Currently, Xen supports only DT based initialization of 16550 UART.
This patch adds support for initializing 16550 UART using ACPI SPCR table.
Signed-off-by: Bhupinder Thakur <bhupinder.tha...@linaro.org>
---
CC: Andrew Cooper <andrew.coop...@citrix.com>
CC: George Dunlap <george.dun...@eu.citrix.com>
CC: Ian Jackson <ian.jack...@eu.citrix.com>
CC: Jan Beulich <jbeul...@suse.com>
CC: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
CC: Stefano Stabellini <sstabell...@kernel.org>
CC: Tim Deegan <t...@xen.org>
CC: Wei Liu <wei.l...@citrix.com>
CC: Julien Grall <julien.gr...@arm.com>
xen/drivers/char/ns16550.c | 57 +++++++++++++++++++++++++++++++++++++++++++++
xen/include/xen/8250-uart.h | 1 +
2 files changed, 58 insertions(+)
diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c
index e0f8199..b3f6d85 100644
--- a/xen/drivers/char/ns16550.c
+++ b/xen/drivers/char/ns16550.c
@@ -1538,6 +1538,63 @@ DT_DEVICE_START(ns16550, "NS16550 UART", DEVICE_SERIAL)
DT_DEVICE_END
#endif /* HAS_DEVICE_TREE */
+
+#ifdef CONFIG_ACPI
+#include <xen/acpi.h>
+
+static int __init ns16550_acpi_uart_init(const void *data)
+{
+ struct ns16550 *uart;
+ acpi_status status;
+ struct acpi_table_spcr *spcr = NULL;
+
+ status = acpi_get_table(ACPI_SIG_SPCR, 0,
+ (struct acpi_table_header **)&spcr);
+
+ if ( ACPI_FAILURE(status) )
+ {
+ printk("ns16550: Failed to get SPCR table\n");
+ return -EINVAL;
+ }
+
+ uart = &ns16550_com[0];
+
+ ns16550_init_common(uart);
+
+ uart->baud = BAUD_AUTO;
+ uart->data_bits = 8;
+ uart->parity = spcr->parity;
+ uart->stop_bits = spcr->stop_bits;
+ uart->io_base = spcr->serial_port.address;
+ uart->irq = spcr->interrupt;
+ uart->reg_width = spcr->serial_port.bit_width/8;
+ uart->reg_shift = 0;
+ uart->io_size = UART_MAX_REG<<uart->reg_shift;
+
+ irq_set_type(spcr->interrupt, spcr->interrupt_type);
+
+ uart->vuart.base_addr = uart->io_base;
+ uart->vuart.size = uart->io_size;
+ uart->vuart.data_off = UART_THR <<uart->reg_shift;
+ uart->vuart.status_off = UART_LSR<<uart->reg_shift;
+ uart->vuart.status = UART_LSR_THRE|UART_LSR_TEMT;
+
+ /* Register with generic serial driver. */
+ serial_register_uart(uart - ns16550_com, &ns16550_driver, uart);
+
+ return 0;
+}
+
+ACPI_DEVICE_START(ns16550c, "16550 COMPAT UART", DEVICE_SERIAL)
+ .class_type = ACPI_DBG2_16550_COMPATIBLE,
+ .init = ns16550_acpi_uart_init,
+ACPI_DEVICE_END
+ACPI_DEVICE_START(ns16550s, "16550 SUBSET UART", DEVICE_SERIAL)
+ .class_type = ACPI_DBG2_16550_SUBSET,
+ .init = ns16550_acpi_uart_init,
+ACPI_DEVICE_END
+
+#endif
/*
* Local variables:
* mode: C
diff --git a/xen/include/xen/8250-uart.h b/xen/include/xen/8250-uart.h
index 5c3bac3..1b3e137 100644
--- a/xen/include/xen/8250-uart.h
+++ b/xen/include/xen/8250-uart.h
@@ -35,6 +35,7 @@
#define UART_USR 0x1f /* Status register (DW) */
#define UART_DLL 0x00 /* divisor latch (ls) (DLAB=1) */
#define UART_DLM 0x01 /* divisor latch (ms) (DLAB=1) */
+#define UART_MAX_REG (UART_USR+1)
/* Interrupt Enable Register */
#define UART_IER_ERDAI 0x01 /* rx data recv'd */
--
2.7.4
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