u-boot/drivers/pci/pci_mpc85xx.c
Pali Rohár c06597ff11 pci: mpc85xx: Do not access PCI BARs registers of BDF address 00:00.0
At BDF address 00:00.0 is fictional device which PCI configuration header
is for configuring mpc85xx PCI controller itself. PCI config space of this
device has ATMU inbound registers on position of PCI BARs. Trying to do PCI
auto configuration of this device cause rewriting ATMU inbound registers.
To avoid it, do not allow overwriting registers at BARs positions. And
because this device does not have any PCI memory, return zeros when trying
to read PCI BARs config space registers. It signals to auto configuration
tool to not allocate any PCI memory for this device.

This information is taken from MPC8544E Reference Manual, sections
17.3.1.3, 17.3.1.1.1, 17.3.2 and 17.3.2.11. Available at NXP website:
https://www.nxp.com/docs/en/reference-manual/MPC8544ERM.pdf

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
Tested-by: Heiko Schocher <hs@denx.de>
2023-05-01 18:59:33 -04:00

204 lines
5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* (C) Copyright 2019
* Heiko Schocher, DENX Software Engineering, hs@denx.de.
*
*/
#include <common.h>
#include <asm/bitops.h>
#include <pci.h>
#include <dm.h>
#include <asm/fsl_law.h>
struct mpc85xx_pci_priv {
void __iomem *cfg_addr;
void __iomem *cfg_data;
};
static int mpc85xx_pci_dm_read_config(const struct udevice *dev, pci_dev_t bdf,
uint offset, ulong *value,
enum pci_size_t size)
{
struct mpc85xx_pci_priv *priv = dev_get_priv(dev);
u32 addr;
if (offset > 0xff) {
*value = pci_get_ff(size);
return 0;
}
/* Skip mpc85xx PCI controller's ATMU inbound registers */
if (PCI_BUS(bdf) == 0 && PCI_DEV(bdf) == 0 && PCI_FUNC(bdf) == 0 &&
(offset & ~3) >= PCI_BASE_ADDRESS_0 && (offset & ~3) <= PCI_BASE_ADDRESS_5) {
*value = 0;
return 0;
}
addr = PCI_CONF1_ADDRESS(PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf), offset);
out_be32(priv->cfg_addr, addr);
sync();
switch (size) {
case PCI_SIZE_8:
*value = in_8(priv->cfg_data + (offset & 3));
break;
case PCI_SIZE_16:
*value = in_le16(priv->cfg_data + (offset & 2));
break;
case PCI_SIZE_32:
*value = in_le32(priv->cfg_data);
break;
}
return 0;
}
static int mpc85xx_pci_dm_write_config(struct udevice *dev, pci_dev_t bdf,
uint offset, ulong value,
enum pci_size_t size)
{
struct mpc85xx_pci_priv *priv = dev_get_priv(dev);
u32 addr;
if (offset > 0xff)
return 0;
/* Skip mpc85xx PCI controller's ATMU inbound registers */
if (PCI_BUS(bdf) == 0 && PCI_DEV(bdf) == 0 && PCI_FUNC(bdf) == 0 &&
(offset & ~3) >= PCI_BASE_ADDRESS_0 && (offset & ~3) <= PCI_BASE_ADDRESS_5)
return 0;
addr = PCI_CONF1_ADDRESS(PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf), offset);
out_be32(priv->cfg_addr, addr);
sync();
switch (size) {
case PCI_SIZE_8:
out_8(priv->cfg_data + (offset & 3), value);
break;
case PCI_SIZE_16:
out_le16(priv->cfg_data + (offset & 2), value);
break;
case PCI_SIZE_32:
out_le32(priv->cfg_data, value);
break;
}
sync();
return 0;
}
#ifdef CONFIG_FSL_LAW
static int
mpc85xx_pci_dm_setup_laws(struct pci_region *io, struct pci_region *mem,
struct pci_region *pre)
{
/*
* Unfortunately we have defines for this addresse,
* as we have to setup the TLB, and at this stage
* we have no access to DT ... may we check here
* if the value in the define is the same ?
*/
if (mem)
set_next_law(mem->phys_start, law_size_bits(mem->size),
LAW_TRGT_IF_PCI);
if (io)
set_next_law(io->phys_start, law_size_bits(io->size),
LAW_TRGT_IF_PCI);
if (pre)
set_next_law(pre->phys_start, law_size_bits(pre->size),
LAW_TRGT_IF_PCI);
return 0;
}
#endif
static int mpc85xx_pci_dm_probe(struct udevice *dev)
{
struct mpc85xx_pci_priv *priv = dev_get_priv(dev);
struct pci_region *io;
struct pci_region *mem;
struct pci_region *pre;
int count;
ccsr_pcix_t *pcix;
count = pci_get_regions(dev, &io, &mem, &pre);
if (count != 2) {
printf("%s: wrong count of regions %d only 2 allowed\n",
__func__, count);
return -EINVAL;
}
#ifdef CONFIG_FSL_LAW
mpc85xx_pci_dm_setup_laws(io, mem, pre);
#endif
pcix = priv->cfg_addr;
/* BAR 1: memory */
out_be32(&pcix->potar1, mem->bus_start >> 12);
out_be32(&pcix->potear1, (u64)mem->bus_start >> 44);
out_be32(&pcix->powbar1, mem->phys_start >> 12);
out_be32(&pcix->powbear1, (u64)mem->phys_start >> 44);
out_be32(&pcix->powar1, (POWAR_EN | POWAR_MEM_READ |
POWAR_MEM_WRITE | (__ilog2(mem->size) - 1)));
/* BAR 1: IO */
out_be32(&pcix->potar2, io->bus_start >> 12);
out_be32(&pcix->potear2, (u64)io->bus_start >> 44);
out_be32(&pcix->powbar2, io->phys_start >> 12);
out_be32(&pcix->powbear2, (u64)io->phys_start >> 44);
out_be32(&pcix->powar2, (POWAR_EN | POWAR_IO_READ |
POWAR_IO_WRITE | (__ilog2(io->size) - 1)));
out_be32(&pcix->pitar1, 0);
out_be32(&pcix->piwbar1, 0);
out_be32(&pcix->piwar1, (PIWAR_EN | PIWAR_PF | PIWAR_LOCAL |
PIWAR_READ_SNOOP | PIWAR_WRITE_SNOOP | PIWAR_MEM_2G));
out_be32(&pcix->powar3, 0);
out_be32(&pcix->powar4, 0);
out_be32(&pcix->piwar2, 0);
out_be32(&pcix->piwar3, 0);
return 0;
}
static int mpc85xx_pci_dm_remove(struct udevice *dev)
{
return 0;
}
static int mpc85xx_pci_of_to_plat(struct udevice *dev)
{
struct mpc85xx_pci_priv *priv = dev_get_priv(dev);
fdt_addr_t addr;
addr = devfdt_get_addr_index(dev, 0);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
priv->cfg_addr = (void __iomem *)map_physmem(addr, 0, MAP_NOCACHE);
priv->cfg_data = (void __iomem *)((ulong)priv->cfg_addr + 4);
return 0;
}
static const struct dm_pci_ops mpc85xx_pci_ops = {
.read_config = mpc85xx_pci_dm_read_config,
.write_config = mpc85xx_pci_dm_write_config,
};
static const struct udevice_id mpc85xx_pci_ids[] = {
{ .compatible = "fsl,mpc8540-pci" },
{ }
};
U_BOOT_DRIVER(mpc85xx_pci) = {
.name = "mpc85xx_pci",
.id = UCLASS_PCI,
.of_match = mpc85xx_pci_ids,
.ops = &mpc85xx_pci_ops,
.probe = mpc85xx_pci_dm_probe,
.remove = mpc85xx_pci_dm_remove,
.of_to_plat = mpc85xx_pci_of_to_plat,
.priv_auto = sizeof(struct mpc85xx_pci_priv),
};