/*
* Copyright (c) 2011 Jan Vesely
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup drvusbohci
* @{
*/
/** @file
* @brief OHCI driver
*/
#ifndef DRV_OHCI_HW_STRUCT_TRANSFER_DESCRIPTOR_H
#define DRV_OHCI_HW_STRUCT_TRANSFER_DESCRIPTOR_H
#include <assert.h>
#include <stdbool.h>
#include <stdint.h>
#include "mem_access.h"
#include "completion_codes.h"
/*
* OHCI TDs can handle up to 8KB buffers, however, it can use max 2 pages.
* Using 4KB buffers guarantees the page count condition.
* (OHCI assumes 4KB pages)
*/
#define OHCI_TD_MAX_TRANSFER (4 * 1024)
/**
* Transfer Descriptor representation.
*
* See OHCI spec chapter 4.3.1 General Transfer Descriptor on page 19
* (pdf page 33) for details.
*/
typedef struct td {
/** Status field. Do not touch on active TDs. */
volatile uint32_t status;
#define TD_STATUS_ROUND_FLAG (1 << 18)
#define TD_STATUS_DP_MASK (0x3) /* Direction/PID */
#define TD_STATUS_DP_SHIFT (19)
#define TD_STATUS_DP_SETUP (0x0)
#define TD_STATUS_DP_OUT (0x1)
#define TD_STATUS_DP_IN (0x2)
#define TD_STATUS_DI_MASK (0x7) /* Delay interrupt, wait n frames before irq */
#define TD_STATUS_DI_SHIFT (21)
#define TD_STATUS_DI_NO_INTERRUPT (0x7)
#define TD_STATUS_T_FLAG (1 << 24) /* Explicit toggle bit value for this TD */
#define TD_STATUS_T_USE_TD_FLAG (1 << 25) /* 1 = use bit 24 as toggle bit */
#define TD_STATUS_EC_MASK (0x3) /* Error count */
#define TD_STATUS_EC_SHIFT (26)
#define TD_STATUS_CC_MASK (0xf) /* Condition code */
#define TD_STATUS_CC_SHIFT (28)
/**
* Current buffer pointer.
* Phys address of the first byte to be transferred.
*/
volatile uint32_t cbp;
/** Pointer to the next TD in chain. 16-byte aligned. */
volatile uint32_t next;
#define TD_NEXT_PTR_MASK (0xfffffff0)
#define TD_NEXT_PTR_SHIFT (0)
/**
* Buffer end.
* Phys address of the last byte of the transfer.
* @note this does not have to be on the same page as cbp.
*/
volatile uint32_t be;
} __attribute__((packed, aligned(32))) td_t;
void td_init(td_t *, const td_t *, usb_direction_t, const void *, size_t, int);
void td_set_next(td_t *, const td_t *);
/**
* Check TD for completion.
* @param instance TD structure.
* @return true if the TD was accessed and processed by hw, false otherwise.
*/
inline static bool td_is_finished(const td_t *instance)
{
assert(instance);
const int cc = (OHCI_MEM32_RD(instance->status) >> TD_STATUS_CC_SHIFT) &
TD_STATUS_CC_MASK;
/*
* This value is changed on transfer completion,
* either to CC_NOERROR or and error code.
* See OHCI spec 4.3.1.3.5 p. 23 (pdf 37)
*/
if (cc != CC_NOACCESS1 && cc != CC_NOACCESS2) {
return true;
}
return false;
}
/**
* Get error code that indicates transfer status.
* @param instance TD structure.
* @return Error code.
*/
static inline errno_t td_error(const td_t *instance)
{
assert(instance);
const int cc = (OHCI_MEM32_RD(instance->status) >>
TD_STATUS_CC_SHIFT) & TD_STATUS_CC_MASK;
return cc_to_rc(cc);
}
/**
* Get remaining portion of buffer to be read/written
* @param instance TD structure
* @return size of remaining buffer.
*/
static inline size_t td_remain_size(td_t *instance)
{
assert(instance);
/* Current buffer pointer is cleared on successful transfer */
if (instance->cbp == 0)
return 0;
/* Buffer end points to the last byte of transfer buffer, so add 1 */
return OHCI_MEM32_RD(instance->be) - OHCI_MEM32_RD(instance->cbp) + 1;
}
#endif
/**
* @}
*/