Hello Simon,
On Sun, Oct 31, 2021 at 09:07:01PM -0600, Simon Glass wrote:
> This is a patch for Takahiro to look at, just for illustration. Not ready
> for review.
Thank you for posting the draft.
At a first glance, it looks good and I don't see any specific issue
with your implementation.
Since my code has already added DM_TAG support, I'm looking forward for
getting your final patch.
The only remaining issue is *modeling* partitions :)
-Takahiro Akashi
> To run the test:
>
> ./u-boot -T -c "ut common test_event_probe"
>
> Signed-off-by: Simon Glass <s...@chromium.org>
> ---
>
> common/Kconfig | 11 ++++
> common/Makefile | 2 +
> common/board_f.c | 2 +
> common/event.c | 103 ++++++++++++++++++++++++++++++
> common/log.c | 1 +
> drivers/core/device.c | 14 ++++
> include/asm-generic/global_data.h | 3 +
> include/event.h | 103 ++++++++++++++++++++++++++++++
> include/event_internal.h | 34 ++++++++++
> include/log.h | 2 +
> test/common/Makefile | 1 +
> test/common/event.c | 85 ++++++++++++++++++++++++
> test/test-main.c | 5 ++
> 13 files changed, 366 insertions(+)
> create mode 100644 common/event.c
> create mode 100644 include/event.h
> create mode 100644 include/event_internal.h
> create mode 100644 test/common/event.c
>
> diff --git a/common/Kconfig b/common/Kconfig
> index d6f77ab7b9c..54d0adaa8d5 100644
> --- a/common/Kconfig
> +++ b/common/Kconfig
> @@ -484,6 +484,17 @@ config DISPLAY_BOARDINFO_LATE
>
> menu "Start-up hooks"
>
> +config EVENT
> + bool "General-purpose event-handling mechanism"
> + default y if SANDBOX
> + help
> + This enables sending and processing of events, to allow interested
> + parties to be alerted when something happens. This is an attempt to
> + step the flow of weak functions, hooks, functions in board_f.c
> + and board_r.c and the Kconfig options below.
> +
> + See doc/develop/event.rst for more information.
> +
> config ARCH_EARLY_INIT_R
> bool "Call arch-specific init soon after relocation"
> help
> diff --git a/common/Makefile b/common/Makefile
> index e7839027b6c..1b4601ac13f 100644
> --- a/common/Makefile
> +++ b/common/Makefile
> @@ -101,6 +101,8 @@ obj-y += malloc_simple.o
> endif
> endif
>
> +obj-$(CONFIG_EVENT) += event.o
> +
> obj-y += image.o image-board.o
> obj-$(CONFIG_$(SPL_TPL_)HASH) += hash.o
> obj-$(CONFIG_ANDROID_AB) += android_ab.o
> diff --git a/common/board_f.c b/common/board_f.c
> index 3dc0eaa59c5..faf262d564c 100644
> --- a/common/board_f.c
> +++ b/common/board_f.c
> @@ -19,6 +19,7 @@
> #include <dm.h>
> #include <env.h>
> #include <env_internal.h>
> +#include <event.h>
> #include <fdtdec.h>
> #include <fs.h>
> #include <hang.h>
> @@ -820,6 +821,7 @@ static const init_fnc_t init_sequence_f[] = {
> initf_malloc,
> log_init,
> initf_bootstage, /* uses its own timer, so does not need DM */
> + event_init,
> #ifdef CONFIG_BLOBLIST
> bloblist_init,
> #endif
> diff --git a/common/event.c b/common/event.c
> new file mode 100644
> index 00000000000..428628da44d
> --- /dev/null
> +++ b/common/event.c
> @@ -0,0 +1,103 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Events provide a general-purpose way to react to / subscribe to changes
> + * within U-Boot
> + *
> + * Copyright 2021 Google LLC
> + * Written by Simon Glass <s...@chromium.org>
> + */
> +
> +#define LOG_CATEGORY LOGC_EVENT
> +
> +#include <common.h>
> +#include <event.h>
> +#include <event_internal.h>
> +#include <log.h>
> +#include <malloc.h>
> +#include <asm/global_data.h>
> +#include <linux/list.h>
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +static void spy_free(struct event_spy *spy)
> +{
> + list_del(&spy->sibling_node);
> +}
> +
> +int event_register(const char *id, enum event_t type, event_handler_t func,
> void *ctx)
> +{
> + struct event_state *state = gd->event_state;
> + struct event_spy *spy;
> +
> + spy = malloc(sizeof(*spy));
> + if (!spy)
> + return log_msg_ret("alloc", -ENOMEM);
> +
> + spy->id = id;
> + spy->type = type;
> + spy->func = func;
> + spy->ctx = ctx;
> + list_add_tail(&spy->sibling_node, &state->spy_head);
> +
> + return 0;
> +}
> +
> +int event_notify(enum event_t type, void *data, int size)
> +{
> + struct event_state *state = gd->event_state;
> + struct event_spy *spy, *next;
> + struct event event;
> +
> + event.type = type;
> + if (size > sizeof(event.data))
> + return log_msg_ret("size", -E2BIG);
> + memcpy(&event.data, data, size);
> + list_for_each_entry_safe(spy, next, &state->spy_head, sibling_node) {
> + if (spy->type == type) {
> + int ret;
> +
> + log_debug("Sending event %x to spy '%s'\n", type,
> + spy->id);
> + ret = spy->func(spy->ctx, &event);
> +
> + /*
> + * TODO: Handle various return codes to
> + *
> + * - claim an event (no others will see it)
> + * - return an error from the event
> + */
> + if (ret)
> + return log_msg_ret("spy", ret);
> + }
> + }
> +
> + return 0;
> +}
> +
> +int event_uninit(void)
> +{
> + struct event_state *state = gd->event_state;
> + struct event_spy *spy, *next;
> +
> + if (!state)
> + return 0;
> + list_for_each_entry_safe(spy, next, &state->spy_head, sibling_node)
> + spy_free(spy);
> +
> + return 0;
> +}
> +
> +int event_init(void)
> +{
> + struct event_state *state;
> +
> + state = malloc(sizeof(struct event_state));
> + if (!state)
> + return log_msg_ret("alloc", -ENOMEM);
> +
> + INIT_LIST_HEAD(&state->spy_head);
> +
> + gd->event_state = state;
> +
> + return 0;
> +}
> diff --git a/common/log.c b/common/log.c
> index 1aaa6c1527b..aa2e780d2d7 100644
> --- a/common/log.c
> +++ b/common/log.c
> @@ -28,6 +28,7 @@ static const char *const log_cat_name[] = {
> "devres",
> "acpi",
> "boot",
> + "event",
> };
>
> _Static_assert(ARRAY_SIZE(log_cat_name) == LOGC_COUNT - LOGC_NONE,
> diff --git a/drivers/core/device.c b/drivers/core/device.c
> index efd07176e37..c52b47d5cc1 100644
> --- a/drivers/core/device.c
> +++ b/drivers/core/device.c
> @@ -10,6 +10,7 @@
>
> #include <common.h>
> #include <cpu_func.h>
> +#include <event.h>
> #include <log.h>
> #include <asm/global_data.h>
> #include <asm/io.h>
> @@ -482,6 +483,11 @@ static int device_get_dma_constraints(struct udevice
> *dev)
> return 0;
> }
>
> +static int device_notify(const struct udevice *dev, enum event_t type)
> +{
> + return event_notify(type, &dev, sizeof(dev));
> +}
> +
> int device_probe(struct udevice *dev)
> {
> const struct driver *drv;
> @@ -493,6 +499,10 @@ int device_probe(struct udevice *dev)
> if (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
> return 0;
>
> + ret = device_notify(dev, EVT_DM_PRE_PROBE);
> + if (ret)
> + return ret;
> +
> drv = dev->driver;
> assert(drv);
>
> @@ -589,6 +599,10 @@ int device_probe(struct udevice *dev)
> if (dev->parent && device_get_uclass_id(dev) == UCLASS_PINCTRL)
> pinctrl_select_state(dev, "default");
>
> + ret = device_notify(dev, EVT_DM_POST_PROBE);
> + if (ret)
> + return ret;
> +
> return 0;
> fail_uclass:
> if (device_remove(dev, DM_REMOVE_NORMAL)) {
> diff --git a/include/asm-generic/global_data.h
> b/include/asm-generic/global_data.h
> index 16fd305a65c..771cda57a58 100644
> --- a/include/asm-generic/global_data.h
> +++ b/include/asm-generic/global_data.h
> @@ -459,6 +459,9 @@ struct global_data {
> */
> char *smbios_version;
> #endif
> +#if CONFIG_IS_ENABLED(EVENT)
> + struct event_state *event_state;
> +#endif
> };
> #ifndef DO_DEPS_ONLY
> static_assert(sizeof(struct global_data) == GD_SIZE);
> diff --git a/include/event.h b/include/event.h
> new file mode 100644
> index 00000000000..d44fd53639a
> --- /dev/null
> +++ b/include/event.h
> @@ -0,0 +1,103 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Events provide a general-purpose way to react to / subscribe to changes
> + * within U-Boot
> + *
> + * Copyright 2021 Google LLC
> + * Written by Simon Glass <s...@chromium.org>
> + */
> +
> +#ifndef __event_h
> +#define __event_h
> +
> +/**
> + * enum event_t - Types of events supported by U-Boot
> + *
> + * @EVT_DM_PRE_PROBE: Device is about to be probed
> + */
> +enum event_t {
> + EVT_NONE,
> + EVT_TEST,
> +
> + /* Events related to driver model */
> + EVT_DM_PRE_PROBE,
> + EVT_DM_POST_PROBE,
> +
> + EVT_COUNT
> +};
> +
> +union event_data {
> + /**
> + * struct event_data_test - test data
> + *
> + * @signal: A value to update the state with
> + */
> + struct event_data_test {
> + int signal;
> + } test;
> +
> + /**
> + * struct event_dm - driver model event
> + *
> + * @dev: Device this event relates to
> + */
> + struct event_dm {
> + struct udevice *dev;
> + } dm;
> +};
> +
> +/**
> + * struct event - an event that can be sent and received
> + *
> + * @type: Event type
> + * @data: Data for this particular event
> + */
> +struct event {
> + enum event_t type;
> + union event_data data;
> +};
> +
> +/** Function type for event handlers */
> +typedef int (*event_handler_t)(void *ctx, struct event *event);
> +
> +/**
> + * event_register - register a new spy
> + *
> + * @id: Spy ID
> + * @type: Event type to subscribe to
> + * @func: Function to call when the event is sent
> + * @ctx: Context to pass to the function
> + * @return 0 if OK, -ve on erropr
> + */
> +int event_register(const char *id, enum event_t type, event_handler_t func,
> + void *ctx);
> +
> +/**
> + * event_notify() - notify spies about an event
> + *
> + * It is possible to pass in union event_data here but that may not be
> + * convenient if the data is elsewhere, or is one of the members of the
> union.
> + * So this uses a void * for @data, with a separate @size.
> + *
> + * @type: Event type
> + * @data: Event data to be sent (e.g. union_event_data)
> + * @size: Size of data in bytes
> + */
> +int event_notify(enum event_t type, void *data, int size);
> +
> +#if CONFIG_IS_ENABLED(EVENT)
> +int event_uninit(void);
> +int event_init(void);
> +#else
> +static int event_uninit(void)
> +{
> + return 0;
> +}
> +
> +static inline int event_init(void)
> +{
> + return 0;
> +}
> +#endif
> +
> +#endif
> diff --git a/include/event_internal.h b/include/event_internal.h
> new file mode 100644
> index 00000000000..19308453f7b
> --- /dev/null
> +++ b/include/event_internal.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Internal definitions for events
> + *
> + * Copyright 2021 Google LLC
> + * Written by Simon Glass <s...@chromium.org>
> + */
> +
> +#ifndef __event_internal_h
> +#define __event_internal_h
> +
> +#include <linux/list.h>
> +
> +/**
> + * struct event_spy - a spy that watches for an event of a particular type
> + *
> + * @id: Spy ID
> + * @type: Event type to subscribe to
> + * @func: Function to call when the event is sent
> + * @ctx: Context to pass to the function
> + */
> +struct event_spy {
> + struct list_head sibling_node;
> + const char *id;
> + enum event_t type;
> + event_handler_t func;
> + void *ctx;
> +};
> +
> +struct event_state {
> + struct list_head spy_head;
> +};
> +
> +#endif
> diff --git a/include/log.h b/include/log.h
> index e0e12ce1944..7169fff7aa5 100644
> --- a/include/log.h
> +++ b/include/log.h
> @@ -98,6 +98,8 @@ enum log_category_t {
> LOGC_ACPI,
> /** @LOGC_BOOT: Related to boot process / boot image processing */
> LOGC_BOOT,
> + /** @LOGC_EVENT: Related to event and event handling */
> + LOGC_EVENT,
> /** @LOGC_COUNT: Number of log categories */
> LOGC_COUNT,
> /** @LOGC_END: Sentinel value for lists of log categories */
> diff --git a/test/common/Makefile b/test/common/Makefile
> index 24c9145dccc..9087788ba6a 100644
> --- a/test/common/Makefile
> +++ b/test/common/Makefile
> @@ -1,3 +1,4 @@
> # SPDX-License-Identifier: GPL-2.0+
> obj-y += cmd_ut_common.o
> obj-$(CONFIG_AUTOBOOT) += test_autoboot.o
> +obj-$(CONFIG_EVENT) += event.o
> diff --git a/test/common/event.c b/test/common/event.c
> new file mode 100644
> index 00000000000..6f359e2a933
> --- /dev/null
> +++ b/test/common/event.c
> @@ -0,0 +1,85 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * Unit tests for event handling
> + *
> + * Copyright 2021 Google LLC
> + * Written by Simon Glass <s...@chromium.org>
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <event.h>
> +#include <test/common.h>
> +#include <test/test.h>
> +#include <test/ut.h>
> +
> +struct test_state {
> + struct udevice *dev;
> + int val;
> +};
> +
> +static int h_adder(void *ctx, struct event *event)
> +{
> + struct event_data_test *data = &event->data.test;
> + struct test_state *test_state = ctx;
> +
> + test_state->val += data->signal;
> +
> + return 0;
> +}
> +
> +static int test_event_base(struct unit_test_state *uts)
> +{
> + struct test_state state;
> + int signal;
> +
> + state.val = 12;
> + ut_assertok(event_register("wibble", EVT_TEST, h_adder, &state));
> +
> + signal = 17;
> +
> + /* Check that the handler is called */
> + ut_assertok(event_notify(EVT_TEST, &signal, sizeof(signal)));
> + ut_asserteq(12 + 17, state.val);
> +
> + return 0;
> +}
> +COMMON_TEST(test_event_base, 0);
> +
> +static int h_probe(void *ctx, struct event *event)
> +{
> + struct test_state *test_state = ctx;
> +
> + test_state->dev = event->data.dm.dev;
> + switch (event->type) {
> + case EVT_DM_PRE_PROBE:
> + test_state->val |= 1;
> + break;
> + case EVT_DM_POST_PROBE:
> + test_state->val |= 2;
> + break;
> + default:
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static int test_event_probe(struct unit_test_state *uts)
> +{
> + struct test_state state;
> + struct udevice *dev;
> +
> + state.val = 0;
> + ut_assertok(event_register("pre", EVT_DM_PRE_PROBE, h_probe, &state));
> + ut_assertok(event_register("post", EVT_DM_POST_PROBE, h_probe, &state));
> +
> + /* Probe a device */
> + ut_assertok(uclass_first_device_err(UCLASS_TEST_FDT, &dev));
> +
> + /* Check that the handler is called */
> + ut_asserteq(3, state.val);
> +
> + return 0;
> +}
> +COMMON_TEST(test_event_probe, UT_TESTF_DM | UT_TESTF_SCAN_FDT);
> diff --git a/test/test-main.c b/test/test-main.c
> index 3cdf6849c57..c3ccdf3fed8 100644
> --- a/test/test-main.c
> +++ b/test/test-main.c
> @@ -7,6 +7,7 @@
> #include <common.h>
> #include <console.h>
> #include <dm.h>
> +#include <event.h>
> #include <dm/root.h>
> #include <dm/test.h>
> #include <dm/uclass-internal.h>
> @@ -218,6 +219,9 @@ static int dm_test_restore(struct device_node *of_root)
> */
> static int test_pre_run(struct unit_test_state *uts, struct unit_test *test)
> {
> + gd->event_state = NULL;
> + ut_assertok(event_init());
> +
> if (test->flags & UT_TESTF_DM)
> ut_assertok(dm_test_pre_run(uts));
>
> @@ -260,6 +264,7 @@ static int test_post_run(struct unit_test_state *uts,
> struct unit_test *test)
> ut_unsilence_console(uts);
> if (test->flags & UT_TESTF_DM)
> ut_assertok(dm_test_post_run(uts));
> + ut_assertok(event_uninit());
>
> return 0;
> }
> --
> 2.33.1.1089.g2158813163f-goog
>
