swarm_pci.c

一个很好的嵌入式linux平台下的bootloader

/*  *********************************************************************
    *  Broadcom Common Firmware Environment (CFE)
    *  
    *  Board device initialization		File: swarm_pci.c
    *  
    *  This is the part of the board support package for boards
    *  that support PCI. It describes the board-specific slots/devices
    *  and wiring thereof.
    *  
    *********************************************************************  
    *
    *  Copyright 2000,2001,2002,2003
    *  Broadcom Corporation. All rights reserved.
    *  
    *  This software is furnished under license and may be used and 
    *  copied only in accordance with the following terms and 
    *  conditions.  Subject to these conditions, you may download, 
    *  copy, install, use, modify and distribute modified or unmodified 
    *  copies of this software in source and/or binary form.  No title 
    *  or ownership is transferred hereby.
    *  
    *  1) Any source code used, modified or distributed must reproduce 
    *     and retain this copyright notice and list of conditions 
    *     as they appear in the source file.
    *  
    *  2) No right is granted to use any trade name, trademark, or 
    *     logo of Broadcom Corporation.  The "Broadcom Corporation" 
    *     name may not be used to endorse or promote products derived 
    *     from this software without the prior written permission of 
    *     Broadcom Corporation.
    *  
    *  3) THIS SOFTWARE IS PROVIDED "AS-IS" AND ANY EXPRESS OR
    *     IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED
    *     WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR 
    *     PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT 
    *     SHALL BROADCOM BE LIABLE FOR ANY DAMAGES WHATSOEVER, AND IN 
    *     PARTICULAR, BROADCOM SHALL NOT BE LIABLE FOR 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), EVEN IF ADVISED OF 
    *     THE POSSIBILITY OF SUCH DAMAGE.
    ********************************************************************* */

#include "lib_types.h"

#include "pcireg.h"
#include "pcivar.h"
#include "pci_internal.h"

/* PCI interrupt mapping on the BCM912500 (SWARM) board:
   Only device ids 5 and 6 are implemented as PCI connectors, and
   the only on-board device has id 7 (USB bridge).

   Slot    IDSEL   DevID  INT{A,B,C,D}   shift
  (PHB)      -       0       {A,-,-,-}     0
  (LHB)      -       1       {-,-,-,-}     0
    0       16       5       {A,B,C,D}     0 (identity)
    1       17       6       {B,C,D,A}     1 (A->B, B->C, C->D, D->A)
  (USB)     18       7       {C,D,-,-}     2 (A->C, B->D, C->A, D->B)
    -                                      3 (A->D, B->A, C->B, D->C) 

   Device 1 is the LDT host bridge.  By giving it a shift of 0,
   the normal rotation algorithm gives the correct result for devices
   on the secondary bus of the LDT host bridge (bus 1).  Firmware
   must program the API 10ll LDT-PCI bridge so that the normal
   rotation algorithm gives correct results for its secondary (bus 2):

    0       16       0       {A,B,C,D}     0 (identity)
    1       17       1       {B,C,D,A}     1 (A->B, B->C, C->D, D->A)
*/

extern int _pciverbose;

/* Return the base shift of a slot or device on the motherboard.
   This is board specific, for the SWARM (BCM912500E) only. */
uint8_t
pci_int_shift_0(pcitag_t tag)
{
    int bus, device;

    pci_break_tag(tag, NULL, &bus, &device, NULL);

    if (bus != 0)
	return 0;
    switch (device) {
    case 0:
	return 0;
    case 5: case 6: case 7:
        return ((device - 5) % 4);
    default:
	return 0;
    }
}

/* Return the mapping of a SWARM device/function interrupt to an
   interrupt line.  For the SB-1250, return 1-4 to indicate the
   pci_inta - pci_intd inputs to the interrupt mapper, respectively,
   or 0 if there is no mapping.  This is board specific, and the
   version below is for SWARM (BCM912500E), 32-bit slots only. */
uint8_t
pci_int_map_0(pcitag_t tag)
{
    pcireg_t data;
    int pin, bus, device;

    data = pci_conf_read(tag, PCI_BPARAM_INTERRUPT_REG);
    pin = PCI_INTERRUPT_PIN(data);
    if (pin == 0) {
	/* No IRQ used. */
	return 0;
    }
    if (pin > 4) {
	if (_pciverbose >= 1)
	    pci_tagprintf(tag, "pci_map_int: bad interrupt pin %d\n", pin);
	return 0;
    }

    pci_break_tag(tag, NULL, &bus, &device, NULL);

    if (bus != 0)
	return 0;

    switch (device) {
    case 0:
    case 5: case 6: case 7:
        return (((pin - 1) + pci_int_shift_0(tag)) % 4) + 1;
    default:
        return 0;
    }
}