MIPS: Add NUMA support for Loongson-3

Multiple Loongson-3A chips can be interconnected with HT0-bus. This is
a CC-NUMA system that every chip (node) has its own local memory and
cache coherency is maintained by hardware. The 64-bit physical memory
address format is as follows:

0x-0000-YZZZ-ZZZZ-ZZZZ

The high 16 bits should be 0, which means the real physical address
supported by Loongson-3 is 48-bit. The "Y" bits is the base address of
each node, which can be also considered as the node-id. The "Z" bits is
the address offset within a node, which means every node has a 44 bits
address space.

Macros XPHYSADDR and MAX_PHYSMEM_BITS are modified unconditionally,
because many other MIPS CPUs have also extended their address spaces.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/7187/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

3 files changed, 299 insertions, 2 deletions

diff --git a/arch/mips/loongson/loongson-3/Makefile b/arch/mips/loongson/loongson-3/Makefile
index 70152b252ddc..471b0f2af079 100644
--- a/arch/mips/loongson/loongson-3/Makefile
+++ b/arch/mips/loongson/loongson-3/Makefile
@@ -4,3 +4,5 @@
 obj-y			+= irq.o
 
 obj-$(CONFIG_SMP)	+= smp.o
+
+obj-$(CONFIG_NUMA)	+= numa.o
diff --git a/arch/mips/loongson/loongson-3/numa.c b/arch/mips/loongson/loongson-3/numa.c
new file mode 100644
index 000000000000..ca025a6ba559
--- /dev/null
+++ b/arch/mips/loongson/loongson-3/numa.c
@@ -0,0 +1,291 @@
+/*
+ * Copyright (C) 2010 Loongson Inc. & Lemote Inc. &
+ *                    Insititute of Computing Technology
+ * Author:  Xiang Gao, gaoxiang@ict.ac.cn
+ *          Huacai Chen, chenhc@lemote.com
+ *          Xiaofu Meng, Shuangshuang Zhang
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+#include <linux/nodemask.h>
+#include <linux/swap.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
+#include <linux/pfn.h>
+#include <linux/highmem.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <linux/bootmem.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <asm/bootinfo.h>
+#include <asm/mc146818-time.h>
+#include <asm/time.h>
+#include <asm/wbflush.h>
+#include <boot_param.h>
+
+static struct node_data prealloc__node_data[MAX_NUMNODES];
+unsigned char __node_distances[MAX_NUMNODES][MAX_NUMNODES];
+struct node_data *__node_data[MAX_NUMNODES];
+EXPORT_SYMBOL(__node_data);
+
+static void enable_lpa(void)
+{
+	unsigned long value;
+
+	value = __read_32bit_c0_register($16, 3);
+	value |= 0x00000080;
+	__write_32bit_c0_register($16, 3, value);
+	value = __read_32bit_c0_register($16, 3);
+	pr_info("CP0_Config3: CP0 16.3 (0x%lx)\n", value);
+
+	value = __read_32bit_c0_register($5, 1);
+	value |= 0x20000000;
+	__write_32bit_c0_register($5, 1, value);
+	value = __read_32bit_c0_register($5, 1);
+	pr_info("CP0_PageGrain: CP0 5.1 (0x%lx)\n", value);
+}
+
+static void cpu_node_probe(void)
+{
+	int i;
+
+	nodes_clear(node_possible_map);
+	nodes_clear(node_online_map);
+	for (i = 0; i < loongson_sysconf.nr_nodes; i++) {
+		node_set_state(num_online_nodes(), N_POSSIBLE);
+		node_set_online(num_online_nodes());
+	}
+
+	pr_info("NUMA: Discovered %d cpus on %d nodes\n",
+		loongson_sysconf.nr_cpus, num_online_nodes());
+}
+
+static int __init compute_node_distance(int row, int col)
+{
+	int package_row = row * loongson_sysconf.cores_per_node /
+				loongson_sysconf.cores_per_package;
+	int package_col = col * loongson_sysconf.cores_per_node /
+				loongson_sysconf.cores_per_package;
+
+	if (col == row)
+		return 0;
+	else if (package_row == package_col)
+		return 40;
+	else
+		return 100;
+}
+
+static void __init init_topology_matrix(void)
+{
+	int row, col;
+
+	for (row = 0; row < MAX_NUMNODES; row++)
+		for (col = 0; col < MAX_NUMNODES; col++)
+			__node_distances[row][col] = -1;
+
+	for_each_online_node(row) {
+		for_each_online_node(col) {
+			__node_distances[row][col] =
+				compute_node_distance(row, col);
+		}
+	}
+}
+
+static unsigned long nid_to_addroffset(unsigned int nid)
+{
+	unsigned long result;
+	switch (nid) {
+	case 0:
+	default:
+		result = NODE0_ADDRSPACE_OFFSET;
+		break;
+	case 1:
+		result = NODE1_ADDRSPACE_OFFSET;
+		break;
+	case 2:
+		result = NODE2_ADDRSPACE_OFFSET;
+		break;
+	case 3:
+		result = NODE3_ADDRSPACE_OFFSET;
+		break;
+	}
+	return result;
+}
+
+static void __init szmem(unsigned int node)
+{
+	u32 i, mem_type;
+	static unsigned long num_physpages = 0;
+	u64 node_id, node_psize, start_pfn, end_pfn, mem_start, mem_size;
+
+	/* Parse memory information and activate */
+	for (i = 0; i < loongson_memmap->nr_map; i++) {
+		node_id = loongson_memmap->map[i].node_id;
+		if (node_id != node)
+			continue;
+
+		mem_type = loongson_memmap->map[i].mem_type;
+		mem_size = loongson_memmap->map[i].mem_size;
+		mem_start = loongson_memmap->map[i].mem_start;
+
+		switch (mem_type) {
+		case SYSTEM_RAM_LOW:
+			start_pfn = ((node_id << 44) + mem_start) >> PAGE_SHIFT;
+			node_psize = (mem_size << 20) >> PAGE_SHIFT;
+			end_pfn  = start_pfn + node_psize;
+			num_physpages += node_psize;
+			pr_info("Node%d: mem_type:%d, mem_start:0x%llx, mem_size:0x%llx MB\n",
+				(u32)node_id, mem_type, mem_start, mem_size);
+			pr_info("       start_pfn:0x%llx, end_pfn:0x%llx, num_physpages:0x%lx\n",
+				start_pfn, end_pfn, num_physpages);
+			add_memory_region((node_id << 44) + mem_start,
+				(u64)mem_size << 20, BOOT_MEM_RAM);
+			memblock_add_node(PFN_PHYS(start_pfn),
+				PFN_PHYS(end_pfn - start_pfn), node);
+			break;
+		case SYSTEM_RAM_HIGH:
+			start_pfn = ((node_id << 44) + mem_start) >> PAGE_SHIFT;
+			node_psize = (mem_size << 20) >> PAGE_SHIFT;
+			end_pfn  = start_pfn + node_psize;
+			num_physpages += node_psize;
+			pr_info("Node%d: mem_type:%d, mem_start:0x%llx, mem_size:0x%llx MB\n",
+				(u32)node_id, mem_type, mem_start, mem_size);
+			pr_info("       start_pfn:0x%llx, end_pfn:0x%llx, num_physpages:0x%lx\n",
+				start_pfn, end_pfn, num_physpages);
+			add_memory_region((node_id << 44) + mem_start,
+				(u64)mem_size << 20, BOOT_MEM_RAM);
+			memblock_add_node(PFN_PHYS(start_pfn),
+				PFN_PHYS(end_pfn - start_pfn), node);
+			break;
+		case MEM_RESERVED:
+			pr_info("Node%d: mem_type:%d, mem_start:0x%llx, mem_size:0x%llx MB\n",
+				(u32)node_id, mem_type, mem_start, mem_size);
+			add_memory_region((node_id << 44) + mem_start,
+				(u64)mem_size << 20, BOOT_MEM_RESERVED);
+			memblock_reserve(((node_id << 44) + mem_start),
+				mem_size << 20);
+			break;
+		}
+	}
+}
+
+static void __init node_mem_init(unsigned int node)
+{
+	unsigned long bootmap_size;
+	unsigned long node_addrspace_offset;
+	unsigned long start_pfn, end_pfn, freepfn;
+
+	node_addrspace_offset = nid_to_addroffset(node);
+	pr_info("Node%d's addrspace_offset is 0x%lx\n",
+			node, node_addrspace_offset);
+
+	get_pfn_range_for_nid(node, &start_pfn, &end_pfn);
+	freepfn = start_pfn;
+	if (node == 0)
+		freepfn = PFN_UP(__pa_symbol(&_end)); /* kernel end address */
+	pr_info("Node%d: start_pfn=0x%lx, end_pfn=0x%lx, freepfn=0x%lx\n",
+		node, start_pfn, end_pfn, freepfn);
+
+	__node_data[node] = prealloc__node_data + node;
+
+	NODE_DATA(node)->bdata = &bootmem_node_data[node];
+	NODE_DATA(node)->node_start_pfn = start_pfn;
+	NODE_DATA(node)->node_spanned_pages = end_pfn - start_pfn;
+
+	bootmap_size = init_bootmem_node(NODE_DATA(node), freepfn,
+					start_pfn, end_pfn);
+	free_bootmem_with_active_regions(node, end_pfn);
+	if (node == 0) /* used by finalize_initrd() */
+		max_low_pfn = end_pfn;
+
+	/* This is reserved for the kernel and bdata->node_bootmem_map */
+	reserve_bootmem_node(NODE_DATA(node), start_pfn << PAGE_SHIFT,
+		((freepfn - start_pfn) << PAGE_SHIFT) + bootmap_size,
+		BOOTMEM_DEFAULT);
+
+	if (node == 0 && node_end_pfn(0) >= (0xffffffff >> PAGE_SHIFT)) {
+		/* Reserve 0xff800000~0xffffffff for RS780E integrated GPU */
+		reserve_bootmem_node(NODE_DATA(node),
+				(node_addrspace_offset | 0xff800000),
+				8 << 20, BOOTMEM_DEFAULT);
+	}
+
+	sparse_memory_present_with_active_regions(node);
+}
+
+static __init void prom_meminit(void)
+{
+	unsigned int node, cpu;
+
+	cpu_node_probe();
+	init_topology_matrix();
+
+	for (node = 0; node < loongson_sysconf.nr_nodes; node++) {
+		if (node_online(node)) {
+			szmem(node);
+			node_mem_init(node);
+			cpus_clear(__node_data[(node)]->cpumask);
+		}
+	}
+	for (cpu = 0; cpu < loongson_sysconf.nr_cpus; cpu++) {
+		node = cpu / loongson_sysconf.cores_per_node;
+		if (node >= num_online_nodes())
+			node = 0;
+		pr_info("NUMA: set cpumask cpu %d on node %d\n", cpu, node);
+		cpu_set(cpu, __node_data[(node)]->cpumask);
+	}
+}
+
+void __init paging_init(void)
+{
+	unsigned node;
+	unsigned long zones_size[MAX_NR_ZONES] = {0, };
+
+	pagetable_init();
+
+	for_each_online_node(node) {
+		unsigned long  start_pfn, end_pfn;
+
+		get_pfn_range_for_nid(node, &start_pfn, &end_pfn);
+
+		if (end_pfn > max_low_pfn)
+			max_low_pfn = end_pfn;
+	}
+#ifdef CONFIG_ZONE_DMA32
+	zones_size[ZONE_DMA32] = MAX_DMA32_PFN;
+#endif
+	zones_size[ZONE_NORMAL] = max_low_pfn;
+	free_area_init_nodes(zones_size);
+}
+
+void __init mem_init(void)
+{
+	high_memory = (void *) __va(get_num_physpages() << PAGE_SHIFT);
+	free_all_bootmem();
+	setup_zero_pages();	/* This comes from node 0 */
+	mem_init_print_info(NULL);
+}
+
+/* All PCI device belongs to logical Node-0 */
+int pcibus_to_node(struct pci_bus *bus)
+{
+	return 0;
+}
+EXPORT_SYMBOL(pcibus_to_node);
+
+void __init prom_init_numa_memory(void)
+{
+	enable_lpa();
+	prom_meminit();
+}
+EXPORT_SYMBOL(prom_init_numa_memory);
diff --git a/arch/mips/loongson/loongson-3/smp.c b/arch/mips/loongson/loongson-3/smp.c
index 3c320e709e91..ed0e2d0f87ab 100644
--- a/arch/mips/loongson/loongson-3/smp.c
+++ b/arch/mips/loongson/loongson-3/smp.c
@@ -203,6 +203,8 @@ static void loongson3_init_secondary(void)
 	for (i = 0; i < loongson_sysconf.nr_cpus; i++)
 		loongson3_ipi_write32(0xffffffff, ipi_en0_regs[i]);
 
+	cpu_data[cpu].package = cpu / loongson_sysconf.cores_per_package;
+	cpu_data[cpu].core = cpu % loongson_sysconf.cores_per_package;
 	per_cpu(cpu_state, cpu) = CPU_ONLINE;
 
 	i = 0;
@@ -394,17 +396,19 @@ static int loongson3_cpu_callback(struct notifier_block *nfb,
 	unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (unsigned long)hcpu;
+	uint64_t core_id = cpu_data[cpu].core;
+	uint64_t package_id = cpu_data[cpu].package;
 
 	switch (action) {
 	case CPU_POST_DEAD:
 	case CPU_POST_DEAD_FROZEN:
 		pr_info("Disable clock for CPU#%d\n", cpu);
-		LOONGSON_CHIPCFG(0) &= ~(1 << (12 + cpu));
+		LOONGSON_CHIPCFG(package_id) &= ~(1 << (12 + core_id));
 		break;
 	case CPU_UP_PREPARE:
 	case CPU_UP_PREPARE_FROZEN:
 		pr_info("Enable clock for CPU#%d\n", cpu);
-		LOONGSON_CHIPCFG(0) |= 1 << (12 + cpu);
+		LOONGSON_CHIPCFG(package_id) |= 1 << (12 + core_id);
 		break;
 	}