dm: pci: Allow delaying auto-config until after relocation

At present PCI auto-configuration happens in U-Boot both before and after
relocation. This is a waste of time and may mess up static addresses used
in board_init_f(). Adjust the code to supporting doing auto-configuration
once, after relocation, under control of a device-tree property.

This is needed for Apollo Lake for debugging the silicon-init code. Once
the UART is moved to a different MMIO address the debug UART does not work
and any debug output in Apollo Lake's arch_fsp_init_r() causes a hang.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
This commit is contained in:
Simon Glass 2019-12-06 21:41:37 -07:00 committed by Bin Meng
parent b14c533986
commit 2206ac248a
3 changed files with 42 additions and 6 deletions

View File

@ -0,0 +1,24 @@
x86 PCI DT details:
===================
Some options are available to affect how PCI operates on x86.
Optional properties:
- u-boot,skip-auto-config-until-reloc : Don't set up PCI configuration until
after U-Boot has relocated. Normally if PCI is used before relocation,
this happens before relocation also. Some platforms set up static
configuration in TPL/SPL to reduce code size and boot time, since these
phases only know about a small subset of PCI devices.
Example:
pci {
compatible = "pci-x86";
#address-cells = <3>;
#size-cells = <2>;
u-boot,dm-pre-reloc;
ranges = <0x02000000 0x0 0xc0000000 0xc0000000 0 0x10000000
0x42000000 0x0 0xb0000000 0xb0000000 0 0x10000000
0x01000000 0x0 0x1000 0x1000 0 0xefff>;
u-boot,skip-auto-config-until-reloc;
};

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@ -975,12 +975,15 @@ static int pci_uclass_pre_probe(struct udevice *bus)
hose->bus = bus;
hose->first_busno = bus->seq;
hose->last_busno = bus->seq;
hose->skip_auto_config_until_reloc =
dev_read_bool(bus, "u-boot,skip-auto-config-until-reloc");
return 0;
}
static int pci_uclass_post_probe(struct udevice *bus)
{
struct pci_controller *hose = dev_get_uclass_priv(bus);
int ret;
debug("%s: probing bus %d\n", __func__, bus->seq);
@ -988,11 +991,13 @@ static int pci_uclass_post_probe(struct udevice *bus)
if (ret)
return ret;
#if CONFIG_IS_ENABLED(PCI_PNP)
ret = pci_auto_config_devices(bus);
if (ret < 0)
return ret;
#endif
if (CONFIG_IS_ENABLED(PCI_PNP) &&
(!hose->skip_auto_config_until_reloc ||
(gd->flags & GD_FLG_RELOC))) {
ret = pci_auto_config_devices(bus);
if (ret < 0)
return log_msg_ret("pci auto-config", ret);
}
#if defined(CONFIG_X86) && defined(CONFIG_HAVE_FSP)
/*

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@ -571,15 +571,22 @@ extern void pci_cfgfunc_config_device(struct pci_controller* hose, pci_dev_t dev
#define INDIRECT_TYPE_NO_PCIE_LINK 1
/*
/**
* Structure of a PCI controller (host bridge)
*
* With driver model this is dev_get_uclass_priv(bus)
*
* @skip_auto_config_until_reloc: true to avoid auto-config until U-Boot has
* relocated. Normally if PCI is used before relocation, this happens
* before relocation also. Some platforms set up static configuration in
* TPL/SPL to reduce code size and boot time, since these phases only know
* about a small subset of PCI devices. This is normally false.
*/
struct pci_controller {
#ifdef CONFIG_DM_PCI
struct udevice *bus;
struct udevice *ctlr;
bool skip_auto_config_until_reloc;
#else
struct pci_controller *next;
#endif