blob: 76c07b0c3566cc4e37180895fb88682e882d2238 [file] [log] [blame] [edit]
/*
* Copyright (c) 2004 Picture Elements, Inc.
* Stephen Williams (steve@icarus.com)
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ident "$Id:$"
# include <common.h>
# include <pci.h>
# include "jse_priv.h"
/*
* The JSE board has an Intel 21555 non-transparent bridge for
* communication with the host. We need to render it harmless on the
* JSE side, but leave it alone on the host (primary) side. Normally,
* this will all be done before the host BIOS can gain access to the
* board, due to the Primary Access Lockout bit.
*
* The host_bridge_init function is called as a late initialization
* function, after most of the board is set up, including a PCI scan.
*/
void host_bridge_init (void)
{
/* The bridge chip is at a fixed location. */
pci_dev_t dev = PCI_BDF (0, 10, 0);
/* Set PCI Class code --
The primary side sees this class code at 0x08 in the
primary config space. This must be something other then a
bridge, or MS Windows starts doing weird stuff to me. */
pci_write_config_dword (dev, 0x48, 0x04800000);
/* Set subsystem ID --
The primary side sees this value at 0x2c. We set it here so
that the host can tell what sort of device this is:
We are a Picture Elements [0x12c5] JSE [0x008a]. */
pci_write_config_dword (dev, 0x6c, 0x008a12c5);
/* Downstream (Primary-to-Secondary) BARs are set up mostly
off. We need only the Memory-0 Bar so that the host can get
at the CSR region to set up tables and the lot. */
/* Downstream Memory 0 setup (4K for CSR) */
pci_write_config_dword (dev, 0xac, 0xfffff000);
/* Downstream Memory 1 setup (off) */
pci_write_config_dword (dev, 0xb0, 0x00000000);
/* Downstream Memory 2 setup (off) */
pci_write_config_dword (dev, 0xb4, 0x00000000);
/* Downstream Memory 3 setup (off) */
pci_write_config_dword (dev, 0xb8, 0x00000000);
/* Upstream (Secondary-to-Primary) BARs are used to get at
host memory from the JSE card. Create two regions: a small
one to manage individual word reads/writes, and a larger
one for doing bulk frame moves. */
/* Upstream Memory 0 Setup -- (BAR2) 4K non-prefetchable */
pci_write_config_dword (dev, 0xc4, 0xfffff000);
/* Upstream Memory 1 setup -- (BAR3) 4K non-prefetchable */
pci_write_config_dword (dev, 0xc8, 0xfffff000);
/* Upstream Memory 2 (BAR4) uses page translation, and is set
up in CCR1. Configure for 4K pages. */
/* Set CCR1,0 reigsters. This clears the Primary PCI Lockout
bit as well, so we are done configuring after this
point. Therefore, this must be the last step.
CC1[15:12]= 0 (disable I2O message unit)
CC1[11:8] = 0x5 (4K page size)
CC0[11] = 1 (Secondary Clock Disable: disable clock)
CC0[10] = 0 (Primary Access Lockout: allow primary access)
*/
pci_write_config_dword (dev, 0xcc, 0x05000800);
}