zephyr/drivers/console/jailhouse_debug_console.c
Gerard Marull-Paretas a5fd0d184a init: remove the need for a dummy device pointer in SYS_INIT functions
The init infrastructure, found in `init.h`, is currently used by:

- `SYS_INIT`: to call functions before `main`
- `DEVICE_*`: to initialize devices

They are all sorted according to an initialization level + a priority.
`SYS_INIT` calls are really orthogonal to devices, however, the required
function signature requires a `const struct device *dev` as a first
argument. The only reason for that is because the same init machinery is
used by devices, so we have something like:

```c
struct init_entry {
	int (*init)(const struct device *dev);
	/* only set by DEVICE_*, otherwise NULL */
	const struct device *dev;
}
```

As a result, we end up with such weird/ugly pattern:

```c
static int my_init(const struct device *dev)
{
	/* always NULL! add ARG_UNUSED to avoid compiler warning */
	ARG_UNUSED(dev);
	...
}
```

This is really a result of poor internals isolation. This patch proposes
a to make init entries more flexible so that they can accept sytem
initialization calls like this:

```c
static int my_init(void)
{
	...
}
```

This is achieved using a union:

```c
union init_function {
	/* for SYS_INIT, used when init_entry.dev == NULL */
	int (*sys)(void);
	/* for DEVICE*, used when init_entry.dev != NULL */
	int (*dev)(const struct device *dev);
};

struct init_entry {
	/* stores init function (either for SYS_INIT or DEVICE*)
	union init_function init_fn;
	/* stores device pointer for DEVICE*, NULL for SYS_INIT. Allows
	 * to know which union entry to call.
	 */
	const struct device *dev;
}
```

This solution **does not increase ROM usage**, and allows to offer clean
public APIs for both SYS_INIT and DEVICE*. Note that however, init
machinery keeps a coupling with devices.

**NOTE**: This is a breaking change! All `SYS_INIT` functions will need
to be converted to the new signature. See the script offered in the
following commit.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

init: convert SYS_INIT functions to the new signature

Conversion scripted using scripts/utils/migrate_sys_init.py.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

manifest: update projects for SYS_INIT changes

Update modules with updated SYS_INIT calls:

- hal_ti
- lvgl
- sof
- TraceRecorderSource

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

tests: devicetree: devices: adjust test

Adjust test according to the recently introduced SYS_INIT
infrastructure.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

tests: kernel: threads: adjust SYS_INIT call

Adjust to the new signature: int (*init_fn)(void);

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2023-04-12 14:28:07 +00:00

58 lines
1.2 KiB
C

/*
* Copyright 2022 NXP
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/kernel.h>
#include <zephyr/sys/printk.h>
#include <zephyr/device.h>
#include <zephyr/init.h>
#if defined(CONFIG_PRINTK) || defined(CONFIG_STDOUT_CONSOLE)
/**
* @brief Output one character to SIMULATOR console
* @param c Character to output
* @return The character passed as input.
*/
static int console_out(int c)
{
register unsigned long x0 __asm__("x0") = 8;
register unsigned long x1 __asm__("x1") = c;
__asm__ volatile ("hvc #0x4a48\r\n"
: "+r" (x0), "+r" (x1) : : );
return c;
}
#endif
#if defined(CONFIG_STDOUT_CONSOLE)
extern void __stdout_hook_install(int (*hook)(int));
#else
#define __stdout_hook_install(x) \
do {/* nothing */ \
} while ((0))
#endif
#if defined(CONFIG_PRINTK)
extern void __printk_hook_install(int (*fn)(int));
#else
#define __printk_hook_install(x) \
do {/* nothing */ \
} while ((0))
#endif
/**
* @brief Initialize the console/debug port
* @return 0 if successful, otherwise failed.
*/
static int jailhouse_console_init(void)
{
__stdout_hook_install(console_out);
__printk_hook_install(console_out);
return 0;
}
SYS_INIT(jailhouse_console_init,
PRE_KERNEL_1,
CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);