[PATCH RFC v3 14/35] of: fdt: Return the region size in of_flat_dt_translate_address()

Alexandru Elisei
2024-01-25T16:45:24Z

Alongside the base address, arm64 will also need to know the size of a
tag storage region. Teach of_flat_dt_translate_address() to parse and
return the size.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
---

Changes since rfc v2:

* New patch, suggested by Rob Herring.

arch/sh/kernel/cpu/sh2/probe.c | 2 +-
drivers/of/fdt_address.c | 12 +++++++++---
drivers/tty/serial/earlycon.c | 2 +-
include/linux/of_fdt.h | 2 +-
4 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/arch/sh/kernel/cpu/sh2/probe.c b/arch/sh/kernel/cpu/sh2/probe.c
index 70a07f4f2142..fa8904e8f390 100644
--- a/arch/sh/kernel/cpu/sh2/probe.c
+++ b/arch/sh/kernel/cpu/sh2/probe.c
@@ -21,7 +21,7 @@ static int __init scan_cache(unsigned long node, const char *uname,
if (!of_flat_dt_is_compatible(node, "jcore,cache"))
return 0;

- j2_ccr_base = ioremap(of_flat_dt_translate_address(node), 4);
+ j2_ccr_base = ioremap(of_flat_dt_translate_address(node, NULL), 4);

return 1;
}
diff --git a/drivers/of/fdt_address.c b/drivers/of/fdt_address.c
index 1dc15ab78b10..4c077778d710 100644
--- a/drivers/of/fdt_address.c
+++ b/drivers/of/fdt_address.c
@@ -160,7 +160,8 @@ static int __init fdt_translate_one(const void *blob, int parent,
* that can be mapped to a cpu physical address). This is not really specified
* that way, but this is traditionally the way IBM at least do things
*/
-static u64 __init fdt_translate_address(const void *blob, int node_offset)
+static u64 __init fdt_translate_address(const void *blob, int node_offset,
+ u64 *out_size)
{
int parent, len;
const struct of_bus *bus, *pbus;
@@ -193,6 +194,9 @@ static u64 __init fdt_translate_address(const void *blob, int node_offset)
goto bail;
}
memcpy(addr, reg, na * 4);
+ /* The size of the region doesn't need translating. */
+ if (out_size)
+ *out_size = of_read_number(reg + na, ns);

pr_debug("bus (na=%d, ns=%d) on %s\n",
na, ns, fdt_get_name(blob, parent, NULL));
@@ -242,8 +246,10 @@ static u64 __init fdt_translate_address(const void *blob, int node_offset)
/**
* of_flat_dt_translate_address - translate DT addr into CPU phys addr
* @node: node in the flat blob
+ * @out_size: size of the region, can be NULL if not needed
+ * @return: the address, OF_BAD_ADDR in case of error
*/
-u64 __init of_flat_dt_translate_address(unsigned long node)
+u64 __init of_flat_dt_translate_address(unsigned long node, u64 *out_size)
{
- return fdt_translate_address(initial_boot_params, node);
+ return fdt_translate_address(initial_boot_params, node, out_size);
}
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index a5fbb6ed38ae..e941cf786232 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -265,7 +265,7 @@ int __init of_setup_earlycon(const struct earlycon_id *match,

spin_lock_init(&port->lock);
port->iotype = UPIO_MEM;
- addr = of_flat_dt_translate_address(node);
+ addr = of_flat_dt_translate_address(node, NULL);
if (addr == OF_BAD_ADDR) {
pr_warn("[%s] bad address\n", match->name);
return -ENXIO;
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index d69ad5bb1eb1..0e26f8c3b10e 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -36,7 +36,7 @@ extern char __dtb_start[];
extern char __dtb_end[];

/* Other Prototypes */
-extern u64 of_flat_dt_translate_address(unsigned long node);
+extern u64 of_flat_dt_translate_address(unsigned long node, u64 *out_size);
extern void of_fdt_limit_memory(int limit);
#endif /* CONFIG_OF_FLATTREE */

--
2.43.0