From: Grant Grundler Date: Wed, 11 Jan 2006 01:47:56 +0000 (-0500) Subject: [PARISC] Truncate overlapping PAT PDC reported ranges X-Git-Tag: v2.6.16-rc1~428^2~11 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6ca45a24ccb847251f71aec8906746d33e99f33e;p=linux-2.6 [PARISC] Truncate overlapping PAT PDC reported ranges Deal with overlapping LBA MMIO resources, rp3440 PDC BUG: PDC reports lmmio range for the last rope that overlaps with the CPU HPA. Console output was: ... Found devices: 1. Storm Peak Fast at 0xfffffffffe798000 [152] { 0, 0x0, 0x889, 0x00004 } 2. Storm Peak Fast at 0xfffffffffe799000 [153] { 0, 0x0, 0x889, 0x00004 } ... FAILED: lba_fixup_bus() request for lmmio_space [fffffffff0000000/fffffffffecffffe] Output is now: LBA: Truncating lmmio_space [fffffffff0000000/fffffffffecffffe] to [fffffffff0000000,fffffffffe797fff] My only concern with this patch is how C8000 (PAT PDC) will report elmmio ranges when a gfx card is installed. I'll have to test this another day. Signed-off-by: Grant Grundler Signed-off-by: James Bottomley Signed-off-by: Matthew Wilcox Signed-off-by: Kyle McMartin --- diff --git a/drivers/parisc/lba_pci.c b/drivers/parisc/lba_pci.c index 4f6bdf0881..cbae8c8963 100644 --- a/drivers/parisc/lba_pci.c +++ b/drivers/parisc/lba_pci.c @@ -695,11 +695,71 @@ lba_claim_dev_resources(struct pci_dev *dev) } } } + + +/* + * truncate_pat_collision: Deal with overlaps or outright collisions + * between PAT PDC reported ranges. + * + * Broken PA8800 firmware will report lmmio range that + * overlaps with CPU HPA. Just truncate the lmmio range. + * + * BEWARE: conflicts with this lmmio range may be an + * elmmio range which is pointing down another rope. + * + * FIXME: only deals with one collision per range...theoretically we + * could have several. Supporting more than one collision will get messy. + */ +static unsigned long +truncate_pat_collision(struct resource *root, struct resource *new) +{ + unsigned long start = new->start; + unsigned long end = new->end; + struct resource *tmp = root->child; + + if (end <= start || start < root->start || !tmp) + return 0; + + /* find first overlap */ + while (tmp && tmp->end < start) + tmp = tmp->sibling; + + /* no entries overlap */ + if (!tmp) return 0; + + /* found one that starts behind the new one + ** Don't need to do anything. + */ + if (tmp->start >= end) return 0; + + if (tmp->start <= start) { + /* "front" of new one overlaps */ + new->start = tmp->end + 1; + + if (tmp->end >= end) { + /* AACCKK! totally overlaps! drop this range. */ + return 1; + } + } + + if (tmp->end < end ) { + /* "end" of new one overlaps */ + new->end = tmp->start - 1; + } + + printk(KERN_WARNING "LBA: Truncating lmmio_space [%lx/%lx] " + "to [%lx,%lx]\n", + start, end, + new->start, new->end ); + + return 0; /* truncation successful */ +} + #else -#define lba_claim_dev_resources(dev) +#define lba_claim_dev_resources(dev) do { } while (0) +#define truncate_pat_collision(r,n) (0) #endif - /* ** The algorithm is generic code. ** But it needs to access local data structures to get the IRQ base. @@ -747,6 +807,9 @@ lba_fixup_bus(struct pci_bus *bus) lba_dump_res(&ioport_resource, 2); BUG(); } + /* advertize Host bridge resources to PCI bus */ + bus->resource[0] = &(ldev->hba.io_space); + i = 1; if (ldev->hba.elmmio_space.start) { err = request_resource(&iomem_resource, @@ -760,23 +823,35 @@ lba_fixup_bus(struct pci_bus *bus) /* lba_dump_res(&iomem_resource, 2); */ /* BUG(); */ - } + } else + bus->resource[i++] = &(ldev->hba.elmmio_space); } - err = request_resource(&iomem_resource, &(ldev->hba.lmmio_space)); - if (err < 0) { - /* FIXME overlaps with elmmio will fail here. - * Need to prune (or disable) the distributed range. - * - * BEWARE: conflicts with this lmmio range may be - * elmmio range which is pointing down another rope. - */ - - printk("FAILED: lba_fixup_bus() request for " + + /* Overlaps with elmmio can (and should) fail here. + * We will prune (or ignore) the distributed range. + * + * FIXME: SBA code should register all elmmio ranges first. + * that would take care of elmmio ranges routed + * to a different rope (already discovered) from + * getting registered *after* LBA code has already + * registered it's distributed lmmio range. + */ + if (truncate_pat_collision(&iomem_resource, + &(ldev->hba.lmmio_space))) { + + printk(KERN_WARNING "LBA: lmmio_space [%lx/%lx] duplicate!\n", + ldev->hba.lmmio_space.start, + ldev->hba.lmmio_space.end); + } else { + err = request_resource(&iomem_resource, &(ldev->hba.lmmio_space)); + if (err < 0) { + printk(KERN_ERR "FAILED: lba_fixup_bus() request for " "lmmio_space [%lx/%lx]\n", ldev->hba.lmmio_space.start, ldev->hba.lmmio_space.end); - /* lba_dump_res(&iomem_resource, 2); */ + } else + bus->resource[i++] = &(ldev->hba.lmmio_space); } #ifdef CONFIG_64BIT @@ -791,18 +866,10 @@ lba_fixup_bus(struct pci_bus *bus) lba_dump_res(&iomem_resource, 2); BUG(); } + bus->resource[i++] = &(ldev->hba.gmmio_space); } #endif - /* advertize Host bridge resources to PCI bus */ - bus->resource[0] = &(ldev->hba.io_space); - bus->resource[1] = &(ldev->hba.lmmio_space); - i=2; - if (ldev->hba.elmmio_space.start) - bus->resource[i++] = &(ldev->hba.elmmio_space); - if (ldev->hba.gmmio_space.start) - bus->resource[i++] = &(ldev->hba.gmmio_space); - } list_for_each(ln, &bus->devices) {