h >> 16
				if size + offset >= 0x1000:
					size = 0x1000 - offset
				#if 0
				kdebug ("get ")
				kdebug_num (block)
				kdebug (":")
				kdebug_num (row)
				kdebug ("+")
				kdebug_num (size)
				kdebug ("@")
				kdebug_num (offset)
				kdebug ("\n")
				#endif
				read_block (block)
				Iris::Cap reply = Iris::get_reply ()
				Iris::Page page = Iris::get_arg ()
				page.share (tmp)
				tmp.set_flags (Iris::Page::FRAME)
				for unsigned t = 0; t < size >> 2; ++t:
					tmp_addr[(offset >> 2) + t] = cache[t + (row << (9 - 2))]
				tmp.set_flags (0, Iris::Page::FRAME)
				reply.invoke ()
				Iris::free_cap (reply)
				Iris::free_cap (page)
				break
			case Iris::WBlock::SET_BLOCK:
				unsigned row = Iris::recv.data[1].value () >> 9
				unsigned block = row >> (block_bits - 9)
				row &= (1 << (block_bits - 9)) - 1
				unsigned offset = Iris::recv.data[0].h & 0xe00
				unsigned size = Iris::recv.data[0].h >> 16
				if size + offset >= 0x1000:
					size = 0x1000 - offset
				#if 0
				kdebug ("set ")
				kdebug_num (block)
				kdebug (":")
				kdebug_num (row)
				kdebug ("+")
				kdebug_num (size)
				kdebug ("@")
				kdebug_num (offset)
				kdebug ("\n")
				#endif
				//kdebug_num (current_block)
				//kdebug ("/")
				read_block (block)
				Iris::Cap reply = Iris::get_reply ()
				Iris::Page page = Iris::get_arg ()
				page.share (tmp)
				tmp.set_flags (Iris::Page::FRAME)
				for unsigned t = 0; t < size; t += 4:
					cache[(offset + t + (row << 9)) >> 2] = tmp_addr[(offset + t) >> 2]
				tmp.set_flags (0, Iris::Page::FRAME)
				reply.invoke ()
				Iris::free_cap (reply)
				Iris::free_cap (page)
				dirty = true
				//kdebug_num (current_block)
				//kdebug ("!")
				break
			case Iris::WBlock::TRUNCATE:
			default:
				Iris::recv.reply.invoke (Iris::ERR_INVALID_OPERATION)
				break