diff options
| author | Scott Wood <scottwood@freescale.com> | 2014-08-09 03:40:45 +0400 |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2014-09-04 02:58:22 +0400 |
| commit | 84f44cc56c0994df7778bde55c8d5e9aa9fff8f5 (patch) | |
| tree | c757d5564181fc2092e59fbb025cfb93eb86393d /arch/powerpc/platforms/85xx/qemu_e500.c | |
| parent | cf5621032fbe7354c0c3fff17958b7029bbc9f30 (diff) | |
| download | linux-84f44cc56c0994df7778bde55c8d5e9aa9fff8f5.tar.xz | |
powerpc/fsl-pci: Limit ZONE_DMA32 to 2GiB on 64-bit platforms
FSL PCI cannot directly address the whole lower 4 GiB due to
conflicts with PCICSRBAR and outbound windows. By the time
max_direct_dma_addr is set to the precise limit, it will be too late to
alter the zone limits, but we should always have at least 2 GiB mapped
(unless RAM is smaller than that).
Signed-off-by: Scott Wood <scottwood@freescale.com>
Cc: Shaohui Xie <Shaohui.Xie@freescale.com>
Diffstat (limited to 'arch/powerpc/platforms/85xx/qemu_e500.c')
| -rw-r--r-- | arch/powerpc/platforms/85xx/qemu_e500.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/85xx/qemu_e500.c b/arch/powerpc/platforms/85xx/qemu_e500.c index 7f2673293549..8ad2fe6f200a 100644 --- a/arch/powerpc/platforms/85xx/qemu_e500.c +++ b/arch/powerpc/platforms/85xx/qemu_e500.c @@ -18,6 +18,7 @@ #include <linux/kernel.h> #include <linux/of_fdt.h> #include <asm/machdep.h> +#include <asm/pgtable.h> #include <asm/time.h> #include <asm/udbg.h> #include <asm/mpic.h> @@ -44,6 +45,15 @@ static void __init qemu_e500_setup_arch(void) fsl_pci_assign_primary(); swiotlb_detect_4g(); +#if defined(CONFIG_FSL_PCI) && defined(CONFIG_ZONE_DMA32) + /* + * Inbound windows don't cover the full lower 4 GiB + * due to conflicts with PCICSRBAR and outbound windows, + * so limit the DMA32 zone to 2 GiB, to allow consistent + * allocations to succeed. + */ + limit_zone_pfn(ZONE_DMA32, 1UL << (31 - PAGE_SHIFT)); +#endif mpc85xx_smp_init(); } |