[PATCH v17 08/10] of: fdt: Aggregate the processing of "linux,usable-memory-range"

Zhen Lei
2021-12-10T06:57:04Z

Currently, we parse the "linux,usable-memory-range" property in
early_init_dt_scan_chosen(), to obtain the specified memory range of the
crash kernel. We then reserve the required memory after
early_init_dt_scan_memory() has identified all available physical memory.
Because the two pieces of code are separated far, the readability and
maintainability are reduced. So bring them together.

Suggested-by: Rob Herring <robh@kernel.org>
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Tested-by: Dave Kleikamp <dave.kleikamp@oracle.com>
---
drivers/of/fdt.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index bdca35284cebd56..37b477a51175359 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -965,8 +965,7 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
elfcorehdr_addr, elfcorehdr_size);
}

-static phys_addr_t cap_mem_addr;
-static phys_addr_t cap_mem_size;
+static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;

/**
* early_init_dt_check_for_usable_mem_range - Decode usable memory range
@@ -977,6 +976,11 @@ static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)
{
const __be32 *prop;
int len;
+ phys_addr_t cap_mem_addr;
+ phys_addr_t cap_mem_size;
+
+ if ((long)node < 0)
+ return;

pr_debug("Looking for usable-memory-range property... ");

@@ -989,6 +993,8 @@ static void __init early_init_dt_check_for_usable_mem_range(unsigned long node)

pr_debug("cap_mem_start=%pa cap_mem_size=%pa\n", &cap_mem_addr,
&cap_mem_size);
+
+ memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
}

#ifdef CONFIG_SERIAL_EARLYCON
@@ -1137,9 +1143,10 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
(strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
return 0;

+ chosen_node_offset = node;
+
early_init_dt_check_for_initrd(node);
early_init_dt_check_for_elfcorehdr(node);
- early_init_dt_check_for_usable_mem_range(node);

/* Retrieve command line */
p = of_get_flat_dt_prop(node, "bootargs", &l);
@@ -1275,7 +1282,7 @@ void __init early_init_dt_scan_nodes(void)
of_scan_flat_dt(early_init_dt_scan_memory, NULL);

/* Handle linux,usable-memory-range property */
- memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
+ early_init_dt_check_for_usable_mem_range(chosen_node_offset);
}

bool __init early_init_dt_scan(void *params)
--
2.25.1