@@ -22,15 +22,65 @@
*/
#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
+#include <linux/slab.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include "core.h"
+#define VERSATILE_SYS_PCICTL_OFFSET 0x44
+static void __iomem *versatile_sys_base;
+
+static void __init versatile_dt_pci_init(void)
+{
+ u32 val;
+ struct device_node *np;
+ struct property *newprop;
+
+ np = of_find_compatible_node(NULL, NULL, "arm,versatile-pci");
+ if (!np)
+ return;
+
+ /* Check if PCI backplane is detected */
+ val = readl(versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
+ if (val & 1) {
+ /*
+ * Enable PCI accesses. Note that the documentaton is
+ * inconsistent whether or not this is needed, but the old
+ * driver had it so we will keep it.
+ */
+ writel(1, versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
+ return;
+ }
+
+ newprop = kzalloc(sizeof(*newprop), GFP_KERNEL);
+ if (!newprop)
+ return;
+
+ newprop->name = kstrdup("status", GFP_KERNEL);
+ newprop->value = kstrdup("disabled", GFP_KERNEL);
+ newprop->length = sizeof("disabled");
+ of_update_property(np, newprop);
+
+ pr_info("Not plugged into PCI backplane!\n");
+}
+
static void __init versatile_dt_init(void)
{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "arm,core-module-versatile");
+ if (np)
+ versatile_sys_base = of_iomap(np, 0);
+ WARN_ON(!versatile_sys_base);
+
+ versatile_dt_pci_init();
+
of_platform_populate(NULL, of_default_bus_match_table,
versatile_auxdata_lookup, NULL);
}
Disable the Versatile PCI DT node when no PCI backplane is detected. This will prevent the Versatile PCI driver from probing when PCI is not populated. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> --- arch/arm/mach-versatile/versatile_dt.c | 50 ++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+)