prom.c

linux 内核源代码

}

/*
 * ibm,pa-features is a per-cpu property that contains a string of
 * attribute descriptors, each of which has a 2 byte header plus up
 * to 254 bytes worth of processor attribute bits.  First header
 * byte specifies the number of bytes following the header.
 * Second header byte is an "attribute-specifier" type, of which
 * zero is the only currently-defined value.
 * Implementation:  Pass in the byte and bit offset for the feature
 * that we are interested in.  The function will return -1 if the
 * pa-features property is missing, or a 1/0 to indicate if the feature
 * is supported/not supported.  Note that the bit numbers are
 * big-endian to match the definition in PAPR.
 */
static struct ibm_pa_feature {
	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
	unsigned char	pabyte;		/* byte number in ibm,pa-features */
	unsigned char	pabit;		/* bit number (big-endian) */
	unsigned char	invert;		/* if 1, pa bit set => clear feature */
} ibm_pa_features[] __initdata = {
	{0, PPC_FEATURE_HAS_MMU,	0, 0, 0},
	{0, PPC_FEATURE_HAS_FPU,	0, 1, 0},
	{CPU_FTR_SLB, 0,		0, 2, 0},
	{CPU_FTR_CTRL, 0,		0, 3, 0},
	{CPU_FTR_NOEXECUTE, 0,		0, 6, 0},
	{CPU_FTR_NODSISRALIGN, 0,	1, 1, 1},
	{CPU_FTR_CI_LARGE_PAGE, 0,	1, 2, 0},
	{CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
};

static void __init scan_features(unsigned long node, unsigned char *ftrs,
				 unsigned long tablelen,
				 struct ibm_pa_feature *fp,
				 unsigned long ft_size)
{
	unsigned long i, len, bit;

	/* find descriptor with type == 0 */
	for (;;) {
		if (tablelen < 3)
			return;
		len = 2 + ftrs[0];
		if (tablelen < len)
			return;		/* descriptor 0 not found */
		if (ftrs[1] == 0)
			break;
		tablelen -= len;
		ftrs += len;
	}

	/* loop over bits we know about */
	for (i = 0; i < ft_size; ++i, ++fp) {
		if (fp->pabyte >= ftrs[0])
			continue;
		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
		if (bit ^ fp->invert) {
			cur_cpu_spec->cpu_features |= fp->cpu_features;
			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
		} else {
			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
		}
	}
}

static void __init check_cpu_pa_features(unsigned long node)
{
	unsigned char *pa_ftrs;
	unsigned long tablelen;

	pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
	if (pa_ftrs == NULL)
		return;

	scan_features(node, pa_ftrs, tablelen,
		      ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
}

static struct feature_property {
	const char *name;
	u32 min_value;
	unsigned long cpu_feature;
	unsigned long cpu_user_ftr;
} feature_properties[] __initdata = {
#ifdef CONFIG_ALTIVEC
	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_PPC64
	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
	{"ibm,purr", 1, CPU_FTR_PURR, 0},
	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
#endif /* CONFIG_PPC64 */
};

static void __init check_cpu_feature_properties(unsigned long node)
{
	unsigned long i;
	struct feature_property *fp = feature_properties;
	const u32 *prop;

	for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
		prop = of_get_flat_dt_prop(node, fp->name, NULL);
		if (prop && *prop >= fp->min_value) {
			cur_cpu_spec->cpu_features |= fp->cpu_feature;
			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
		}
	}
}

static int __init early_init_dt_scan_cpus(unsigned long node,
					  const char *uname, int depth,
					  void *data)
{
	static int logical_cpuid = 0;
	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
	const u32 *prop;
	const u32 *intserv;
	int i, nthreads;
	unsigned long len;
	int found = 0;

	/* We are scanning "cpu" nodes only */
	if (type == NULL || strcmp(type, "cpu") != 0)
		return 0;

	/* Get physical cpuid */
	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
	if (intserv) {
		nthreads = len / sizeof(int);
	} else {
		intserv = of_get_flat_dt_prop(node, "reg", NULL);
		nthreads = 1;
	}

	/*
	 * Now see if any of these threads match our boot cpu.
	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
	 */
	for (i = 0; i < nthreads; i++) {
		/*
		 * version 2 of the kexec param format adds the phys cpuid of
		 * booted proc.
		 */
		if (initial_boot_params && initial_boot_params->version >= 2) {
			if (intserv[i] ==
					initial_boot_params->boot_cpuid_phys) {
				found = 1;
				break;
			}
		} else {
			/*
			 * Check if it's the boot-cpu, set it's hw index now,
			 * unfortunately this format did not support booting
			 * off secondary threads.
			 */
			if (of_get_flat_dt_prop(node,
					"linux,boot-cpu", NULL) != NULL) {
				found = 1;
				break;
			}
		}

#ifdef CONFIG_SMP
		/* logical cpu id is always 0 on UP kernels */
		logical_cpuid++;
#endif
	}

	if (found) {
		DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
			intserv[i]);
		boot_cpuid = logical_cpuid;
		set_hard_smp_processor_id(boot_cpuid, intserv[i]);

		/*
		 * PAPR defines "logical" PVR values for cpus that
		 * meet various levels of the architecture:
		 * 0x0f000001	Architecture version 2.04
		 * 0x0f000002	Architecture version 2.05
		 * If the cpu-version property in the cpu node contains
		 * such a value, we call identify_cpu again with the
		 * logical PVR value in order to use the cpu feature
		 * bits appropriate for the architecture level.
		 *
		 * A POWER6 partition in "POWER6 architected" mode
		 * uses the 0x0f000002 PVR value; in POWER5+ mode
		 * it uses 0x0f000001.
		 */
		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
		if (prop && (*prop & 0xff000000) == 0x0f000000)
			identify_cpu(0, *prop);
#if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
		/*
		 * Since 440GR(x)/440EP(x) processors have the same pvr,
		 * we check the node path and set bit 28 in the cur_cpu_spec
		 * pvr for EP(x) processor version. This bit is always 0 in
		 * the "real" pvr. Then we call identify_cpu again with
		 * the new logical pvr to enable FPU support.
		 */
		if (strstr(uname, "440EP")) {
			identify_cpu(0, cur_cpu_spec->pvr_value | 0x8);
		}
#endif
	}

	check_cpu_feature_properties(node);
	check_cpu_pa_features(node);

#ifdef CONFIG_PPC_PSERIES
	if (nthreads > 1)
		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
	else
		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
#endif

	return 0;
}

#ifdef CONFIG_BLK_DEV_INITRD
static void __init early_init_dt_check_for_initrd(unsigned long node)
{
	unsigned long l;
	u32 *prop;

	DBG("Looking for initrd properties... ");

	prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
	if (prop) {
		initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));

		prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
		if (prop) {
			initrd_end = (unsigned long)
					__va(of_read_ulong(prop, l/4));
			initrd_below_start_ok = 1;
		} else {
			initrd_start = 0;
		}
	}

	DBG("initrd_start=0x%lx  initrd_end=0x%lx\n", initrd_start, initrd_end);
}
#else
static inline void early_init_dt_check_for_initrd(unsigned long node)
{
}
#endif /* CONFIG_BLK_DEV_INITRD */

static int __init early_init_dt_scan_chosen(unsigned long node,
					    const char *uname, int depth, void *data)
{
	unsigned long *lprop;
	unsigned long l;
	char *p;

	DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);

	if (depth != 1 ||
	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
		return 0;

#ifdef CONFIG_PPC64
	/* check if iommu is forced on or off */
	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
		iommu_is_off = 1;
	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
		iommu_force_on = 1;
#endif

	/* mem=x on the command line is the preferred mechanism */
 	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
 	if (lprop)
 		memory_limit = *lprop;

#ifdef CONFIG_PPC64
 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
 	if (lprop)
 		tce_alloc_start = *lprop;
 	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
 	if (lprop)
 		tce_alloc_end = *lprop;
#endif

#ifdef CONFIG_KEXEC
	lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
	if (lprop)
		crashk_res.start = *lprop;

	lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
	if (lprop)
		crashk_res.end = crashk_res.start + *lprop - 1;
#endif

	early_init_dt_check_for_initrd(node);

	/* Retreive command line */
 	p = of_get_flat_dt_prop(node, "bootargs", &l);
	if (p != NULL && l > 0)
		strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));

#ifdef CONFIG_CMDLINE
	if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
		strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#endif /* CONFIG_CMDLINE */

	DBG("Command line is: %s\n", cmd_line);

	/* break now */
	return 1;
}

static int __init early_init_dt_scan_root(unsigned long node,
					  const char *uname, int depth, void *data)
{
	u32 *prop;

	if (depth != 0)
		return 0;

	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
	dt_root_size_cells = (prop == NULL) ? 1 : *prop;
	DBG("dt_root_size_cells = %x\n", dt_root_size_cells);

	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
	dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
	DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
	
	/* break now */
	return 1;
}

static unsigned long __init dt_mem_next_cell(int s, cell_t **cellp)
{
	cell_t *p = *cellp;

	*cellp = p + s;
	return of_read_ulong(p, s);
}

#ifdef CONFIG_PPC_PSERIES
/*
 * Interpret the ibm,dynamic-memory property in the
 * /ibm,dynamic-reconfiguration-memory node.
 * This contains a list of memory blocks along with NUMA affinity
 * information.
 */
static int __init early_init_dt_scan_drconf_memory(unsigned long node)
{
	cell_t *dm, *ls;
	unsigned long l, n;
	unsigned long base, size, lmb_size, flags;

	ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
	if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
		return 0;
	lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);

	dm = (cell_t *)of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
	if (dm == NULL || l < sizeof(cell_t))
		return 0;

	n = *dm++;	/* number of entries */
	if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
		return 0;

	for (; n != 0; --n) {
		base = dt_mem_next_cell(dt_root_addr_cells, &dm);
		flags = dm[3];
		/* skip DRC index, pad, assoc. list index, flags */
		dm += 4;
		/* skip this block if the reserved bit is set in flags (0x80)
		   or if the block is not assigned to this partition (0x8) */
		if ((flags & 0x80) || !(flags & 0x8))
			continue;
		size = lmb_size;
		if (iommu_is_off) {
			if (base >= 0x80000000ul)
				continue;
			if ((base + size) > 0x80000000ul)
				size = 0x80000000ul - base;
		}
		lmb_add(base, size);
	}
	lmb_dump_all();
	return 0;
}
#else
#define early_init_dt_scan_drconf_memory(node)	0
#endif /* CONFIG_PPC_PSERIES */

static int __init early_init_dt_scan_memory(unsigned long node,
					    const char *uname, int depth, void *data)
{
	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
	cell_t *reg, *endp;
	unsigned long l;

	/* Look for the ibm,dynamic-reconfiguration-memory node */
	if (depth == 1 &&
	    strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
		return early_init_dt_scan_drconf_memory(node);

	/* We are scanning "memory" nodes only */
	if (type == NULL) {
		/*
		 * The longtrail doesn't have a device_type on the
		 * /memory node, so look for the node called /memory@0.
		 */
		if (depth != 1 || strcmp(uname, "memory@0") != 0)
			return 0;
	} else if (strcmp(type, "memory") != 0)
		return 0;

	reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
	if (reg == NULL)
		reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
	if (reg == NULL)
		return 0;

	endp = reg + (l / sizeof(cell_t));

	DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
	    uname, l, reg[0], reg[1], reg[2], reg[3]);

	while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
		unsigned long base, size;

		base = dt_mem_next_cell(dt_root_addr_cells, &reg);
		size = dt_mem_next_cell(dt_root_size_cells, &reg);

		if (size == 0)
			continue;
		DBG(" - %lx ,  %lx\n", base, size);
#ifdef CONFIG_PPC64
		if (iommu_is_off) {
			if (base >= 0x80000000ul)
				continue;
			if ((base + size) > 0x80000000ul)
				size = 0x80000000ul - base;
		}
#endif
		lmb_add(base, size);
	}
	return 0;
}

static void __init early_reserve_mem(void)
{
	u64 base, size;
	u64 *reserve_map;
	unsigned long self_base;
	unsigned long self_size;

	reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
					initial_boot_params->off_mem_rsvmap);

	/* before we do anything, lets reserve the dt blob */
	self_base = __pa((unsigned long)initial_boot_params);
	self_size = initial_boot_params->totalsize;
	lmb_reserve(self_base, self_size);

#ifdef CONFIG_BLK_DEV_INITRD
	/* then reserve the initrd, if any */
	if (initrd_start && (initrd_end > initrd_start))
		lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
#endif /* CONFIG_BLK_DEV_INITRD */

#ifdef CONFIG_PPC32
	/* 
	 * Handle the case where we might be booting from an old kexec
	 * image that setup the mem_rsvmap as pairs of 32-bit values
	 */
	if (*reserve_map > 0xffffffffull) {
		u32 base_32, size_32;
		u32 *reserve_map_32 = (u32 *)reserve_map;

		while (1) {
			base_32 = *(reserve_map_32++);
			size_32 = *(reserve_map_32++);
			if (size_32 == 0)
				break;
			/* skip if the reservation is for the blob */
			if (base_32 == self_base && size_32 == self_size)
				continue;
			DBG("reserving: %x -> %x\n", base_32, size_32);
			lmb_reserve(base_32, size_32);
		}
		return;
	}
#endif
	while (1) {
		base = *(reserve_map++);
		size = *(reserve_map++);
		if (size == 0)
			break;
		DBG("reserving: %llx -> %llx\n", base, size);
		lmb_reserve(base, size);
	}

#if 0
	DBG("memory reserved, lmbs :\n");
      	lmb_dump_all();