Hi Darren,
Thanks for the patch, sorry it's taken so long to get merged.
Darren Stevens <dar...@stevens-zone.net> writes:
> 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 <dar...@stevens-zone.net>
This should not be indented.
> diff --git a/arch/powerpc/platforms/pasemi/pasemi.h
> b/arch/powerpc/platforms/pasemi/pasemi.h
> index 329d2a6..8900dee 100644
> --- a/arch/powerpc/platforms/pasemi/pasemi.h
> +++ b/arch/powerpc/platforms/pasemi/pasemi.h
> @@ -3,6 +3,9 @@
> #define _PASEMI_PASEMI_H
>
> extern unsigned long pas_get_boot_time(void);
> +#ifdef CONFIG_PPC_PASEMI_NEMO
> +extern void nemo_pci_init(void);
> +#endif
We don't need an #ifdef around this thanks.
> diff --git a/arch/powerpc/platforms/pasemi/pci.c
> b/arch/powerpc/platforms/pasemi/pci.c
> index 5ff6108..cb0ac87 100644
> --- a/arch/powerpc/platforms/pasemi/pci.c
> +++ b/arch/powerpc/platforms/pasemi/pci.c
> @@ -108,6 +109,92 @@ static int workaround_5945(struct pci_bus *bus, unsigned
> int devfn,
> return 1;
> }
>
> +#ifdef CONFIG_PPC_PASEMI_NEMO
> +static int sb600_bus = 5;
That's only used once so could just be a #define, or even a literal in
the code.
> +static void __iomem *iob_mapbase = NULL;
That's only used in sb6000_set_flag() so should be in there shouldn't it?
> +static void sb600_set_flag(int bus)
> +{
> + 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) {
> + printk(KERN_CRIT "NEMO SB600 missing iob node\n");
I'm not sure CRIT is really necessary, we tend to use ERR, but I don't
mind that much.
But can you use pr_err()/pr_crit() please.
> + return;
> + }
> +
> + err = of_address_to_resource(dn, 0, &res);
> + of_node_put(dn);
> +
> + if (err) {
> + printk(KERN_CRIT "NEMO SB600 missing resource\n");
> + return;
> + }
> +
> + printk(KERN_CRIT "NEMO SB600 IOB base %08lx\n",res.start);
That's INFO or even DEBUG.
> +
> + iob_mapbase = ioremap(res.start + 0x100, 0x94);
0x94 ?
It's going to map you at least one page anyway.
> + }
> +
> + 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 + 4, in_le32(iob_mapbase + 4) |
> 0x800);
Does reg #4 have a name?
Or 0x800 ?
> + } else {
> + /*
> + * Only scan device 0 on other busses
> + */
> + out_le32(iob_mapbase + 4, in_le32(iob_mapbase + 4) &
> ~0x800);
> + }
> + }
> +}
> +
> +static int nemo_pxp_read_config(struct pci_bus *bus, unsigned int devfn,
> + int offset, int len, u32 *val)
> +{
> + struct pci_controller *hose;
Can we call them host or controller or something in new code?
> + void volatile __iomem *addr;
Does that need to be volatile?
> + hose = pci_bus_to_host(bus);
> + if (!hose)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + if (!pa_pxp_offset_valid(bus->number, devfn, offset))
> + return PCIBIOS_BAD_REGISTER_NUMBER;
> +
> + if (workaround_5945(bus, devfn, offset, len, val))
> + return PCIBIOS_SUCCESSFUL;
> +
> + addr = pa_pxp_cfg_addr(hose, bus->number, devfn, offset);
> +
> + sb600_set_flag(bus->number);
> +
> + /*
> + * Note: the caller has already checked that offset is
> + * suitably aligned and that len is 1, 2 or 4.
> + */
> + switch (len) {
> + case 1:
> + *val = in_8(addr);
> + break;
> + case 2:
> + *val = in_le16(addr);
> + break;
> + default:
> + *val = in_le32(addr);
> + break;
> + }
> +
> + return PCIBIOS_SUCCESSFUL;
> +}
> +#endif
> +
> static int pa_pxp_read_config(struct pci_bus *bus, unsigned int devfn,
> int offset, int len, u32 *val)
> {
> @@ -178,6 +265,20 @@ static int pa_pxp_write_config(struct pci_bus *bus,
> unsigned int devfn,
> return PCIBIOS_SUCCESSFUL;
> }
>
> +#ifdef CONFIG_PPC_PASEMI_NEMO
> +static struct pci_ops nemo_pxp_ops = {
> + .read = nemo_pxp_read_config,
> + .write = pa_pxp_write_config,
> +};
> +
> +static void __init setup_nemo_pxp(struct pci_controller *hose)
> +{
> + hose->ops = &nemo_pxp_ops;
> + hose->cfg_data = ioremap(0xe0000000, 0x10000000);
> +}
Could these go in one of the ifdef block below? Just to reduce the
number of times we ifdef NEMO.
> @@ -213,6 +343,28 @@ static int __init pas_add_bridge(struct device_node *dev)
> return 0;
> }
>
> +#ifdef CONFIG_PPC_PASEMI_NEMO
> +void __init nemo_pci_init(void)
> +{
> + struct device_node *np, *root;
> +
> + root = of_find_node_by_path("/");
> + if (!root) {
> + printk(KERN_CRIT "pas_pci_init: can't find root "
> + "of device tree\n");
TBH that can't really happen, or if it does we're not going to boot
elsewhere.
So the printk() is probably overkill.
> + return;
> + }
> +
> + pci_set_flags(PCI_SCAN_ALL_PCIE_DEVS);
> +
> + for (np = NULL; (np = of_get_next_child(root, np)) != NULL;)
Does the pxp node not have a compatible property? (I may have asked that
before).
Normally you'd search by compatible, not name.
If you have to search by name then of_get_child_by_name() should work.
> + if (np->name && !strcmp(np->name, "pxp") &&
> !nemo_add_bridge(np))
> + of_node_get(np);
Why are we of_node_get()'ing here?
If nemo_add_bridge() wants to keep a reference it should do that itself.
> +
> + of_node_put(root);
> +}
> +#endif
> +
> void __init pas_pci_init(void)
> {
> struct device_node *np, *root;
cheers
