[PATCH v2 21/41] arm : acpi Initialize serial port from ACPI SPCR table

[Parth Dixit <parth.dixit@linaro.org>]

Parse ACPI SPCR (Serial Port Console Redirection table) table and
initialize the serial port pl011.

Signed-off-by: Naresh Bhat <naresh.bhat@linaro.org>
Signed-off-by: Parth Dixit <parth.dixit@linaro.org>
---
 xen/drivers/char/pl011.c  | 49 +++++++++++++++++++++++++++++++++++++++++++++++
 xen/include/acpi/actbl2.h |  5 +++++
 2 files changed, 54 insertions(+)

diff --git a/xen/drivers/char/pl011.c b/xen/drivers/char/pl011.c
index f0c3daf..bc34555 100644
--- a/xen/drivers/char/pl011.c
+++ b/xen/drivers/char/pl011.c
@@ -27,6 +27,7 @@
 #include <asm/device.h>
 #include <xen/mm.h>
 #include <xen/vmap.h>
+#include <xen/acpi.h>
 #include <asm/pl011-uart.h>
 #include <asm/io.h>
 
@@ -307,6 +308,54 @@ DT_DEVICE_START(pl011, "PL011 UART", DEVICE_SERIAL)
         .init = dt_pl011_uart_init,
 DT_DEVICE_END
 
+#ifdef CONFIG_ACPI
+static int __init acpi_pl011_uart_init(const void *data)
+{
+    struct pl011 *uart;
+    acpi_status status;
+    struct acpi_table_spcr *spcr=NULL;
+    int res;
+
+    status = acpi_get_table(ACPI_SIG_SPCR, 0,
+            (struct acpi_table_header **)&spcr);
+
+    if ( ACPI_FAILURE(status) )
+    {
+        printk("\nFailed to get SPCR table \n");
+        return 1;
+    }
+
+    uart = &pl011_com;
+
+    if ( spcr->interrupt < 0 )
+    {
+        printk("pl011: Unable to retrieve the IRQ\n");
+        return -EINVAL;
+    }
+
+    uart->irq = spcr->interrupt;
+    /* trigger/polarity information is not available in spcr */
+    set_irq_type(uart->irq, ACPI_IRQ_TYPE_EDGE_BOTH);
+
+    res = pl011_uart_init(uart, spcr->serial_port.address, PAGE_SIZE);
+    if ( res < 0 )
+    {
+        printk("pl011: Unable to initialize\n");
+        return res;
+    }
+
+    /* Register with generic serial driver. */
+    serial_register_uart(SERHND_UART, &pl011_driver, uart);
+
+    return 0;
+}
+
+ACPI_DEVICE_START(apl011, "PL011 UART", DEVICE_SERIAL)
+        .class_type = ACPI_SPCR_TYPE_PL011,
+        .init = acpi_pl011_uart_init,
+ACPI_DEVICE_END
+#endif
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/acpi/actbl2.h b/xen/include/acpi/actbl2.h
index 87bc6b3..25be429 100644
--- a/xen/include/acpi/actbl2.h
+++ b/xen/include/acpi/actbl2.h
@@ -815,6 +815,11 @@ struct acpi_table_spcr {
 
 #define ACPI_SPCR_DO_NOT_DISABLE    (1)
 
+/* UART Interface type */
+#define ACPI_SPCR_TYPE_16550 0
+#define ACPI_SPCR_TYPE_16550_SUB 1
+#define ACPI_SPCR_TYPE_PL011 3
+
 /*******************************************************************************
  *
  * SPMI - Server Platform Management Interface table
-- 
1.9.1