drivers/firmware/arm_scmi/transports/smc.c

Source file repositories/reference/linux-study-clean/drivers/firmware/arm_scmi/transports/smc.c

File Facts

System
Linux kernel
Corpus path
drivers/firmware/arm_scmi/transports/smc.c
Extension
.c
Size
8810 bytes
Lines
314
Domain
Driver Families
Bucket
drivers/firmware
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct scmi_smc {
	int irq;
	struct scmi_chan_info *cinfo;
	struct scmi_shared_mem __iomem *shmem;
	struct scmi_shmem_io_ops *io_ops;
	/* Protect access to shmem area */
	struct mutex shmem_lock;
#define INFLIGHT_NONE	MSG_TOKEN_MAX
	atomic_t inflight;
	unsigned long func_id;
	unsigned long param_page;
	unsigned long param_offset;
	unsigned long cap_id;
};

static struct scmi_transport_core_operations *core;

static irqreturn_t smc_msg_done_isr(int irq, void *data)
{
	struct scmi_smc *scmi_info = data;

	core->rx_callback(scmi_info->cinfo,
			  core->shmem->read_header(scmi_info->shmem), NULL);

	return IRQ_HANDLED;
}

static bool smc_chan_available(struct device_node *of_node, int idx)
{
	struct device_node *np __free(device_node) =
					of_parse_phandle(of_node, "shmem", 0);
	if (!np)
		return false;

	return true;
}

static inline void smc_channel_lock_init(struct scmi_smc *scmi_info)
{
	if (IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE))
		atomic_set(&scmi_info->inflight, INFLIGHT_NONE);
	else
		mutex_init(&scmi_info->shmem_lock);
}

static bool smc_xfer_inflight(struct scmi_xfer *xfer, atomic_t *inflight)
{
	int ret;

	ret = atomic_cmpxchg(inflight, INFLIGHT_NONE, xfer->hdr.seq);

	return ret == INFLIGHT_NONE;
}

static inline void
smc_channel_lock_acquire(struct scmi_smc *scmi_info,
			 struct scmi_xfer *xfer __maybe_unused)
{
	if (IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE))
		spin_until_cond(smc_xfer_inflight(xfer, &scmi_info->inflight));
	else
		mutex_lock(&scmi_info->shmem_lock);
}

static inline void smc_channel_lock_release(struct scmi_smc *scmi_info)
{
	if (IS_ENABLED(CONFIG_ARM_SCMI_TRANSPORT_SMC_ATOMIC_ENABLE))
		atomic_set(&scmi_info->inflight, INFLIGHT_NONE);
	else
		mutex_unlock(&scmi_info->shmem_lock);
}

static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
			  bool tx)
{
	struct device *cdev = cinfo->dev;
	unsigned long cap_id = ULONG_MAX;
	struct scmi_smc *scmi_info;
	struct resource res = {};
	u32 func_id;
	int ret;

	if (!tx)
		return -ENODEV;

	scmi_info = devm_kzalloc(dev, sizeof(*scmi_info), GFP_KERNEL);
	if (!scmi_info)
		return -ENOMEM;

	scmi_info->shmem = core->shmem->setup_iomap(cinfo, dev, tx, &res,

Annotation

Implementation Notes