Commit 54c180e7 authored by Rob Herring's avatar Rob Herring
Browse files

of: Move all FDT reserved-memory handling into of_reserved_mem.c 



The split of /reserved-memory handling between fdt.c and
of_reserved_mem.c makes for reading and restructuring the code
difficult. As of_reserved_mem.c is only built for
CONFIG_OF_EARLY_FLATTREE already, move all the code to one spot.

Acked-by: default avatarSaravana Kannan <saravanak@google.com>
Reviewed-by: default avatarOreoluwa Babatunde <quic_obabatun@quicinc.com>
Link: https://lore.kernel.org/r/20240311181303.1516514-2-robh@kernel.org


Signed-off-by: default avatarRob Herring <robh@kernel.org>
parent 893ecc6d

drivers/of/fdt.c

+1 −122
Original line number Diff line number Diff line
@@ -17,7 +17,6 @@ 
#include <linux/mutex.h>

#include <linux/of.h>

#include <linux/of_fdt.h>

#include <linux/of_reserved_mem.h>

#include <linux/sizes.h>

#include <linux/string.h>

#include <linux/errno.h>
@@ -88,7 +87,7 @@ void __init of_fdt_limit_memory(int limit) 
	}

}



static bool of_fdt_device_is_available(const void *blob, unsigned long node)

bool of_fdt_device_is_available(const void *blob, unsigned long node)

{

	const char *status = fdt_getprop(blob, node, "status", NULL);
@@ -484,126 +483,6 @@ void *initial_boot_params __ro_after_init; 


static u32 of_fdt_crc32;



static int __init early_init_dt_reserve_memory(phys_addr_t base,

					       phys_addr_t size, bool nomap)

{

	if (nomap) {

		/*

		 * If the memory is already reserved (by another region), we

		 * should not allow it to be marked nomap, but don't worry

		 * if the region isn't memory as it won't be mapped.

		 */

		if (memblock_overlaps_region(&memblock.memory, base, size) &&

		    memblock_is_region_reserved(base, size))

			return -EBUSY;



		return memblock_mark_nomap(base, size);

	}

	return memblock_reserve(base, size);

}



/*

 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property

 */

static int __init __reserved_mem_reserve_reg(unsigned long node,

					     const char *uname)

{

	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);

	phys_addr_t base, size;

	int len;

	const __be32 *prop;

	int first = 1;

	bool nomap;



	prop = of_get_flat_dt_prop(node, "reg", &len);

	if (!prop)

		return -ENOENT;



	if (len && len % t_len != 0) {

		pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",

		       uname);

		return -EINVAL;

	}



	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;



	while (len >= t_len) {

		base = dt_mem_next_cell(dt_root_addr_cells, &prop);

		size = dt_mem_next_cell(dt_root_size_cells, &prop);



		if (size &&

		    early_init_dt_reserve_memory(base, size, nomap) == 0)

			pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",

				uname, &base, (unsigned long)(size / SZ_1M));

		else

			pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",

			       uname, &base, (unsigned long)(size / SZ_1M));



		len -= t_len;

		if (first) {

			fdt_reserved_mem_save_node(node, uname, base, size);

			first = 0;

		}

	}

	return 0;

}



/*

 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided

 * in /reserved-memory matches the values supported by the current implementation,

 * also check if ranges property has been provided

 */

static int __init __reserved_mem_check_root(unsigned long node)

{

	const __be32 *prop;



	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);

	if (!prop || be32_to_cpup(prop) != dt_root_size_cells)

		return -EINVAL;



	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);

	if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)

		return -EINVAL;



	prop = of_get_flat_dt_prop(node, "ranges", NULL);

	if (!prop)

		return -EINVAL;

	return 0;

}



/*

 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory

 */

static int __init fdt_scan_reserved_mem(void)

{

	int node, child;

	const void *fdt = initial_boot_params;



	node = fdt_path_offset(fdt, "/reserved-memory");

	if (node < 0)

		return -ENODEV;



	if (__reserved_mem_check_root(node) != 0) {

		pr_err("Reserved memory: unsupported node format, ignoring\n");

		return -EINVAL;

	}



	fdt_for_each_subnode(child, fdt, node) {

		const char *uname;

		int err;



		if (!of_fdt_device_is_available(fdt, child))

			continue;



		uname = fdt_get_name(fdt, child, NULL);



		err = __reserved_mem_reserve_reg(child, uname);

		if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))

			fdt_reserved_mem_save_node(child, uname, 0, 0);

	}

	return 0;

}



/*

 * fdt_reserve_elfcorehdr() - reserves memory for elf core header

 *

drivers/of/of_private.h

+3 −2
Original line number Diff line number Diff line
@@ -175,8 +175,9 @@ static inline struct device_node *__of_get_dma_parent(const struct device_node * 
}

#endif



int fdt_scan_reserved_mem(void);

void fdt_init_reserved_mem(void);

void fdt_reserved_mem_save_node(unsigned long node, const char *uname,

			       phys_addr_t base, phys_addr_t size);



bool of_fdt_device_is_available(const void *blob, unsigned long node);



#endif /* _LINUX_OF_PRIVATE_H */

drivers/of/of_reserved_mem.c

+123 −2
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#define pr_fmt(fmt)	"OF: reserved mem: " fmt



#include <linux/err.h>

#include <linux/libfdt.h>

#include <linux/of.h>

#include <linux/of_fdt.h>

#include <linux/of_platform.h>
@@ -58,7 +59,7 @@ static int __init early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, 
/*

 * fdt_reserved_mem_save_node() - save fdt node for second pass initialization

 */

void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,

static void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname,

					      phys_addr_t base, phys_addr_t size)

{

	struct reserved_mem *rmem = &reserved_mem[reserved_mem_count];
@@ -77,6 +78,126 @@ void __init fdt_reserved_mem_save_node(unsigned long node, const char *uname, 
	return;

}



static int __init early_init_dt_reserve_memory(phys_addr_t base,

					       phys_addr_t size, bool nomap)

{

	if (nomap) {

		/*

		 * If the memory is already reserved (by another region), we

		 * should not allow it to be marked nomap, but don't worry

		 * if the region isn't memory as it won't be mapped.

		 */

		if (memblock_overlaps_region(&memblock.memory, base, size) &&

		    memblock_is_region_reserved(base, size))

			return -EBUSY;



		return memblock_mark_nomap(base, size);

	}

	return memblock_reserve(base, size);

}



/*

 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property

 */

static int __init __reserved_mem_reserve_reg(unsigned long node,

					     const char *uname)

{

	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);

	phys_addr_t base, size;

	int len;

	const __be32 *prop;

	int first = 1;

	bool nomap;



	prop = of_get_flat_dt_prop(node, "reg", &len);

	if (!prop)

		return -ENOENT;



	if (len && len % t_len != 0) {

		pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",

		       uname);

		return -EINVAL;

	}



	nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;



	while (len >= t_len) {

		base = dt_mem_next_cell(dt_root_addr_cells, &prop);

		size = dt_mem_next_cell(dt_root_size_cells, &prop);



		if (size &&

		    early_init_dt_reserve_memory(base, size, nomap) == 0)

			pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",

				uname, &base, (unsigned long)(size / SZ_1M));

		else

			pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",

			       uname, &base, (unsigned long)(size / SZ_1M));



		len -= t_len;

		if (first) {

			fdt_reserved_mem_save_node(node, uname, base, size);

			first = 0;

		}

	}

	return 0;

}



/*

 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided

 * in /reserved-memory matches the values supported by the current implementation,

 * also check if ranges property has been provided

 */

static int __init __reserved_mem_check_root(unsigned long node)

{

	const __be32 *prop;



	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);

	if (!prop || be32_to_cpup(prop) != dt_root_size_cells)

		return -EINVAL;



	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);

	if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)

		return -EINVAL;



	prop = of_get_flat_dt_prop(node, "ranges", NULL);

	if (!prop)

		return -EINVAL;

	return 0;

}



/*

 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory

 */

int __init fdt_scan_reserved_mem(void)

{

	int node, child;

	const void *fdt = initial_boot_params;



	node = fdt_path_offset(fdt, "/reserved-memory");

	if (node < 0)

		return -ENODEV;



	if (__reserved_mem_check_root(node) != 0) {

		pr_err("Reserved memory: unsupported node format, ignoring\n");

		return -EINVAL;

	}



	fdt_for_each_subnode(child, fdt, node) {

		const char *uname;

		int err;



		if (!of_fdt_device_is_available(fdt, child))

			continue;



		uname = fdt_get_name(fdt, child, NULL);



		err = __reserved_mem_reserve_reg(child, uname);

		if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))

			fdt_reserved_mem_save_node(child, uname, 0, 0);

	}

	return 0;

}



/*

 * __reserved_mem_alloc_in_range() - allocate reserved memory described with

 *	'alloc-ranges'. Choose bottom-up/top-down depending on nearby existing