[PATCH] earlycon: rework common framework for earlycon declarations
From: Masahiro Yamada <hidden>
Date: 2016-02-12 09:28:39
Also in:
linux-arch, linux-devicetree, linux-serial, lkml
Subsystem:
generic include/asm header files, open firmware and flattened device tree, the rest, tty layer and serial drivers · Maintainers:
Arnd Bergmann, Rob Herring, Saravana Kannan, Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
Commit 71f50c6d9a22 ("of: drop symbols declared by _OF_DECLARE() from
modules") fixed the link error introduced by commit b8d20e06eaad
("serial: 8250_uniphier: add earlycon support").
After commit 2eaa790989e0 ("earlycon: Use common framework for
earlycon declarations") was applied, the link error came back
because the commit reworked OF_EARLYCON_DECLARE() to not use
_OF_DECLARE().
This commit reworks OF_EARLYCON_DECLARE() again based on
_OF_DECLARE(). My motivations are:
- Fix the link error in a generic way (without patching
drivers/tty/serial/8250/8250_uniphier.c)
- Delete struct earlycon_id. This struct is re-inventing the wheel;
the fields "name", "compatible", "setup" can be implemented in
struct of_device_id as other framework do.
The difference between OF_EARLYCON_DECLARE() and other users of
_OF_DECLARE is that OF_EARLYCON_DECLARE() needs to fill the "name"
field of struct of_device_id. To make it easier, a new macro
_OF_DECLARE_WITH_NAME() has been added. It fills the name field
with the given argument. On the other hand, _OF_DECLARE() sets the
"name" field to a null string; this is the same behavior as before.
Fixes: 2eaa790989e0 ("earlycon: Use common framework for earlycon declarations")
Signed-off-by: Masahiro Yamada <redacted>
---
I confirmed this patch can apply onto "next-20160212" tag of linux-next.
In order to apply it onto the "tty-next" branch of TTY subsytem,
Grag will have to pull v4.5-rc3 in.
drivers/of/fdt.c | 7 ++-----
drivers/tty/serial/earlycon.c | 19 +++++++++++++------
include/asm-generic/vmlinux.lds.h | 12 ++----------
include/linux/of.h | 22 +++++++++++++++-------
include/linux/serial_core.h | 23 +++++++----------------
5 files changed, 39 insertions(+), 44 deletions(-)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index e2295b2..ad262e9 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c@@ -802,7 +802,7 @@ static int __init early_init_dt_scan_chosen_serial(void) int offset; const char *p, *q, *options = NULL; int l; - const struct earlycon_id *match; + const struct of_device_id *match; const void *fdt = initial_boot_params; offset = fdt_path_offset(fdt, "/chosen");
@@ -829,10 +829,7 @@ static int __init early_init_dt_scan_chosen_serial(void) return 0; } - for (match = __earlycon_table; match < __earlycon_table_end; match++) { - if (!match->compatible[0]) - continue; - + for (match = __earlycon_of_table; match->compatible[0]; match++) { if (fdt_node_check_compatible(fdt, offset, match->compatible)) continue;
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 067783f..4888ced 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c@@ -38,6 +38,9 @@ static struct earlycon_device early_console_dev = { .con = &early_con, }; +static const struct of_device_id __earlycon_of_table_sentinel + __used __section(__earlycon_of_table_end); + static void __iomem * __init earlycon_map(unsigned long paddr, size_t size) { void __iomem *base;
@@ -127,9 +130,10 @@ static int __init parse_options(struct earlycon_device *device, char *options) return 0; } -static int __init register_earlycon(char *buf, const struct earlycon_id *match) +static int __init register_earlycon(char *buf, const struct of_device_id *match) { int err; + int (*setup)(struct earlycon_device *, const char *options); struct uart_port *port = &early_console_dev.port; /* On parsing error, pass the options buf to the setup function */
@@ -142,7 +146,8 @@ static int __init register_earlycon(char *buf, const struct earlycon_id *match) port->membase = earlycon_map(port->mapbase, 64); earlycon_init(&early_console_dev, match->name); - err = match->setup(&early_console_dev, buf); + setup = match->data; + err = setup(&early_console_dev, buf); if (err < 0) return err; if (!early_console_dev.con->write)
@@ -172,7 +177,7 @@ static int __init register_earlycon(char *buf, const struct earlycon_id *match) */ int __init setup_earlycon(char *buf) { - const struct earlycon_id *match; + const struct of_device_id *match; if (!buf || !buf[0]) return -EINVAL;
@@ -180,7 +185,7 @@ int __init setup_earlycon(char *buf) if (early_con.flags & CON_ENABLED) return -EALREADY; - for (match = __earlycon_table; match < __earlycon_table_end; match++) { + for (match = __earlycon_of_table; match->name[0]; match++) { size_t len = strlen(match->name); if (strncmp(buf, match->name, len))
@@ -220,12 +225,13 @@ early_param("earlycon", param_setup_earlycon); #ifdef CONFIG_OF_EARLY_FLATTREE -int __init of_setup_earlycon(const struct earlycon_id *match, +int __init of_setup_earlycon(const struct of_device_id *match, unsigned long node, const char *options) { int err; struct uart_port *port = &early_console_dev.port; + int (*setup)(struct earlycon_device *, const char *options); const __be32 *val; bool big_endian; u64 addr;
@@ -273,7 +279,8 @@ int __init of_setup_earlycon(const struct earlycon_id *match, sizeof(early_console_dev.options)); } earlycon_init(&early_console_dev, match->name); - err = match->setup(&early_console_dev, options); + setup = match->data; + err = setup(&early_console_dev, options); if (err < 0) return err; if (!early_console_dev.con->write)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index e9a81a6..699f4a5 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h@@ -153,15 +153,6 @@ #define TRACE_SYSCALLS() #endif -#ifdef CONFIG_SERIAL_EARLYCON -#define EARLYCON_TABLE() STRUCT_ALIGN(); \ - VMLINUX_SYMBOL(__earlycon_table) = .; \ - *(__earlycon_table) \ - VMLINUX_SYMBOL(__earlycon_table_end) = .; -#else -#define EARLYCON_TABLE() -#endif - #define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name) #define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name) #define OF_TABLE(cfg, name) __OF_TABLE(config_enabled(cfg), name)
@@ -179,6 +170,7 @@ #define RESERVEDMEM_OF_TABLES() OF_TABLE(CONFIG_OF_RESERVED_MEM, reservedmem) #define CPU_METHOD_OF_TABLES() OF_TABLE(CONFIG_SMP, cpu_method) #define CPUIDLE_METHOD_OF_TABLES() OF_TABLE(CONFIG_CPU_IDLE, cpuidle_method) +#define EARLYCON_OF_TABLES() OF_TABLE(CONFIG_SERIAL_EARLYCON, earlycon) #ifdef CONFIG_ACPI #define ACPI_PROBE_TABLE(name) \
@@ -525,7 +517,7 @@ IRQCHIP_OF_MATCH_TABLE() \ ACPI_PROBE_TABLE(irqchip) \ ACPI_PROBE_TABLE(clksrc) \ - EARLYCON_TABLE() + EARLYCON_OF_TABLES() #define INIT_TEXT \ *(.init.text) \
diff --git a/include/linux/of.h b/include/linux/of.h
index dc6e396..6e57245 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h@@ -930,19 +930,27 @@ static inline int of_get_available_child_count(const struct device_node *np) } #if defined(CONFIG_OF) && !defined(MODULE) -#define _OF_DECLARE(table, name, compat, fn, fn_type) \ - static const struct of_device_id __of_table_##name \ +#define __OF_DECLARE(table, name1, name2, compat, fn, fn_type) \ + static const struct of_device_id __UNIQUE_ID(__of_table_##name1)\ __used __section(__##table##_of_table) \ - = { .compatible = compat, \ + = { .name = name2, \ + .compatible = compat, \ .data = (fn == (fn_type)NULL) ? fn : fn } #else -#define _OF_DECLARE(table, name, compat, fn, fn_type) \ - static const struct of_device_id __of_table_##name \ +#define __OF_DECLARE(table, name1, name2, compat, fn, fn_type) \ + static const struct of_device_id __UNIQUE_ID(__of_table_##name1)\ __attribute__((unused)) \ - = { .compatible = compat, \ - .data = (fn == (fn_type)NULL) ? fn : fn } + = { .name = name2, \ + .compatible = compat, \ + .data = (fn == (fn_type)NULL) ? fn : fn } #endif +#define _OF_DECLARE(table, name, compat, fn, fn_type) \ + __OF_DECLARE(table, name, "", compat, fn, fn_type) + +#define _OF_DECLARE_WITH_NAME(table, name, compat, fn, fn_type) \ + __OF_DECLARE(table, name, __stringify(name), compat, fn, fn_type) + typedef int (*of_init_fn_2)(struct device_node *, struct device_node *); typedef void (*of_init_fn_1)(struct device_node *);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index cbfcf38..0f13160 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h@@ -24,6 +24,7 @@ #include <linux/compiler.h> #include <linux/interrupt.h> #include <linux/circ_buf.h> +#include <linux/mod_devicetable.h> #include <linux/spinlock.h> #include <linux/sched.h> #include <linux/tty.h>
@@ -340,26 +341,16 @@ struct earlycon_device { unsigned int baud; }; -struct earlycon_id { - char name[16]; - char compatible[128]; - int (*setup)(struct earlycon_device *, const char *options); -} __aligned(32); +extern const struct of_device_id __earlycon_of_table[]; -extern const struct earlycon_id __earlycon_table[]; -extern const struct earlycon_id __earlycon_table_end[]; +#define OF_EARLYCON_DECLARE(name, compat, fn) \ + _OF_DECLARE_WITH_NAME(earlycon, name, compat, fn, void *) -#define OF_EARLYCON_DECLARE(_name, compat, fn) \ - static const struct earlycon_id __UNIQUE_ID(__earlycon_##_name) \ - __used __section(__earlycon_table) \ - = { .name = __stringify(_name), \ - .compatible = compat, \ - .setup = fn } - -#define EARLYCON_DECLARE(_name, fn) OF_EARLYCON_DECLARE(_name, "", fn) +#define EARLYCON_DECLARE(_name, fn) \ + OF_EARLYCON_DECLARE(_name, "-earlycon-dummy-compat-string-", fn) extern int setup_earlycon(char *buf); -extern int of_setup_earlycon(const struct earlycon_id *match, +extern int of_setup_earlycon(const struct of_device_id *match, unsigned long node, const char *options);
--
1.9.1