diff options
Diffstat (limited to 'arch/arm/mach-mvebu/coherency.c')
| -rw-r--r-- | arch/arm/mach-mvebu/coherency.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c index 5723178f6589..a2225070ac3d 100644 --- a/arch/arm/mach-mvebu/coherency.c +++ b/arch/arm/mach-mvebu/coherency.c @@ -32,6 +32,7 @@ #include <linux/pci.h> #include <asm/smp_plat.h> #include <asm/cacheflush.h> +#include <asm/mach/map.h> #include "armada-370-xp.h" #include "coherency.h" #include "mvebu-soc-id.h" @@ -309,9 +310,47 @@ static void __init armada_370_coherency_init(struct device_node *np) set_cpu_coherent(); } +/* + * This ioremap hook is used on Armada 375/38x to ensure that PCIe + * memory areas are mapped as MT_UNCACHED instead of MT_DEVICE. This + * is needed as a workaround for a deadlock issue between the PCIe + * interface and the cache controller. + */ +static void __iomem * +armada_pcie_wa_ioremap_caller(phys_addr_t phys_addr, size_t size, + unsigned int mtype, void *caller) +{ + struct resource pcie_mem; + + mvebu_mbus_get_pcie_mem_aperture(&pcie_mem); + + if (pcie_mem.start <= phys_addr && (phys_addr + size) <= pcie_mem.end) + mtype = MT_UNCACHED; + + return __arm_ioremap_caller(phys_addr, size, mtype, caller); +} + static void __init armada_375_380_coherency_init(struct device_node *np) { + struct device_node *cache_dn; + coherency_cpu_base = of_iomap(np, 0); + arch_ioremap_caller = armada_pcie_wa_ioremap_caller; + + /* + * Add the PL310 property "arm,io-coherent". This makes sure the + * outer sync operation is not used, which allows to + * workaround the system erratum that causes deadlocks when + * doing PCIe in an SMP situation on Armada 375 and Armada + * 38x. + */ + for_each_compatible_node(cache_dn, NULL, "arm,pl310-cache") { + struct property *p; + + p = kzalloc(sizeof(*p), GFP_KERNEL); + p->name = kstrdup("arm,io-coherent", GFP_KERNEL); + of_add_property(cache_dn, p); + } } static int coherency_type(void) |