ramips: mt7621: setup memory region for pcie controller memory

Only compile tested since I do not have any hardware with
devices on pcie bus.

Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>

SVN-Revision: 47904

target/linux/ramips/patches-4.3/0061-mt7621-set-up-pci-memory-region.patch

@@ -0,0 +1,42 @@
+--- a/arch/mips/pci/pci-mt7621.c
++++ b/arch/mips/pci/pci-mt7621.c
+@@ -46,6 +46,7 @@
+ #include <linux/version.h>
+ #include <asm/pci.h>
+ #include <asm/io.h>
++#include <asm/mips-cm.h>
+ #include <linux/init.h>
+ #include <linux/module.h>
+ #include <linux/delay.h>
+@@ -553,6 +554,23 @@ set_phy_for_ssc(void)
+ #endif
+ }
+ 
++void setup_cm_memory_region(struct resource *mem_resource)
++{
++	resource_size_t mask;
++	if (mips_cm_numiocu()) {
++		/* FIXME: hardware doesn't accept mask values with 1s after
++		   0s (e.g. 0xffef), so it would be great to warn if that's
++		   about to happen */
++		mask = ~(mem_resource->end - mem_resource->start);
++
++		write_gcr_reg1_base(mem_resource->start);
++		write_gcr_reg1_mask(mask | CM_GCR_REGn_MASK_CMTGT_IOCU0);
++		printk("PCI coherence region base: 0x%08lx, mask/settings: 0x%08lx\n",
++		       read_gcr_reg1_base(),
++		       read_gcr_reg1_mask());
++	}
++}
++
+ static int mt7621_pci_probe(struct platform_device *pdev)
+ {
+ 	unsigned long val = 0;
+@@ -780,6 +798,7 @@ pcie(2/1/0) link status	pcie2_num	pcie1_
+ 	}
+ 
+ 	pci_load_of_ranges(&mt7621_controller, pdev->dev.of_node);
++	setup_cm_memory_region(mt7621_controller.mem_resource);
+ 	register_pci_controller(&mt7621_controller);
+ 	return 0;
+