diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/firmware/arm_scmi/smc.c | 42 |
1 files changed, 41 insertions, 1 deletions
diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c index 82a82a5dc86a..fcbe2677f84b 100644 --- a/drivers/firmware/arm_scmi/smc.c +++ b/drivers/firmware/arm_scmi/smc.c @@ -9,9 +9,11 @@ #include <linux/arm-smccc.h> #include <linux/device.h> #include <linux/err.h> +#include <linux/interrupt.h> #include <linux/mutex.h> #include <linux/of.h> #include <linux/of_address.h> +#include <linux/of_irq.h> #include <linux/slab.h> #include "common.h" @@ -23,6 +25,8 @@ * @shmem: Transmit/Receive shared memory area * @shmem_lock: Lock to protect access to Tx/Rx shared memory area * @func_id: smc/hvc call function id + * @irq: Optional; employed when platforms indicates msg completion by intr. + * @tx_complete: Optional, employed only when irq is valid. */ struct scmi_smc { @@ -30,8 +34,19 @@ struct scmi_smc { struct scmi_shared_mem __iomem *shmem; struct mutex shmem_lock; u32 func_id; + int irq; + struct completion tx_complete; }; +static irqreturn_t smc_msg_done_isr(int irq, void *data) +{ + struct scmi_smc *scmi_info = data; + + complete(&scmi_info->tx_complete); + + return IRQ_HANDLED; +} + static bool smc_chan_available(struct device *dev, int idx) { struct device_node *np = of_parse_phandle(dev->of_node, "shmem", 0); @@ -51,7 +66,7 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, struct resource res; struct device_node *np; u32 func_id; - int ret; + int ret, irq; if (!tx) return -ENODEV; @@ -79,6 +94,24 @@ static int smc_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, if (ret < 0) return ret; + /* + * If there is an interrupt named "a2p", then the service and + * completion of a message is signaled by an interrupt rather than by + * the return of the SMC call. + */ + irq = of_irq_get_byname(cdev->of_node, "a2p"); + if (irq > 0) { + ret = devm_request_irq(dev, irq, smc_msg_done_isr, + IRQF_NO_SUSPEND, + dev_name(dev), scmi_info); + if (ret) { + dev_err(dev, "failed to setup SCMI smc irq\n"); + return ret; + } + init_completion(&scmi_info->tx_complete); + scmi_info->irq = irq; + } + scmi_info->func_id = func_id; scmi_info->cinfo = cinfo; mutex_init(&scmi_info->shmem_lock); @@ -110,7 +143,14 @@ static int smc_send_message(struct scmi_chan_info *cinfo, shmem_tx_prepare(scmi_info->shmem, xfer); + if (scmi_info->irq) + reinit_completion(&scmi_info->tx_complete); + arm_smccc_1_1_invoke(scmi_info->func_id, 0, 0, 0, 0, 0, 0, 0, &res); + + if (scmi_info->irq) + wait_for_completion(&scmi_info->tx_complete); + scmi_rx_callback(scmi_info->cinfo, shmem_read_header(scmi_info->shmem)); mutex_unlock(&scmi_info->shmem_lock); |