Add iMX lpuart driver to support tqma8xqp1gb

Signed-off-by: Ben Leslie <[email protected]>

elfloader-tool/src/drivers/uart/imx-lpuart.c

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2021, Data61, CSIRO (ABN 41 687 119 230)
+ * Copyright 2021, Breakaway Consulting Pty. Ltd.
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+/*
+ * A simple output only UART driver for the NXP i.MX Low Power UART.
+ *
+ * Technical Reference:
+ *   i.MX 8DualX/8DualXPlus/8QuadXPlus Applications Processor Reference Manual
+ *   Revision 0 (IMX8DQXPRM.pdf)
+ *   Chapter 16.13 (page 7908)
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <devices_gen.h>
+#include <drivers/common.h>
+#include <drivers/uart.h>
+
+#include <elfloader_common.h>
+
+#define STAT 0x14
+#define TRANSMIT 0x1c
+
+#define STAT_TDRE (1 << 23)
+
+#define UART_REG(mmio, x) ((volatile uint32_t *)(mmio + (x)))
+
+static int imx_lpuart_putchar(struct elfloader_device *dev, unsigned int c)
+{
+    volatile void *mmio = dev->region_bases[0];
+
+    /* Wait to be able to transmit. */
+    while (!(*UART_REG(mmio, STAT) & STAT_TDRE)) { }
+
+    *UART_REG(mmio, TRANSMIT) = c;
+
+    return 0;
+}
+
+static int imx_lpuart_init(struct elfloader_device *dev, UNUSED void *match_data)
+{
+    uart_set_out(dev);
+    return 0;
+}
+
+static const struct dtb_match_table imx_lpuart_matches[] = {
+    { .compatible = "fsl,imx8qxp-lpuart" },
+    { .compatible = NULL /* sentinel */ },
+};
+
+static const struct elfloader_uart_ops imx_lpuart_ops = {
+    .putc = &imx_lpuart_putchar,
+};
+
+static const struct elfloader_driver imx_lpuart = {
+    .match_table = imx_lpuart_matches,
+    .type = DRIVER_UART,
+    .init = &imx_lpuart_init,
+    .ops = &imx_lpuart_ops,
+};
+
+ELFLOADER_DRIVER(imx_lpuart);

elfloader-tool/src/plat/tqma8xqp1gb/platform_init.c

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2021, Data61, CSIRO (ABN 41 687 119 230)
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#include <autoconf.h>
+#include <mode/arm_generic_timer.h>
+
+/* Reset the virtual offset for the platform timer to 0 */
+void platform_init(void)
+{
+    reset_cntvoff();
+}
+
+#if CONFIG_MAX_NUM_NODES > 1
+void non_boot_init(void)
+{
+    reset_cntvoff();
+}
+#endif