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/*
 *  for jz4740 usb boot
 *
 *  Copyright (c) 2009	Xiangfu Liu <xiangfu.z@gmail.com>
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */
    .set noreorder
    .globl usb_boot
    .text

//----------------------------------------------------------------------
// Both NAND and USB boot load data to D-Cache first, then transfer
// data from D-Cache to I-Cache, and jump to execute the code in I-Cache.
// So init caches first and then dispatch to a proper boot routine.
//----------------------------------------------------------------------

.macro load_addr reg addr
	li \reg, 0x80000000
	addiu \reg, \reg, \addr
	la $2, usbboot_begin
	subu \reg, \reg, $2
.endm

usb_boot:
	//--------------------------------------------------------------
	// Initialize PLL: set ICLK to 84MHz and HCLK to 42MHz.
	//--------------------------------------------------------------
	la	$9, 0xB0000000		// CPCCR: Clock Control Register
	la	$8, 0x42041110		// I:S:M:P=1:2:2:2
	sw	$8, 0($9)

	la	$9, 0xB0000010		// CPPCR: PLL Control Register
	la	$8, 0x06000120		// M=12 N=0 D=0 CLK=12*(M+2)/(N+2)
	sw	$8, 0($9)

	mtc0	$0, $26			// CP0_ERRCTL, restore WST reset state
	nop

	mtc0	$0, $16			// CP0_CONFIG
	nop

	// Relocate code to beginning of the ram

	la $2, usbboot_begin
	la $3, usbboot_end
	li $4, 0x80000000

1:
	lw $5, 0($2)
	sw $5, 0($4)
	addiu $2, $2, 4
	bne $2, $3, 1b
	addiu $4, $4, 4

	li $2, 0x80000000
	ori $3, $2, 0
	addiu $3, $3, usbboot_end
	la $4, usbboot_begin
	subu $3, $3, $4


2:
	cache	0x0, 0($2)		// Index_Invalidate_I
	cache	0x1, 0($2)		// Index_Writeback_Inv_D
	addiu	$2, $2, 32
	subu $4, $3, $2
	bgtz	$4, 2b
	nop

	load_addr $3, usb_boot_return

	jr $3

usbboot_begin:

init_caches:
	li	$2, 3			// cacheable for kseg0 access
	mtc0	$2, $16			// CP0_CONFIG
	nop

	li	$2, 0x20000000		// enable idx-store-data cache insn
	mtc0	$2, $26			// CP0_ERRCTL

	ori	$2, $28, 0		// start address
	ori	$3, $2, 0x3fe0		// end address, total 16KB
	mtc0	$0, $28, 0		// CP0_TAGLO
	mtc0	$0, $28, 1		// CP0_DATALO
cache_clear_a_line:
	cache	0x8, 0($2)		// Index_Store_Tag_I
	cache	0x9, 0($2)		// Index_Store_Tag_D
	bne	$2, $3, cache_clear_a_line
	addiu	$2, $2, 32		// increment CACHE_LINE_SIZE

	ori	$2, $28, 0		// start address
	ori	$3, $2, 0x3fe0		// end address, total 16KB
	la	$4, 0x1ffff000		// physical address and 4KB page mask
cache_alloc_a_line:
	and	$5, $2, $4
	ori	$5, $5, 1		// V bit of the physical tag
	mtc0	$5, $28, 0		// CP0_TAGLO
	cache	0x8, 0($2)		// Index_Store_Tag_I
	cache	0x9, 0($2)		// Index_Store_Tag_D
	bne	$2, $3, cache_alloc_a_line
	addiu	$2, $2, 32		// increment CACHE_LINE_SIZE

	nop
	nop
	nop
	//--------------------------------------------------------------
	// Transfer data from dcache to icache, then jump to icache.
	//
	// Input parameters:
	//
	// $19: data length in bytes
	// $20: jump target address
	//--------------------------------------------------------------
xfer_d2i:

	ori	$8, $20, 0
	addu	$9, $8, $19		// total 16KB

1:
	cache	0x0, 0($8)		// Index_Invalidate_I
	cache	0x1, 0($8)		// Index_Writeback_Inv_D
	bne	$8, $9, 1b
	addiu	$8, $8, 32

	// flush write-buffer
	sync

	// Invalidate BTB
	mfc0	$8, $16, 7		// CP0_CONFIG
	nop
	ori	$8, 2
	mtc0	$8, $16, 7
	nop

	// Overwrite config to disable ram initalisation
	li $2, 0xff
	sb $2, 20($20)

	jalr	$20
	nop

icache_return:
	//--------------------------------------------------------------
	// User code can return to here after executing itself in 
	// icache, by jumping to $31.
	//--------------------------------------------------------------
	b	usb_boot_return
	nop


usb_boot_return:
	//--------------------------------------------------------------
	// Enable the USB PHY
	//--------------------------------------------------------------
	la	$9, 0xB0000024		// CPM_SCR
	lw	$8, 0($9)
	ori	$8, 0x40		// USBPHY_ENABLE
	sw	$8, 0($9)

	//--------------------------------------------------------------
	// Initialize USB registers
	//--------------------------------------------------------------
	la	$27, 0xb3040000		// USB registers base address

	sb	$0, 0x0b($27)		// INTRUSBE: disable common USB interrupts
	sh	$0, 0x06($27)		// INTRINE: disable EPIN interrutps
	sh	$0, 0x08($27)		// INTROUTE: disable EPOUT interrutps

	li	$9, 0x61
	sb	$9, 0x01($27)		// POWER: HSENAB | SUSPENDM | SOFTCONN

	//--------------------------------------------------------------
	// Initialize USB states
	//--------------------------------------------------------------
	li	$22, 0			// set EP0 to IDLE state
	li	$23, 1			// no data stage

	//--------------------------------------------------------------
	// Main loop of polling the usb commands
	//--------------------------------------------------------------
usb_command_loop:
	lbu	$9, 0x0a($27)		// read INTRUSB
	andi	$9, 0x04		// check USB_INTR_RESET
	beqz	$9, check_intr_ep0in
	nop

	//--------------------------------------------------------------
 	// 1. Handle USB reset interrupt
	//--------------------------------------------------------------
handle_reset_intr:
	lbu	$9, 0x01($27)		// read POWER
	andi	$9, 0x10		// test HS_MODE
	bnez	$9, _usb_set_maxpktsize
	li	$9, 512			// max packet size of HS mode
	li	$9, 64			// max packet size of FS mode

_usb_set_maxpktsize:
	li	$8, 1
	sb	$8, 0x0e($27)		// set INDEX 1

	sh	$9, 0x10($27)		// INMAXP
	sb	$0, 0x13($27)		// INCSRH
	sh	$9, 0x14($27)		// OUTMAXP
	sb	$0, 0x17($27)		// OUTCSRH

_usb_flush_fifo:
	li	$8, 0x48		// INCSR_CDT && INCSR_FF
	sb	$8, 0x12($27)		// INCSR
	li	$8, 0x90		// OUTCSR_CDT && OUTCSR_FF
	sb	$8, 0x16($27)		// OUTCSR

	li	$22, 0			// set EP0 to IDLE state
	li	$23, 1			// no data stage

	//--------------------------------------------------------------
	// 2. Check and handle EP0 interrupt
	//--------------------------------------------------------------
check_intr_ep0in:
	lhu	$10, 0x02($27)		// read INTRIN
	andi	$9, $10, 0x1		// check EP0 interrupt
	beqz	$9, check_intr_ep1in
	nop

handle_ep0_intr:
	sb	$0, 0x0e($27)		// set INDEX 0
	lbu	$11, 0x12($27)		// read CSR0

	andi	$9, $11, 0x04		// check SENTSTALL
	beqz	$9, _ep0_setupend
	nop

_ep0_sentstall:
	andi	$9, $11, 0xdb
	sb	$9, 0x12($27)		// clear SENDSTALL and SENTSTALL
	li	$22, 0			// set EP0 to IDLE state

_ep0_setupend:
	andi	$9, $11, 0x10		// check SETUPEND
	beqz	$9, ep0_idle_state
	nop

	ori	$9, $11, 0x80
	sb	$9, 0x12($27)		// set SVDSETUPEND
	li	$22, 0			// set EP0 to IDLE state

ep0_idle_state:
	bnez	$22, ep0_tx_state
	nop

	//--------------------------------------------------------------
	// 2.1 Handle EP0 IDLE state interrupt
	//--------------------------------------------------------------
	andi	$9, $11, 0x01		// check OUTPKTRDY
	beqz	$9, check_intr_ep1in
	nop

	//--------------------------------------------------------------
	// Read 8-bytes setup packet from the FIFO
	//--------------------------------------------------------------
	lw	$25, 0x20($27)		// first word of setup packet
	lw	$26, 0x20($27)		// second word of setup packet

	andi	$9, $25, 0x60		// bRequestType & USB_TYPE_MASK
	beqz	$9, _ep0_std_req
	nop

	//--------------------------------------------------------------
	// 2.1.1 Vendor-specific setup request
	//--------------------------------------------------------------
_ep0_vend_req:
	li	$22, 0			// set EP0 to IDLE state
	li	$23, 1			// NoData = 1

	andi	$9, $25, 0xff00		// check bRequest
	srl	$9, $9, 8
	beqz	$9, __ep0_get_cpu_info
	sub	$8, $9, 0x1
	beqz	$8, __ep0_set_data_address
	sub	$8, $9, 0x2
	beqz	$8, __ep0_set_data_length
	sub	$8, $9, 0x3
	beqz	$8, __ep0_flush_caches
	sub	$8, $9, 0x4
	beqz	$8, __ep0_prog_start1
	sub	$8, $9, 0x5
	beqz	$8, __ep0_prog_start2
	nop
	b	_ep0_idle_state_fini	// invalid request
	nop

__ep0_get_cpu_info:
	load_addr $20, cpu_info_data	// data pointer to transfer
	li	$21, 8			// bytes left to transfer
	li	$22, 1			// set EP0 to TX state
	li	$23, 0			// NoData = 0

	b	_ep0_idle_state_fini
	nop

__ep0_set_data_address:
	li	$9, 0xffff0000
	and	$9, $25, $9
	andi	$8, $26, 0xffff
	or	$20, $9, $8		// data address of next transfer

	b	_ep0_idle_state_fini
	nop

__ep0_set_data_length:
	li	$9, 0xffff0000
	and	$9, $25, $9
	andi	$8, $26, 0xffff
	or	$21, $9, $8		// data length of next transfer

	li	$9, 0x48		// SVDOUTPKTRDY and DATAEND
	sb	$9, 0x12($27)		// CSR0

	// We must write packet to FIFO before EP1-IN interrupt here.
	b	handle_epin1_intr
	nop

__ep0_flush_caches:
	// Flush dcache and invalidate icache.
	li	$8, 0x80000000
	addi	$9, $8, 0x3fe0		// total 16KB

1:
	cache	0x0, 0($8)		// Index_Invalidate_I
	cache	0x1, 0($8)		// Index_Writeback_Inv_D
	bne	$8, $9, 1b
	addiu	$8, $8, 32

	// flush write-buffer
	sync

	// Invalidate BTB
	mfc0	$8, $16, 7		// CP0_CONFIG
	nop
	ori	$8, 2
	mtc0	$8, $16, 7
	nop

	b	_ep0_idle_state_fini
	nop

__ep0_prog_start1:
	li	$9, 0x48		// SVDOUTPKTRDY and DATAEND
	sb	$9, 0x12($27)		// CSR0

	li	$9, 0xffff0000
	and	$9, $25, $9
	andi	$8, $26, 0xffff
	or	$20, $9, $8		// target address

	b	xfer_d2i
	li	$19, 0x2000		// 16KB data length

__ep0_prog_start2:
	li	$9, 0x48		// SVDOUTPKTRDY and DATAEND
	sb	$9, 0x12($27)		// CSR0

	li	$9, 0xffff0000
	and	$9, $25, $9
	andi	$8, $26, 0xffff
	or	$20, $9, $8		// target address

	jalr	$20			// jump, and place the return address in $31
	nop

__ep0_prog_start2_return:
	// User code can return to here after executing itself, by jumping to $31.
	b	usb_boot_return
	nop

	//--------------------------------------------------------------
	// 2.1.2 Standard setup request
	//--------------------------------------------------------------
_ep0_std_req:
	andi	$12, $25, 0xff00	// check bRequest
	srl	$12, $12, 8
	sub	$9, $12, 0x05		// check USB_REQ_SET_ADDRESS
	bnez	$9, __ep0_req_set_config
	nop

	//--------------------------------------------------------------
	// Handle USB_REQ_SET_ADDRESS
	//--------------------------------------------------------------
__ep0_req_set_addr:
	srl	$9, $25, 16		// get wValue
	sb	$9, 0x0($27)		// set FADDR
	li	$23, 1			// NoData = 1
	b	_ep0_idle_state_fini
	nop

__ep0_req_set_config:
	sub	$9, $12, 0x09		// check USB_REQ_SET_CONFIGURATION
	bnez	$9, __ep0_req_get_desc
	nop

	//--------------------------------------------------------------
	// Handle USB_REQ_SET_CONFIGURATION
	//--------------------------------------------------------------
	li	$23, 1			// NoData = 1
	b	_ep0_idle_state_fini
	nop

__ep0_req_get_desc:
	sub	$9, $12, 0x06		// check USB_REQ_GET_DESCRIPTOR
	bnez	$9, _ep0_idle_state_fini
	li	$23, 1			// NoData = 1

	//--------------------------------------------------------------
	// Handle USB_REQ_GET_DESCRIPTOR
	//--------------------------------------------------------------
	li	$23, 0			// NoData = 0

	srl	$9, $25, 24		// wValue >> 8
	sub	$8, $9, 0x01		// check USB_DT_DEVICE
	beqz	$8, ___ep0_get_dev_desc
	srl	$21, $26, 16		// get wLength
	sub	$8, $9, 0x02		// check USB_DT_CONFIG
	beqz	$8, ___ep0_get_conf_desc
	sub	$8, $9, 0x03		// check USB_DT_STRING
	beqz	$8, ___ep0_get_string_desc
	sub	$8, $9, 0x06		// check USB_DT_DEVICE_QUALIFIER
	beqz	$8, ___ep0_get_dev_qualifier
	nop
	b	_ep0_idle_state_fini
	nop

___ep0_get_dev_desc:
	load_addr	$20, device_desc	// data pointer
	li	$22, 1			// set EP0 to TX state
	sub	$8, $21, 18
	blez	$8, _ep0_idle_state_fini // wLength <= 18
	nop
	li	$21, 18			// max length of device_desc
	b	_ep0_idle_state_fini
	nop

___ep0_get_dev_qualifier:
	load_addr	$20, dev_qualifier	// data pointer
	li	$22, 1			// set EP0 to TX state
	sub	$8, $21, 10
	blez	$8, _ep0_idle_state_fini // wLength <= 10
	nop
	li	$21, 10			// max length of dev_qualifier
	b	_ep0_idle_state_fini
	nop

___ep0_get_conf_desc:
	load_addr	$20, config_desc_fs	// data pointer of FS mode
	lbu	$8, 0x01($27)		// read POWER
	andi	$8, 0x10		// test HS_MODE
	beqz	$8, ___ep0_get_conf_desc2
	nop
	load_addr $20, config_desc_hs	// data pointer of HS mode

___ep0_get_conf_desc2:
	li	$22, 1			// set EP0 to TX state
	sub	$8, $21, 32
	blez	$8, _ep0_idle_state_fini // wLength <= 32
	nop
	li	$21, 32			// max length of config_desc
	b	_ep0_idle_state_fini
	nop

___ep0_get_string_desc:
	li	$22, 1			// set EP0 to TX state

	srl	$9, $25, 16		// wValue & 0xff
	andi	$9, 0xff

	sub	$8, $9, 1
	beqz	$8, ___ep0_get_string_manufacture
	sub	$8, $9, 2
	beqz	$8, ___ep0_get_string_product
	nop

___ep0_get_string_lang_ids:
	load_addr	$20, string_lang_ids	// data pointer
	b	_ep0_idle_state_fini
	li	$21, 4			// data length

___ep0_get_string_manufacture:
	load_addr	$20, string_manufacture	// data pointer
	b	_ep0_idle_state_fini
	li	$21, 16			// data length

___ep0_get_string_product:
	load_addr	$20, string_product	// data pointer
	b	_ep0_idle_state_fini
	li	$21, 46			// data length

_ep0_idle_state_fini:
	li	$9, 0x40		// SVDOUTPKTRDY
	beqz	$23, _ep0_idle_state_fini2
	nop
	ori	$9, $9, 0x08		// DATAEND
_ep0_idle_state_fini2:
	sb	$9, 0x12($27)		// CSR0
	beqz	$22, check_intr_ep1in
	nop

	//--------------------------------------------------------------
	// 2.2 Handle EP0 TX state interrupt
	//--------------------------------------------------------------
ep0_tx_state:
	sub	$9, $22, 1
	bnez	$9, check_intr_ep1in
	nop

	sub	$9, $21, 64		// max packetsize
	blez	$9, _ep0_tx_state2	// data count <= 64
	ori	$19, $21, 0
	li	$19, 64

_ep0_tx_state2:
	beqz	$19, _ep0_tx_state3	// send ZLP
	ori	$18, $19, 0		// record bytes to be transferred
	sub	$21, $21, $19		// decrement data count

_ep0_fifo_write_loop:
	lbu	$9, 0($20)		// read data
	sb	$9, 0x20($27)		// load FIFO
	sub	$19, $19, 1		// decrement counter
	bnez	$19, _ep0_fifo_write_loop
	addi	$20, $20, 1		// increment data pointer

	sub	$9, $18, 64		// max packetsize
	beqz	$9, _ep0_tx_state4
	nop

_ep0_tx_state3:
	// transferred bytes < max packetsize
	li	$9, 0x0a		// set INPKTRDY and DATAEND
	sb	$9, 0x12($27)		// CSR0
	li	$22, 0			// set EP0 to IDLE state
	b	check_intr_ep1in
	nop

_ep0_tx_state4:
	// transferred bytes == max packetsize
	li	$9, 0x02		// set INPKTRDY
	sb	$9, 0x12($27)		// CSR0
	b	check_intr_ep1in
	nop

	//--------------------------------------------------------------
	// 3. Check and handle EP1 BULK-IN interrupt
	//--------------------------------------------------------------
check_intr_ep1in:
	andi	$9, $10, 0x2		// check EP1 IN interrupt
	beqz	$9, check_intr_ep1out
	nop

handle_epin1_intr:
	li	$9, 1
	sb	$9, 0x0e($27)		// set INDEX 1
	lbu	$9, 0x12($27)		// read INCSR

	andi	$8, $9, 0x2		// check INCSR_FFNOTEMPT
	bnez	$8, _epin1_tx_state4
	nop

_epin1_write_fifo:
	lhu	$9, 0x10($27)		// get INMAXP
	sub	$8, $21, $9
	blez	$8, _epin1_tx_state1	// bytes left <= INMAXP
	ori	$19, $21, 0
	ori	$19, $9, 0

_epin1_tx_state1:
	beqz	$19, _epin1_tx_state4	// No data
	nop

	sub	$21, $21, $19		// decrement data count

	srl	$5, $19, 2		// # of word
	andi	$6, $19, 0x3		// # of byte
	beqz	$5, _epin1_tx_state2
	nop

_epin1_fifo_write_word:
	lw	$9, 0($20)		// read data from source address
	sw	$9, 0x24($27)		// write FIFO
	sub	$5, $5, 1		// decrement counter
	bnez	$5, _epin1_fifo_write_word
	addiu	$20, $20, 4		// increment dest address

_epin1_tx_state2:
	beqz	$6, _epin1_tx_state3
	nop

_epin1_fifo_write_byte:
	lbu	$9, 0($20)		// read data from source address
	sb	$9, 0x24($27)		// write FIFO
	sub	$6, $6, 1		// decrement counter
	bnez	$6, _epin1_fifo_write_byte
	addiu	$20, $20, 1		// increment dest address

_epin1_tx_state3:
	li	$9, 0x1
	sb	$9, 0x12($27)		// INCSR, set INPKTRDY

_epin1_tx_state4:
	// nop

	//--------------------------------------------------------------
	// 4. Check and handle EP1 BULK-OUT interrupt
	//--------------------------------------------------------------
check_intr_ep1out:
	lhu	$9, 0x04($27)		// read INTROUT
	andi	$9, 0x2
	beqz	$9, check_status_next
	nop

handle_epout1_intr:
	li	$9, 1
	sb	$9, 0x0e($27)		// set INDEX 1

	lbu	$9, 0x16($27)		// read OUTCSR
	andi	$9, 0x1			// check OUTPKTRDY
	beqz	$9, check_status_next
	nop

_epout1_read_fifo:
	lhu	$19, 0x18($27)		// read OUTCOUNT
	srl	$5, $19, 2		// # of word
	andi	$6, $19, 0x3		// # of byte
	beqz	$5, _epout1_rx_state1
	nop

_epout1_fifo_read_word:
	lw	$9, 0x24($27)		// read FIFO
	sw	$9, 0($20)		// store to dest address
	sub	$5, $5, 1		// decrement counter
	bnez	$5, _epout1_fifo_read_word
	addiu	$20, $20, 4		// increment dest address

_epout1_rx_state1:
	beqz	$6, _epout1_rx_state2
	nop

_epout1_fifo_read_byte:
	lbu	$9, 0x24($27)		// read FIFO
	sb	$9, 0($20)		// store to dest address
	sub	$6, $6, 1		// decrement counter
	bnez	$6, _epout1_fifo_read_byte
	addiu	$20, $20, 1		// increment dest address

_epout1_rx_state2:
	sb	$0, 0x16($27)		// clear OUTPKTRDY

check_status_next:
	b	usb_command_loop
	nop

//--------------------------------------------------------------
// Device/Configuration/Interface/Endpoint/String Descriptors
//--------------------------------------------------------------

	.align	2
device_desc:
	.byte	0x12		// bLength
	.byte	0x01		// bDescriptorType
	.byte	0x00		// bcdUSB
	.byte	0x02		// bcdUSB
	.byte	0x00		// bDeviceClass
	.byte	0x00		// bDeviceSubClass
	.byte	0x00		// bDeviceProtocol
	.byte	0x40		// bMaxPacketSize0
	.byte	0x1a		// idVendor
	.byte	0x60		// idVendor
	.byte	0x40		// idProduct
	.byte	0x47		// idProduct
	.byte	0x00		// bcdDevice
	.byte	0x01		// bcdDevice
	.byte	0x01		// iManufacturer
	.byte	0x02		// iProduct
	.byte	0x00		// iSerialNumber
	.byte	0x01		// bNumConfigurations

	.align	2
dev_qualifier:
	.byte	0x0a		// bLength
	.byte	0x06		// bDescriptorType
	.byte	0x00		// bcdUSB
	.byte	0x02		// bcdUSB
	.byte	0x00		// bDeviceClass
	.byte	0x00		// bDeviceSubClass
	.byte	0x00		// bDeviceProtocol
	.byte	0x40		// bMaxPacketSize0
	.byte	0x01		// bNumConfigurations
	.byte	0x00		// bRESERVED

	.align	2
config_desc_hs:
	.byte	0x09		// bLength
	.byte	0x02		// bDescriptorType
	.byte	0x20		// wTotalLength
	.byte	0x00		// wTotalLength
	.byte	0x01		// bNumInterfaces
	.byte	0x01		// bConfigurationValue
	.byte	0x00		// iConfiguration
	.byte	0xc0		// bmAttributes
	.byte	0x01		// MaxPower
intf_desc_hs:
	.byte	0x09		// bLength
	.byte	0x04		// bDescriptorType
	.byte	0x00		// bInterfaceNumber
	.byte	0x00		// bAlternateSetting
	.byte	0x02		// bNumEndpoints
	.byte	0xff		// bInterfaceClass
	.byte	0x00		// bInterfaceSubClass
	.byte	0x50		// bInterfaceProtocol
	.byte	0x00		// iInterface
ep1_desc_hs:
	.byte	0x07		// bLength
	.byte	0x05		// bDescriptorType
	.byte	0x01		// bEndpointAddress
	.byte	0x02		// bmAttributes
	.byte	0x00		// wMaxPacketSize
	.byte	0x02		// wMaxPacketSize
	.byte	0x00		// bInterval
ep2_desc_hs:
	.byte	0x07		// bLength
	.byte	0x05		// bDescriptorType
	.byte	0x81		// bEndpointAddress
	.byte	0x02		// bmAttributes
	.byte	0x00		// wMaxPacketSize
	.byte	0x02		// wMaxPacketSize
	.byte	0x00		// bInterval

	.align	2
config_desc_fs:
	.byte	0x09		// bLength
	.byte	0x02		// bDescriptorType
	.byte	0x20		// wTotalLength
	.byte	0x00		// wTotalLength
	.byte	0x01		// bNumInterfaces
	.byte	0x01		// bConfigurationValue
	.byte	0x00		// iConfiguration
	.byte	0xc0		// bmAttributes
	.byte	0x01		// MaxPower
intf_desc_fs:
	.byte	0x09		// bLength
	.byte	0x04		// bDescriptorType
	.byte	0x00		// bInterfaceNumber
	.byte	0x00		// bAlternateSetting
	.byte	0x02		// bNumEndpoints
	.byte	0xff		// bInterfaceClass
	.byte	0x00		// bInterfaceSubClass
	.byte	0x50		// bInterfaceProtocol
	.byte	0x00		// iInterface
ep1_desc_fs:
	.byte	0x07		// bLength
	.byte	0x05		// bDescriptorType
	.byte	0x01		// bEndpointAddress
	.byte	0x02		// bmAttributes
	.byte	0x40		// wMaxPacketSize
	.byte	0x00		// wMaxPacketSize
	.byte	0x00		// bInterval
ep2_desc_fs:
	.byte	0x07		// bLength
	.byte	0x05		// bDescriptorType
	.byte	0x81		// bEndpointAddress
	.byte	0x02		// bmAttributes
	.byte	0x40		// wMaxPacketSize
	.byte	0x00		// wMaxPacketSize
	.byte	0x00		// bInterval

	.align	2
string_lang_ids:
	.byte	0x04
	.byte	0x03
	.byte	0x09
	.byte	0x04

	.align	2
string_manufacture:
	.byte	0x10
	.byte	0x03
	.byte	0x49
	.byte	0x00
	.byte	0x6e
	.byte	0x00
	.byte	0x67
	.byte	0x00
	.byte	0x65
	.byte	0x00
	.byte	0x6e
	.byte	0x00
	.byte	0x69
	.byte	0x00
	.byte	0x63
	.byte	0x00

	.align	2
string_product:
	.byte	0x2e
	.byte	0x03
	.byte	0x4a
	.byte	0x00
	.byte	0x5a
	.byte	0x00
	.byte	0x34
	.byte	0x00
	.byte	0x37
	.byte	0x00
	.byte	0x34
	.byte	0x00
	.byte	0x30
	.byte	0x00
	.byte	0x20
	.byte	0x00
	.byte	0x55
	.byte	0x00
	.byte	0x53
	.byte	0x00
	.byte	0x42
	.byte	0x00
	.byte	0x20
	.byte	0x00
	.byte	0x42
	.byte	0x00
	.byte	0x6f
	.byte	0x00
	.byte	0x6f
	.byte	0x00
	.byte	0x74
	.byte	0x00
	.byte	0x20
	.byte	0x00
	.byte	0x44
	.byte	0x00
	.byte	0x65
	.byte	0x00
	.byte	0x76
	.byte	0x00
	.byte	0x69
	.byte	0x00
	.byte	0x63
	.byte	0x00
	.byte	0x65
	.byte	0x00

	.align	2
cpu_info_data:
	.byte	0x4a
	.byte	0x5a
	.byte	0x34
	.byte	0x37
	.byte	0x34
	.byte	0x30
	.byte	0x56
	.byte	0x31
usbboot_end:

    .set reorder