powerpc/pasemi: Add PCI initialisation for Nemo board.

The A-Eon Amigaone X1000's Nemo motherboard has an AMD SB600
connected to one of the PCI-e root ports on its PaSemi
Pwrficient 1628M SoC. Normally the SB600 southbridge would be
connected to a hidden PCI-e port on the system's northbridge,
and as a result doesn't fully comply with the PCI-e spec.

Add code to relax the PCI-e detection in both the root port
and the Linux kernel allowing on board devices to be detected.

Signed-off-by: Darren Stevens <darren@stevens-zone.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Darren Stevens 2018-08-19 21:21:55 +01:00 committed by Michael Ellerman
parent 49a502ea23
commit 68f211a4d1

View file

@ -108,6 +108,61 @@ static int workaround_5945(struct pci_bus *bus, unsigned int devfn,
return 1;
}
#ifdef CONFIG_PPC_PASEMI_NEMO
#define PXP_ERR_CFG_REG 0x4
#define PXP_IGNORE_PCIE_ERRORS 0x800
#define SB600_BUS 5
static void sb600_set_flag(int bus)
{
static void __iomem *iob_mapbase = NULL;
struct resource res;
struct device_node *dn;
int err;
if (iob_mapbase == NULL) {
dn = of_find_compatible_node(NULL, "isa", "pasemi,1682m-iob");
if (!dn) {
pr_crit("NEMO SB600 missing iob node\n");
return;
}
err = of_address_to_resource(dn, 0, &res);
of_node_put(dn);
if (err) {
pr_crit("NEMO SB600 missing resource\n");
return;
}
pr_info("NEMO SB600 IOB base %08llx\n",res.start);
iob_mapbase = ioremap(res.start + 0x100, 0x94);
}
if (iob_mapbase != NULL) {
if (bus == SB600_BUS) {
/*
* This is the SB600's bus, tell the PCI-e root port
* to allow non-zero devices to enumerate.
*/
out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) | PXP_IGNORE_PCIE_ERRORS);
} else {
/*
* Only scan device 0 on other busses
*/
out_le32(iob_mapbase + PXP_ERR_CFG_REG, in_le32(iob_mapbase + PXP_ERR_CFG_REG) & ~PXP_IGNORE_PCIE_ERRORS);
}
}
}
#else
static void sb600_set_flag(int bus)
{
}
#endif
static int pa_pxp_read_config(struct pci_bus *bus, unsigned int devfn,
int offset, int len, u32 *val)
{