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-rw-r--r--arch/mips/cavium-octeon/serial.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/serial.c b/arch/mips/cavium-octeon/serial.c
new file mode 100644
index 000000000000..8240728d485a
--- /dev/null
+++ b/arch/mips/cavium-octeon/serial.c
@@ -0,0 +1,136 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004-2007 Cavium Networks
+ */
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_reg.h>
+#include <linux/tty.h>
+
+#include <asm/time.h>
+
+#include <asm/octeon/octeon.h>
+
+#ifdef CONFIG_GDB_CONSOLE
+#define DEBUG_UART 0
+#else
+#define DEBUG_UART 1
+#endif
+
+unsigned int octeon_serial_in(struct uart_port *up, int offset)
+{
+ int rv = cvmx_read_csr((uint64_t)(up->membase + (offset << 3)));
+ if (offset == UART_IIR && (rv & 0xf) == 7) {
+ /* Busy interrupt, read the USR (39) and try again. */
+ cvmx_read_csr((uint64_t)(up->membase + (39 << 3)));
+ rv = cvmx_read_csr((uint64_t)(up->membase + (offset << 3)));
+ }
+ return rv;
+}
+
+void octeon_serial_out(struct uart_port *up, int offset, int value)
+{
+ /*
+ * If bits 6 or 7 of the OCTEON UART's LCR are set, it quits
+ * working.
+ */
+ if (offset == UART_LCR)
+ value &= 0x9f;
+ cvmx_write_csr((uint64_t)(up->membase + (offset << 3)), (u8)value);
+}
+
+/*
+ * Allocated in .bss, so it is all zeroed.
+ */
+#define OCTEON_MAX_UARTS 3
+static struct plat_serial8250_port octeon_uart8250_data[OCTEON_MAX_UARTS + 1];
+static struct platform_device octeon_uart8250_device = {
+ .name = "serial8250",
+ .id = PLAT8250_DEV_PLATFORM,
+ .dev = {
+ .platform_data = octeon_uart8250_data,
+ },
+};
+
+static void __init octeon_uart_set_common(struct plat_serial8250_port *p)
+{
+ p->flags = ASYNC_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
+ p->type = PORT_OCTEON;
+ p->iotype = UPIO_MEM;
+ p->regshift = 3; /* I/O addresses are every 8 bytes */
+ p->uartclk = mips_hpt_frequency;
+ p->serial_in = octeon_serial_in;
+ p->serial_out = octeon_serial_out;
+}
+
+static int __init octeon_serial_init(void)
+{
+ int enable_uart0;
+ int enable_uart1;
+ int enable_uart2;
+ struct plat_serial8250_port *p;
+
+#ifdef CONFIG_CAVIUM_OCTEON_2ND_KERNEL
+ /*
+ * If we are configured to run as the second of two kernels,
+ * disable uart0 and enable uart1. Uart0 is owned by the first
+ * kernel
+ */
+ enable_uart0 = 0;
+ enable_uart1 = 1;
+#else
+ /*
+ * We are configured for the first kernel. We'll enable uart0
+ * if the bootloader told us to use 0, otherwise will enable
+ * uart 1.
+ */
+ enable_uart0 = (octeon_get_boot_uart() == 0);
+ enable_uart1 = (octeon_get_boot_uart() == 1);
+#ifdef CONFIG_KGDB
+ enable_uart1 = 1;
+#endif
+#endif
+
+ /* Right now CN52XX is the only chip with a third uart */
+ enable_uart2 = OCTEON_IS_MODEL(OCTEON_CN52XX);
+
+ p = octeon_uart8250_data;
+ if (enable_uart0) {
+ /* Add a ttyS device for hardware uart 0 */
+ octeon_uart_set_common(p);
+ p->membase = (void *) CVMX_MIO_UARTX_RBR(0);
+ p->mapbase = CVMX_MIO_UARTX_RBR(0) & ((1ull << 49) - 1);
+ p->irq = OCTEON_IRQ_UART0;
+ p++;
+ }
+
+ if (enable_uart1) {
+ /* Add a ttyS device for hardware uart 1 */
+ octeon_uart_set_common(p);
+ p->membase = (void *) CVMX_MIO_UARTX_RBR(1);
+ p->mapbase = CVMX_MIO_UARTX_RBR(1) & ((1ull << 49) - 1);
+ p->irq = OCTEON_IRQ_UART1;
+ p++;
+ }
+ if (enable_uart2) {
+ /* Add a ttyS device for hardware uart 2 */
+ octeon_uart_set_common(p);
+ p->membase = (void *) CVMX_MIO_UART2_RBR;
+ p->mapbase = CVMX_MIO_UART2_RBR & ((1ull << 49) - 1);
+ p->irq = OCTEON_IRQ_UART2;
+ p++;
+ }
+
+ BUG_ON(p > &octeon_uart8250_data[OCTEON_MAX_UARTS]);
+
+ return platform_device_register(&octeon_uart8250_device);
+}
+
+device_initcall(octeon_serial_init);