#include <linux/acpi.h>
#include <linux/arm-smccc.h>
+#include <linux/delay.h>
#include <linux/module.h>
#include <linux/platform_device.h>
[3] = "RMA",
};
+/* Mapped pointer for RSH_BOOT_FIFO_DATA and RSH_BOOT_FIFO_COUNT register. */
+static void __iomem *mlxbf_rsh_boot_data;
+static void __iomem *mlxbf_rsh_boot_cnt;
+
/* ARM SMC call which is atomic and no need for lock. */
static int mlxbf_bootctl_smc(unsigned int smc_op, int smc_arg)
{
MODULE_DEVICE_TABLE(acpi, mlxbf_bootctl_acpi_ids);
+static ssize_t mlxbf_bootctl_bootfifo_read(struct file *filp,
+ struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t pos,
+ size_t count)
+{
+ unsigned long timeout = msecs_to_jiffies(500);
+ unsigned long expire = jiffies + timeout;
+ u64 data, cnt = 0;
+ char *p = buf;
+
+ while (count >= sizeof(data)) {
+ /* Give up reading if no more data within 500ms. */
+ if (!cnt) {
+ cnt = readq(mlxbf_rsh_boot_cnt);
+ if (!cnt) {
+ if (time_after(jiffies, expire))
+ break;
+ usleep_range(10, 50);
+ continue;
+ }
+ }
+
+ data = readq(mlxbf_rsh_boot_data);
+ memcpy(p, &data, sizeof(data));
+ count -= sizeof(data);
+ p += sizeof(data);
+ cnt--;
+ expire = jiffies + timeout;
+ }
+
+ return p - buf;
+}
+
+static struct bin_attribute mlxbf_bootctl_bootfifo_sysfs_attr = {
+ .attr = { .name = "bootfifo", .mode = 0400 },
+ .read = mlxbf_bootctl_bootfifo_read,
+};
+
static bool mlxbf_bootctl_guid_match(const guid_t *guid,
const struct arm_smccc_res *res)
{
guid_t guid;
int ret;
+ /* Get the resource of the bootfifo data register. */
+ mlxbf_rsh_boot_data = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mlxbf_rsh_boot_data))
+ return PTR_ERR(mlxbf_rsh_boot_data);
+
+ /* Get the resource of the bootfifo counter register. */
+ mlxbf_rsh_boot_cnt = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(mlxbf_rsh_boot_cnt))
+ return PTR_ERR(mlxbf_rsh_boot_cnt);
+
/* Ensure we have the UUID we expect for this service. */
arm_smccc_smc(MLXBF_BOOTCTL_SIP_SVC_UID, 0, 0, 0, 0, 0, 0, 0, &res);
guid_parse(mlxbf_bootctl_svc_uuid_str, &guid);
if (ret < 0)
dev_warn(&pdev->dev, "Unable to reset the EMMC boot mode\n");
+ ret = sysfs_create_bin_file(&pdev->dev.kobj,
+ &mlxbf_bootctl_bootfifo_sysfs_attr);
+ if (ret)
+ pr_err("Unable to create bootfifo sysfs file, error %d\n", ret);
+
+ return ret;
+}
+
+static int mlxbf_bootctl_remove(struct platform_device *pdev)
+{
+ sysfs_remove_bin_file(&pdev->dev.kobj,
+ &mlxbf_bootctl_bootfifo_sysfs_attr);
+
return 0;
}
static struct platform_driver mlxbf_bootctl_driver = {
.probe = mlxbf_bootctl_probe,
+ .remove = mlxbf_bootctl_remove,
.driver = {
.name = "mlxbf-bootctl",
.dev_groups = mlxbf_bootctl_groups,