[PATCH V2 0/2] LoongArch: Support booting with FDT

[PATCH V2 0/2] LoongArch: Support booting with FDT

[Binbin Zhou]

Hi all:

Since LoongArch will soon support FDT booting, such as the Loongson-2K
series, this patchset adds relevant booting support and parameter
parsing.

Changes in V2:
 patch(1/2)
   - Update comments and commit messages (setup.c);
   - Give the general method to get the FDT Pointer from EFI (efi.c);
   - Add SMP support based on FDT (smp.c);
   - Call early_init_dt_scan_chosen_stdout() only when
     earlycon_acpi_spcr_enable is true (kernel/acpi.c);
   - Fix illegal access during pci root bridge registration (pci/acpi.c).
 patch(2/2)
   - Newly added.

Thanks.

Binbin Zhou (2):
  LoongArch: Support booting with FDT from efi system table
  LoongArch: Process ISA Node in DeviceTree

 arch/loongarch/Kconfig             |   2 +
 arch/loongarch/include/asm/efi.h   |   1 +
 arch/loongarch/include/asm/setup.h |   1 +
 arch/loongarch/kernel/acpi.c       |  11 ++-
 arch/loongarch/kernel/efi.c        |  19 +++-
 arch/loongarch/kernel/env.c        |   3 +
 arch/loongarch/kernel/reset.c      |   3 +-
 arch/loongarch/kernel/setup.c      | 137 ++++++++++++++++++++++++++++-
 arch/loongarch/kernel/smp.c        |  32 +++++++
 arch/loongarch/pci/acpi.c          |   5 +-
 10 files changed, 207 insertions(+), 7 deletions(-)

-- 
2.31.1

[PATCH V2 1/2] LoongArch: Support booting with FDT from efi system table

[Binbin Zhou]

Since commit 40cd01a9c324("efi/loongarch: libstub: remove dependency on
flattened DT"), we can parse the FDT from efi system table.

And now, LoongArch is coming to support booting with FDT, so we adds the
relevant booting support as well as parameter parsing.

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
---
 arch/loongarch/Kconfig             |  2 +
 arch/loongarch/include/asm/efi.h   |  1 +
 arch/loongarch/include/asm/setup.h |  1 +
 arch/loongarch/kernel/acpi.c       | 11 +++++-
 arch/loongarch/kernel/efi.c        | 19 +++++++++-
 arch/loongarch/kernel/env.c        |  3 ++
 arch/loongarch/kernel/reset.c      |  3 +-
 arch/loongarch/kernel/setup.c      | 61 +++++++++++++++++++++++++++++-
 arch/loongarch/kernel/smp.c        | 32 ++++++++++++++++
 arch/loongarch/pci/acpi.c          |  5 ++-
 10 files changed, 131 insertions(+), 7 deletions(-)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 5c4f1dc87f84..ff6f2b7d0ec2 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -120,6 +120,8 @@ config LOONGARCH
 	select MODULES_USE_ELF_RELA if MODULES
 	select NEED_PER_CPU_EMBED_FIRST_CHUNK
 	select NEED_PER_CPU_PAGE_FIRST_CHUNK
+	select OF
+	select OF_EARLY_FLATTREE
 	select PCI
 	select PCI_DOMAINS_GENERIC
 	select PCI_ECAM if ACPI
diff --git a/arch/loongarch/include/asm/efi.h b/arch/loongarch/include/asm/efi.h
index 174567b00ddb..81e5d3371868 100644
--- a/arch/loongarch/include/asm/efi.h
+++ b/arch/loongarch/include/asm/efi.h
@@ -9,6 +9,7 @@
 
 void __init efi_init(void);
 void __init efi_runtime_init(void);
+void __init *efi_fdt_pointer(void);
 void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
 
 #define ARCH_EFI_IRQ_FLAGS_MASK  0x00000004  /* Bit 2: CSR.CRMD.IE */
diff --git a/arch/loongarch/include/asm/setup.h b/arch/loongarch/include/asm/setup.h
index ca373f8e3c4d..b18baf878ed4 100644
--- a/arch/loongarch/include/asm/setup.h
+++ b/arch/loongarch/include/asm/setup.h
@@ -13,6 +13,7 @@
 
 extern unsigned long eentry;
 extern unsigned long tlbrentry;
+extern char original_cmdline[COMMAND_LINE_SIZE];
 extern void tlb_init(int cpu);
 extern void cpu_cache_init(void);
 extern void cache_error_setup(void);
diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
index c435ce320c59..8fceda717598 100644
--- a/arch/loongarch/kernel/acpi.c
+++ b/arch/loongarch/kernel/acpi.c
@@ -13,6 +13,7 @@
 #include <linux/irqdomain.h>
 #include <linux/memblock.h>
 #include <linux/serial_core.h>
+#include <linux/of_fdt.h>
 #include <asm/io.h>
 #include <asm/numa.h>
 #include <asm/loongson.h>
@@ -151,14 +152,14 @@ void __init acpi_boot_table_init(void)
 	 * If acpi_disabled, bail out
 	 */
 	if (acpi_disabled)
-		return;
+		goto fdt_earlycon;
 
 	/*
 	 * Initialize the ACPI boot-time table parser.
 	 */
 	if (acpi_table_init()) {
 		disable_acpi();
-		return;
+		goto fdt_earlycon;
 	}
 
 	loongson_sysconf.boot_cpu_id = read_csr_cpuid();
@@ -170,6 +171,12 @@ void __init acpi_boot_table_init(void)
 
 	/* Do not enable ACPI SPCR console by default */
 	acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
+
+	return;
+
+fdt_earlycon:
+	if (earlycon_acpi_spcr_enable)
+		early_init_dt_scan_chosen_stdout();
 }
 
 #ifdef CONFIG_ACPI_NUMA
diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c
index a31329971133..dc6d52bc7700 100644
--- a/arch/loongarch/kernel/efi.c
+++ b/arch/loongarch/kernel/efi.c
@@ -27,17 +27,19 @@
 static unsigned long efi_nr_tables;
 static unsigned long efi_config_table;
 
-static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
+static unsigned long boot_memmap __initdata = EFI_INVALID_TABLE_ADDR;
+static unsigned long efi_fdt __initdata = EFI_INVALID_TABLE_ADDR;
 
 static efi_system_table_t *efi_systab;
 static efi_config_table_type_t arch_tables[] __initdata = {
 	{LINUX_EFI_BOOT_MEMMAP_GUID,	&boot_memmap,	"MEMMAP" },
+	{DEVICE_TREE_GUID,		&efi_fdt,	"EFIFDT" },
 	{},
 };
 
 void __init efi_runtime_init(void)
 {
-	if (!efi_enabled(EFI_BOOT))
+	if (!efi_enabled(EFI_BOOT) || !efi_systab->runtime)
 		return;
 
 	if (efi_runtime_disabled()) {
@@ -101,3 +103,16 @@ void __init efi_init(void)
 		early_memunmap(tbl, sizeof(*tbl));
 	}
 }
+
+void __init *efi_fdt_pointer(void)
+{
+	if (!efi_systab) {
+		pr_err("Can't find EFI system table.\n");
+		return NULL;
+	}
+
+	if (efi_fdt == EFI_INVALID_TABLE_ADDR)
+		return NULL;
+
+	return (void *)early_memremap_ro(efi_fdt, sizeof(efi_fdt));
+}
diff --git a/arch/loongarch/kernel/env.c b/arch/loongarch/kernel/env.c
index 6d56a463b091..4fd6eb9398b4 100644
--- a/arch/loongarch/kernel/env.c
+++ b/arch/loongarch/kernel/env.c
@@ -11,6 +11,7 @@
 #include <asm/early_ioremap.h>
 #include <asm/bootinfo.h>
 #include <asm/loongson.h>
+#include <asm/setup.h>
 
 u64 efi_system_table;
 struct loongson_system_configuration loongson_sysconf;
@@ -27,6 +28,8 @@ void __init init_environ(void)
 		clear_bit(EFI_BOOT, &efi.flags);
 
 	strscpy(boot_command_line, cmdline, COMMAND_LINE_SIZE);
+	/* Save unparsed command line copy for FDT */
+	strscpy(original_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 	early_memunmap(cmdline, COMMAND_LINE_SIZE);
 
 	efi_system_table = fw_arg2;
diff --git a/arch/loongarch/kernel/reset.c b/arch/loongarch/kernel/reset.c
index 9fad889a3c1b..1ef8c6383535 100644
--- a/arch/loongarch/kernel/reset.c
+++ b/arch/loongarch/kernel/reset.c
@@ -44,7 +44,8 @@ void machine_power_off(void)
 	smp_send_stop();
 #endif
 #ifdef CONFIG_PM
-	enable_pci_wakeup();
+	if (!acpi_disabled)
+		enable_pci_wakeup();
 #endif
 	do_kernel_power_off();
 #ifdef CONFIG_EFI
diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index 01ed0c3f0c78..6bc1b9b0186d 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -30,6 +30,9 @@
 #include <linux/dma-map-ops.h>
 #include <linux/suspend.h>
 #include <linux/swiotlb.h>
+#include <linux/of_fdt.h>
+#include <linux/of_address.h>
+#include <linux/libfdt.h>
 
 #include <asm/addrspace.h>
 #include <asm/alternative.h>
@@ -70,6 +73,7 @@ static const char dmi_empty_string[] = "        ";
  *
  * These are initialized so they are in the .data section
  */
+char original_cmdline[COMMAND_LINE_SIZE] __initdata;
 
 static int num_standard_resources;
 static struct resource *standard_resources;
@@ -288,6 +292,36 @@ static void __init check_kernel_sections_mem(void)
 	}
 }
 
+static void __init bootcmdline_init(char **cmdline_p)
+{
+	/*
+	 * If CONFIG_CMDLINE_FORCE is enabled then initializing the command line
+	 * is trivial - we simply use the built-in command line unconditionally &
+	 * unmodified.
+	 */
+	if (IS_ENABLED(CONFIG_CMDLINE_FORCE)) {
+		strscpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+		return;
+	}
+
+#ifdef CONFIG_OF_FLATTREE
+	/*
+	 * If CONFIG_CMDLINE_BOOTLOADER is enabled and we are in FDT-based system,
+	 * the boot_command_line will be overwritten by early_init_dt_scan_chosen().
+	 * So we need to append original_cmdline(the original copy of
+	 * boot_command_line) to boot_command_line.
+	 */
+	if (initial_boot_params) {
+		if (boot_command_line[0])
+			strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
+
+		strlcat(boot_command_line, original_cmdline, COMMAND_LINE_SIZE);
+	}
+#endif
+
+	*cmdline_p = boot_command_line;
+}
+
 /*
  * arch_mem_init - initialize memory management subsystem
  */
@@ -298,6 +332,8 @@ static void __init arch_mem_init(char **cmdline_p)
 
 	check_kernel_sections_mem();
 
+	early_init_fdt_scan_reserved_mem();
+
 	/*
 	 * In order to reduce the possibility of kernel panic when failed to
 	 * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
@@ -424,20 +460,43 @@ static void __init prefill_possible_map(void)
 }
 #endif
 
+static void __init fdt_setup(void)
+{
+#ifdef CONFIG_OF_EARLY_FLATTREE
+	void *fdt_pointer;
+
+	/* ACPI-based systems do not require parsing fdt */
+	if (acpi_os_get_root_pointer())
+		return;
+
+	/* Look for a device tree configuration table entry */
+	fdt_pointer = efi_fdt_pointer();
+	if (!fdt_pointer || fdt_check_header(fdt_pointer))
+		return;
+
+	early_init_dt_scan(fdt_pointer);
+	early_init_fdt_reserve_self();
+
+	max_low_pfn = PFN_PHYS(memblock_end_of_DRAM());
+#endif
+}
+
 void __init setup_arch(char **cmdline_p)
 {
 	cpu_probe();
-	*cmdline_p = boot_command_line;
 
 	init_environ();
 	efi_init();
+	fdt_setup();
 	memblock_init();
 	pagetable_init();
+	bootcmdline_init(cmdline_p);
 	parse_early_param();
 	reserve_initrd_mem();
 
 	platform_init();
 	arch_mem_init(cmdline_p);
+	unflatten_and_copy_device_tree();
 
 	resource_init();
 #ifdef CONFIG_SMP
diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c
index 90ddcac0df9b..a0c7edb240d1 100644
--- a/arch/loongarch/kernel/smp.c
+++ b/arch/loongarch/kernel/smp.c
@@ -170,8 +170,40 @@ irqreturn_t loongson_ipi_interrupt(int irq, void *dev)
 	return IRQ_HANDLED;
 }
 
+static void __init fdt_smp_setup(void)
+{
+#ifdef CONFIG_OF
+	struct device_node *node = NULL;
+	unsigned int cpu, cpuid;
+
+	for_each_of_cpu_node(node) {
+		if (!of_device_is_available(node))
+			continue;
+
+		cpuid = of_get_cpu_hwid(node, 0);
+		if (cpuid >= nr_cpu_ids)
+			continue;
+
+		if (cpuid == loongson_sysconf.boot_cpu_id)
+			cpu = 0;
+		else
+			cpu = cpumask_next_zero(-1, cpu_present_mask);
+
+		num_processors++;
+		set_cpu_possible(cpu, true);
+		set_cpu_present(cpu, true);
+		__cpu_number_map[cpuid] = cpu;
+		__cpu_logical_map[cpu] = cpuid;
+	}
+
+	loongson_sysconf.nr_cpus = num_processors;
+#endif
+}
+
 void __init loongson_smp_setup(void)
 {
+	fdt_smp_setup();
+
 	cpu_data[0].core = cpu_logical_map(0) % loongson_sysconf.cores_per_package;
 	cpu_data[0].package = cpu_logical_map(0) / loongson_sysconf.cores_per_package;
 
diff --git a/arch/loongarch/pci/acpi.c b/arch/loongarch/pci/acpi.c
index 8235ec92b41f..dd7df7a985fd 100644
--- a/arch/loongarch/pci/acpi.c
+++ b/arch/loongarch/pci/acpi.c
@@ -27,9 +27,12 @@ void pcibios_add_bus(struct pci_bus *bus)
 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
 {
 	struct pci_config_window *cfg = bridge->bus->sysdata;
-	struct acpi_device *adev = to_acpi_device(cfg->parent);
+	struct acpi_device *adev = NULL;
 	struct device *bus_dev = &bridge->bus->dev;
 
+	if (!acpi_disabled)
+		adev = to_acpi_device(cfg->parent);
+
 	ACPI_COMPANION_SET(&bridge->dev, adev);
 	set_dev_node(bus_dev, pa_to_nid(cfg->res.start));
 
-- 
2.31.1

[PATCH V2 2/2] LoongArch: Process ISA Node in DeviceTree

[Binbin Zhou]

Previously, we are hardcoding reserved ISA I/O Space in, now we are
processing it I/O via DeviceTree directly.

The ranges property if ISA node is used to determine the size and
address of reserved I/O space.

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
---
 arch/loongarch/kernel/setup.c | 76 +++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
index 6bc1b9b0186d..d42a1461fd67 100644
--- a/arch/loongarch/kernel/setup.c
+++ b/arch/loongarch/kernel/setup.c
@@ -258,6 +258,82 @@ static void __init arch_parse_crashkernel(void)
 #endif
 }
 
+static int __init add_legacy_isa_io(struct fwnode_handle *fwnode, resource_size_t hw_start,
+				    resource_size_t size)
+{
+	int ret = 0;
+	struct logic_pio_hwaddr *range;
+	unsigned long vaddr;
+
+	range = kzalloc(sizeof(*range), GFP_ATOMIC);
+	if (!range)
+		return -ENOMEM;
+
+	range->fwnode = fwnode;
+	range->size = size = round_up(size, PAGE_SIZE);
+	range->hw_start = hw_start;
+	range->flags = LOGIC_PIO_CPU_MMIO;
+
+	ret = logic_pio_register_range(range);
+	if (ret) {
+		kfree(range);
+		return ret;
+	}
+
+	/* Legacy ISA must placed at the start of PCI_IOBASE */
+	if (range->io_start != 0) {
+		logic_pio_unregister_range(range);
+		kfree(range);
+		return -EINVAL;
+	}
+
+	vaddr = (unsigned long) (PCI_IOBASE + range->io_start);
+
+	ioremap_page_range(vaddr, vaddr + size, hw_start, pgprot_device(PAGE_KERNEL));
+
+	return 0;
+}
+
+static __init int arch_reserve_pio_range(void)
+{
+	struct device_node *np;
+
+	for_each_node_by_name(np, "isa") {
+		struct of_range range;
+		struct of_range_parser parser;
+
+		pr_info("ISA Bridge: %pOF\n", np);
+
+		if (of_range_parser_init(&parser, np)) {
+			pr_info("Failed to parse resources.\n");
+			of_node_put(np);
+			break;
+		}
+
+		for_each_of_range(&parser, &range) {
+			switch (range.flags & IORESOURCE_TYPE_BITS) {
+			case IORESOURCE_IO:
+				pr_info(" IO 0x%016llx..0x%016llx  ->  0x%016llx\n",
+					range.cpu_addr,
+					range.cpu_addr + range.size - 1,
+					range.bus_addr);
+				if (add_legacy_isa_io(&np->fwnode, range.cpu_addr, range.size))
+					pr_warn("Failed to reserve legacy IO in Logic PIO\n");
+				break;
+			case IORESOURCE_MEM:
+				pr_info(" MEM 0x%016llx..0x%016llx  ->  0x%016llx\n",
+					range.cpu_addr,
+					range.cpu_addr + range.size - 1,
+					range.bus_addr);
+				break;
+			}
+		}
+	}
+
+	return 0;
+}
+arch_initcall(arch_reserve_pio_range);
+
 void __init platform_init(void)
 {
 	arch_reserve_vmcore();
-- 
2.31.1