Re: [PATCH V15 04/12] MIPS: Loongson: Add UEFI-like firmware interface support

[Aurelien Jarno <aurelien@aurel32.net>]

On Sun, Dec 15, 2013 at 08:14:28PM +0800, Huacai Chen wrote:
> The new UEFI-like firmware interface has 3 advantages:
> 
> 1, Firmware export a physical memory map which is similar to X86's
>    E820 map, so prom_init_memory() will be more elegant that #ifdef
>    clauses can be removed.
> 2, Firmware export a pci irq routing table, we no longer need pci
>    irq routing fixup in kernel's code.
> 3, Firmware has a built-in vga bios, and its address is exported,
>    the linux kernel no longer need an embedded blob.
> 
> With the new interface, Loongson-3A/2G and all their successors can use
> a unified kernel. All Loongson-based machines support this new interface
> except 2E/2F series.
> 
> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> Signed-off-by: Hongliang Tao <taohl@lemote.com>
> Signed-off-by: Hua Yan <yanh@lemote.com>
> ---
>  arch/mips/include/asm/mach-loongson/boot_param.h |  151 ++++++++++++++++++++++
>  arch/mips/include/asm/mach-loongson/loongson.h   |    4 +-
>  arch/mips/loongson/common/env.c                  |   67 ++++++++--
>  arch/mips/loongson/common/init.c                 |    9 +-
>  arch/mips/loongson/common/mem.c                  |   42 ++++++
>  arch/mips/loongson/common/pci.c                  |    6 +-
>  arch/mips/loongson/common/reset.c                |   16 +++
>  7 files changed, 275 insertions(+), 20 deletions(-)
>  create mode 100644 arch/mips/include/asm/mach-loongson/boot_param.h
> 
> diff --git a/arch/mips/include/asm/mach-loongson/boot_param.h b/arch/mips/include/asm/mach-loongson/boot_param.h
> new file mode 100644
> index 0000000..4c5a1ba
> --- /dev/null
> +++ b/arch/mips/include/asm/mach-loongson/boot_param.h
> @@ -0,0 +1,151 @@
> +#ifndef __ASM_MACH_LOONGSON_BOOT_PARAM_H_
> +#define __ASM_MACH_LOONGSON_BOOT_PARAM_H_
> +
> +#define SYSTEM_RAM_LOW		1
> +#define SYSTEM_RAM_HIGH		2
> +#define MEM_RESERVED		3
> +#define PCI_IO			4
> +#define PCI_MEM			5
> +#define LOONGSON_CFG_REG	6
> +#define VIDEO_ROM		7
> +#define ADAPTER_ROM		8
> +#define ACPI_TABLE		9
> +#define MAX_MEMORY_TYPE		10
> +
> +#define LOONGSON3_BOOT_MEM_MAP_MAX 128
> +struct efi_memory_map_loongson{
> +	u16 vers;	/* version of efi_memory_map */
> +	u32 nr_map;	/* number of memory_maps */
> +	u32 mem_freq;	/* memory frequence */
> +	struct mem_map{
> +		u32 node_id;	/* node_id which memory attached to */
> +		u32 mem_type;	/* system memory, pci memory, pci io, etc. */
> +		u64 mem_start;	/* memory map start address */
> +		u32 mem_size;	/* each memory_map size, not the total size */
> +	}map[LOONGSON3_BOOT_MEM_MAP_MAX];
> +}__attribute__((packed));
> +
> +enum loongson_cpu_type
> +{
> +	Loongson_2E,
> +	Loongson_2F,
> +	Loongson_3A,
> +	Loongson_3B,
> +	Loongson_1A,
> +	Loongson_1B
> +};

Given it's an interface, you should probably number the different member
of the enum:

        Loongson_2E = 0,
        Loongson_2F = 1,
	...

> +/*
> + * Capability and feature descriptor structure for MIPS CPU
> + */
> +struct efi_cpuinfo_loongson {
> +	u16 vers;     /* version of efi_cpuinfo_loongson */
> +	u32 processor_id; /* PRID, e.g. 6305, 6306 */
> +	enum loongson_cpu_type cputype; /* 3A, 3B, etc. */

Actually I am not sure using an enum here is a good idea. An enum is
guaranteed to accept at least an int value, but the compiler is free
to reduce it to a shorter type if it knows all the values can fit.
While it might work now, it might not work in a future.

I think the correct size here is u32, you should probably use that
instead.

> +	u32 total_node;   /* num of total numa nodes */
> +	u32 cpu_startup_core_id; /* Core id */
> +	u32 cpu_clock_freq; /* cpu_clock */
> +	u32 nr_cpus;
> +}__attribute__((packed));
> +
> +struct system_loongson{
> +	u16 vers;     /* version of system_loongson */
> +	u32 ccnuma_smp; /* 0: no numa; 1: has numa */
> +	u32 sing_double_channel; /* 1:single; 2:double */
> +}__attribute__((packed));
> +
> +struct irq_source_routing_table {
> +	u16 vers;
> +	u16 size;
> +	u16 rtr_bus;
> +	u16 rtr_devfn;
> +	u32 vendor;
> +	u32 device;
> +	u32 PIC_type;   /* conform use HT or PCI to route to CPU-PIC */
> +	u64 ht_int_bit; /* 3A: 1<<24; 3B: 1<<16 */
> +	u64 ht_enable;  /* irqs used in this PIC */
> +	u32 node_id;    /* node id: 0x0-0; 0x1-1; 0x10-2; 0x11-3 */
> +	u64 pci_mem_start_addr;
> +	u64 pci_mem_end_addr;
> +	u64 pci_io_start_addr;
> +	u64 pci_io_end_addr;
> +	u64 pci_config_addr;
> +}__attribute__((packed));
> +
> +struct interface_info{
> +	u16 vers; /* version of the specificition */
> +	u16 size;
> +	u8  flag;
> +	char description[64];
> +}__attribute__((packed));
> +
> +#define MAX_RESOURCE_NUMBER 128
> +struct resource_loongson {
> +	u64 start; /* resource start address */
> +	u64 end;   /* resource end address */
> +	char name[64];
> +	u32 flags;
> +};
> +
> +struct archdev_data {};  /* arch specific additions */
> +
> +struct board_devices{
> +	char name[64];    /* hold the device name */
> +	u32 num_resources; /* number of device_resource */
> +	struct resource_loongson resource[MAX_RESOURCE_NUMBER]; /* for each device's resource */
> +	/* arch specific additions */
> +	struct archdev_data archdata;
> +};
> +
> +struct loongson_special_attribute{
> +	u16 vers;     /* version of this special */
> +	char special_name[64]; /* special_atribute_name */
> +	u32 loongson_special_type; /* type of special device */
> +	struct resource_loongson resource[MAX_RESOURCE_NUMBER]; /* for each device's resource */
> +};
> +
> +struct loongson_params{
> +	u64 memory_offset;	/* efi_memory_map_loongson struct offset */
> +	u64 cpu_offset;		/* efi_cpuinfo_loongson struct offset */
> +	u64 system_offset;	/* system_loongson struct offset */
> +	u64 irq_offset; 	/* irq_source_routing_table struct offset */
> +	u64 interface_offset;	/* interface_info struct offset */
> +	u64 special_offset;	/* loongson_special_attribute struct offset */
> +	u64 boarddev_table_offset;  /* board_devices offset */
> +};
> +
> +struct smbios_tables {
> +	u16 vers;     /* version of smbios */
> +	u64 vga_bios; /* vga_bios address */
> +	struct loongson_params lp;
> +};
> +
> +struct efi_reset_system_t{
> +	u64 ResetCold;
> +	u64 ResetWarm;
> +	u64 ResetType;
> +	u64 Shutdown;
> +};
> +
> +struct efi_loongson {
> +	u64 mps;	/* MPS table */
> +	u64 acpi;	/* ACPI table (IA64 ext 0.71) */
> +	u64 acpi20;	/* ACPI table (ACPI 2.0) */
> +	struct smbios_tables smbios;	/* SM BIOS table */
> +	u64 sal_systab;	/* SAL system table */
> +	u64 boot_info;	/* boot info table */
> +};
> +
> +struct boot_params{
> +	struct efi_loongson efi;
> +	struct efi_reset_system_t reset_system;
> +};
> +
> +extern u32 nr_cpus_loongson;
> +extern enum loongson_cpu_type cputype;
> +extern struct efi_memory_map_loongson *emap;
> +extern u64 ht_control_base;
> +extern u64 pci_mem_start_addr, pci_mem_end_addr;
> +extern u64 loongson_pciio_base;
> +extern u64 vgabios_addr;
> +#endif

That's a lot of external variables. What about using a big struct
containing all the struct above instead? That will also give access
to some values that are currently not exported.

> diff --git a/arch/mips/include/asm/mach-loongson/loongson.h b/arch/mips/include/asm/mach-loongson/loongson.h
> index b286534..5913ea0 100644
> --- a/arch/mips/include/asm/mach-loongson/loongson.h
> +++ b/arch/mips/include/asm/mach-loongson/loongson.h
> @@ -24,8 +24,8 @@ extern void mach_prepare_reboot(void);
>  extern void mach_prepare_shutdown(void);
>  
>  /* environment arguments from bootloader */
> -extern unsigned long cpu_clock_freq;
> -extern unsigned long memsize, highmemsize;
> +extern u32 cpu_clock_freq;
> +extern u32 memsize, highmemsize;
>  
>  /* loongson-specific command line, env and memory initialization */
>  extern void __init prom_init_memory(void);
> diff --git a/arch/mips/loongson/common/env.c b/arch/mips/loongson/common/env.c
> index 0a18fcf..dad9f0c 100644
> --- a/arch/mips/loongson/common/env.c
> +++ b/arch/mips/loongson/common/env.c
> @@ -18,37 +18,53 @@
>   * option) any later version.
>   */
>  #include <linux/module.h>
> -
>  #include <asm/bootinfo.h>
> -
>  #include <loongson.h>
> +#include <boot_param.h>
> +
> +struct boot_params *boot_p;
> +struct loongson_params *loongson_p;
> +
> +struct efi_cpuinfo_loongson *ecpu;
> +struct efi_memory_map_loongson *emap;
> +struct system_loongson *esys;
> +struct irq_source_routing_table *eirq_source;
> +
> +u64 ht_control_base;
> +u64 pci_mem_start_addr, pci_mem_end_addr;
> +u64 loongson_pciio_base;
> +u64 vgabios_addr;
> +u64 poweroff_addr, restart_addr;
>  
> -unsigned long cpu_clock_freq;
> +enum loongson_cpu_type cputype;
> +unsigned int nr_cpus_loongson = NR_CPUS;
> +
> +u32 cpu_clock_freq;
>  EXPORT_SYMBOL(cpu_clock_freq);
> -unsigned long memsize, highmemsize;
>  
>  #define parse_even_earlier(res, option, p)				\
>  do {									\
>  	unsigned int tmp __maybe_unused;				\
>  									\
>  	if (strncmp(option, (char *)p, strlen(option)) == 0)		\
> -		tmp = strict_strtol((char *)p + strlen(option"="), 10, &res); \
> +		tmp = kstrtou32((char *)p + strlen(option"="), 10, &res); \
>  } while (0)
>  
>  void __init prom_init_env(void)
>  {
>  	/* pmon passes arguments in 32bit pointers */
> -	int *_prom_envp;
> -	unsigned long bus_clock;
>  	unsigned int processor_id;
> +
> +#ifndef CONFIG_UEFI_FIRMWARE_INTERFACE

While "UEFI like" is probably a good idea to describe what is this
interface, it's clearly not an UEFI interface, so using UEFI is
misleading. Does this interface has a name? Could it be called
CONFIG_PMON_FIRMWARE_INTERFACE for example?

Also if you have a #if #else #endif sequence, it's probably better to
start with #ifdef instead of #ifndef.


> +	int *_prom_envp;
>  	long l;
> +	extern u32 memsize, highmemsize;
>  
>  	/* firmware arguments are initialized in head.S */
>  	_prom_envp = (int *)fw_arg2;
>  
>  	l = (long)*_prom_envp;
>  	while (l != 0) {
> -		parse_even_earlier(bus_clock, "busclock", l);
>  		parse_even_earlier(cpu_clock_freq, "cpuclock", l);
>  		parse_even_earlier(memsize, "memsize", l);
>  		parse_even_earlier(highmemsize, "highmemsize", l);
> @@ -57,8 +73,32 @@ void __init prom_init_env(void)
>  	}
>  	if (memsize == 0)
>  		memsize = 256;
> -	if (bus_clock == 0)
> -		bus_clock = 66000000;

I guess you removed bus_clock because it's only used for display,
correct?

> +#else
> +	/* firmware arguments are initialized in head.S */
> +	boot_p = (struct boot_params *)fw_arg2;
> +	loongson_p = &(boot_p->efi.smbios.lp);
> +
> +	ecpu	= (struct efi_cpuinfo_loongson *)((u64)loongson_p + loongson_p->cpu_offset);
> +	emap	= (struct efi_memory_map_loongson *)((u64)loongson_p + loongson_p->memory_offset);
> +	eirq_source = (struct irq_source_routing_table *)((u64)loongson_p + loongson_p->irq_offset);
> +
> +	cputype = ecpu->cputype;
> +	nr_cpus_loongson = ecpu->nr_cpus;
> +	cpu_clock_freq = ecpu->cpu_clock_freq;
> +	if (nr_cpus_loongson > NR_CPUS || nr_cpus_loongson == 0)
> +		nr_cpus_loongson = NR_CPUS;
> +
> +	pci_mem_start_addr = eirq_source->pci_mem_start_addr;
> +	pci_mem_end_addr = eirq_source->pci_mem_end_addr;
> +	loongson_pciio_base = eirq_source->pci_io_start_addr;

Instead of using intermediate variables, wouldn't it be possible to use
eirq_source directly?

> +
> +	poweroff_addr = boot_p->reset_system.Shutdown;
> +	restart_addr = boot_p->reset_system.ResetWarm;

Same there.

> +	pr_info("Shutdown Addr: %llx Reset Addr: %llx\n", poweroff_addr, restart_addr);

Hmm, this looks like debugging info which should probably be removed.

> +
> +	ht_control_base = 0x90000EFDFB000000; /* has no interface now */
> +	vgabios_addr = boot_p->efi.smbios.vga_bios;
> +#endif
>  	if (cpu_clock_freq == 0) {
>  		processor_id = (&current_cpu_data)->processor_id;
>  		switch (processor_id & PRID_REV_MASK) {
> @@ -68,12 +108,13 @@ void __init prom_init_env(void)
>  		case PRID_REV_LOONGSON2F:
>  			cpu_clock_freq = 797000000;
>  			break;
> +		case PRID_REV_LOONGSON3A:
> +			cpu_clock_freq = 900000000;
> +			break;
>  		default:
>  			cpu_clock_freq = 100000000;
>  			break;
>  		}
>  	}
> -
> -	pr_info("busclock=%ld, cpuclock=%ld, memsize=%ld, highmemsize=%ld\n",
> -		bus_clock, cpu_clock_freq, memsize, highmemsize);
> +	pr_info("CpuClock = %u\n", cpu_clock_freq);

Why removing memsize and highmemsize? That can be actually quite useful.

>  }
> diff --git a/arch/mips/loongson/common/init.c b/arch/mips/loongson/common/init.c
> index ae7af1f..81ba3b4 100644
> --- a/arch/mips/loongson/common/init.c
> +++ b/arch/mips/loongson/common/init.c
> @@ -17,10 +17,6 @@ unsigned long __maybe_unused _loongson_addrwincfg_base;
>  
>  void __init prom_init(void)
>  {
> -	/* init base address of io space */
> -	set_io_port_base((unsigned long)
> -		ioremap(LOONGSON_PCIIO_BASE, LOONGSON_PCIIO_SIZE));
> -
>  #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
>  	_loongson_addrwincfg_base = (unsigned long)
>  		ioremap(LOONGSON_ADDRWINCFG_BASE, LOONGSON_ADDRWINCFG_SIZE);
> @@ -28,6 +24,11 @@ void __init prom_init(void)
>  
>  	prom_init_cmdline();
>  	prom_init_env();
> +
> +	/* init base address of io space */
> +	set_io_port_base((unsigned long)
> +		ioremap(LOONGSON_PCIIO_BASE, LOONGSON_PCIIO_SIZE));
> +
>  	prom_init_memory();
>  
>  	/*init the uart base address */
> diff --git a/arch/mips/loongson/common/mem.c b/arch/mips/loongson/common/mem.c
> index 8626a42..406246b 100644
> --- a/arch/mips/loongson/common/mem.c
> +++ b/arch/mips/loongson/common/mem.c
> @@ -11,9 +11,14 @@
>  #include <asm/bootinfo.h>
>  
>  #include <loongson.h>
> +#include <boot_param.h>
>  #include <mem.h>
>  #include <pci.h>
>  
> +#ifndef CONFIG_UEFI_FIRMWARE_INTERFACE
> +

Same comment as above.

> +u32 memsize, highmemsize;
> +
>  void __init prom_init_memory(void)
>  {
>  	add_memory_region(0x0, (memsize << 20), BOOT_MEM_RAM);
> @@ -49,6 +54,43 @@ void __init prom_init_memory(void)
>  #endif /* !CONFIG_64BIT */
>  }
>  
> +#else /* CONFIG_UEFI_FIRMWARE_INTERFACE */
> +
> +void __init prom_init_memory(void)
> +{
> +	int i;
> +	u32 node_id;
> +	u32 mem_type;
> +
> +	/* parse memory information */
> +	for (i = 0; i < emap->nr_map; i++){
> +		node_id = emap->map[i].node_id;
> +		mem_type = emap->map[i].mem_type;
> +
> +		if (node_id == 0) {
> +			switch (mem_type) {
> +			case SYSTEM_RAM_LOW:
> +				add_memory_region(emap->map[i].mem_start,
> +					(u64)emap->map[i].mem_size << 20,
> +					BOOT_MEM_RAM);
> +				break;
> +			case SYSTEM_RAM_HIGH:
> +				add_memory_region(emap->map[i].mem_start,
> +					(u64)emap->map[i].mem_size << 20,
> +					BOOT_MEM_RAM);
> +				break;
> +			case MEM_RESERVED:
> +				add_memory_region(emap->map[i].mem_start,
> +					(u64)emap->map[i].mem_size << 20,
> +					BOOT_MEM_RESERVED);
> +				break;
> +			}
> +		}
> +	}
> +}
> +
> +#endif /* CONFIG_UEFI_FIRMWARE_INTERFACE */
> +
>  /* override of arch/mips/mm/cache.c: __uncached_access */
>  int __uncached_access(struct file *file, unsigned long addr)
>  {
> diff --git a/arch/mips/loongson/common/pci.c b/arch/mips/loongson/common/pci.c
> index fa77844..a06fd5f 100644
> --- a/arch/mips/loongson/common/pci.c
> +++ b/arch/mips/loongson/common/pci.c
> @@ -11,6 +11,7 @@
>  
>  #include <pci.h>
>  #include <loongson.h>
> +#include <boot_param.h>
>  
>  static struct resource loongson_pci_mem_resource = {
>  	.name	= "pci memory space",
> @@ -82,7 +83,10 @@ static int __init pcibios_init(void)
>  	setup_pcimap();
>  
>  	loongson_pci_controller.io_map_base = mips_io_port_base;
> -
> +#ifdef CONFIG_UEFI_FIRMWARE_INTERFACE
> +	loongson_pci_mem_resource.start = pci_mem_start_addr;
> +	loongson_pci_mem_resource.end = pci_mem_end_addr;
> +#endif
>  	register_pci_controller(&loongson_pci_controller);
>  
>  	return 0;

This part should probably be in patch 5 ("Add HT-linked PCI support").
Also it's a big strange defining a value in loongson_pci_mem_resource
from LOONGSON_PCI_MEM_START and LOONGSON_PCI_MEM_END, and later
overwriting it. Couldn't it be written only once?

> diff --git a/arch/mips/loongson/common/reset.c b/arch/mips/loongson/common/reset.c
> index 65bfbb5..9453565 100644
> --- a/arch/mips/loongson/common/reset.c
> +++ b/arch/mips/loongson/common/reset.c
> @@ -37,17 +37,33 @@ static inline void loongson_reboot(void)
>  
>  static void loongson_restart(char *command)
>  {
> +#ifndef CONFIG_UEFI_FIRMWARE_INTERFACE
>  	/* do preparation for reboot */
>  	mach_prepare_reboot();

Couldn't it be possible to provide an empty mach_prepare_reboot()? There
are already some Loongson 2 machines for which nothing is done in 
mach_prepare_reboot().

>  	/* reboot via jumping to boot base address */
>  	loongson_reboot();
> +#else
> +	extern u64 restart_addr;
> +	void (*fw_restart)(void) = (void *)restart_addr;
> +
> +	fw_restart();
> +	while (1) {}

This is basically jumping to restart_addr, while loongson_reboot is
basically a jump to LOONGSON_BOOT_BASE. Couldn't it be possible to
share some more code here?

> +#endif
>  }
>  
>  static void loongson_poweroff(void)
>  {
> +#ifndef CONFIG_UEFI_FIRMWARE_INTERFACE
>  	mach_prepare_shutdown();
>  	unreachable();
> +#else
> +	extern u64 poweroff_addr;
> +	void (*fw_poweroff)(void) = (void *)poweroff_addr;
> +
> +	fw_poweroff();
> +	while (1) {}
> +#endif

Same kind of comments here, wouldn't it be possible to move
all this code into a loongson 3 specific mach_prepare_shutdown?

>  }
>  
>  static void loongson_halt(void)
> -- 
> 1.7.7.3
> 
> 
> 

-- 
Aurelien Jarno	                        GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net