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authorYuval Adam <_@yuv.al>2017-08-30 08:25:59 +0000
committerYuval Adam <_@yuv.al>2017-08-30 08:25:59 +0000
commit8e4bff4cab0ddac6060645b0715210484d02ff40 (patch)
tree3a5c3024371a04692a3a6d9974d001cdff8ebf84 /arch/mips/cavium-octeon/serial.c
Initial file dump from open source releaseHEADmaster
Diffstat (limited to 'arch/mips/cavium-octeon/serial.c')
-rw-r--r--arch/mips/cavium-octeon/serial.c109
1 files changed, 109 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/serial.c b/arch/mips/cavium-octeon/serial.c
new file mode 100644
index 00000000..f393f65f
--- /dev/null
+++ b/arch/mips/cavium-octeon/serial.c
@@ -0,0 +1,109 @@
+/*
+ * 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 <linux/irq.h>
+
+#include <asm/time.h>
+
+#include <asm/octeon/octeon.h>
+
+#define DEBUG_UART 1
+
+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);
+}
+
+static int octeon_serial_probe(struct platform_device *pdev)
+{
+ int irq, res;
+ struct resource *res_mem;
+ struct uart_8250_port up;
+
+ /* All adaptors have an irq. */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ memset(&up, 0, sizeof(up));
+
+ up.port.flags = ASYNC_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
+ up.port.type = PORT_OCTEON;
+ up.port.iotype = UPIO_MEM;
+ up.port.regshift = 3;
+ up.port.dev = &pdev->dev;
+
+ if (octeon_is_simulation())
+ /* Make simulator output fast*/
+ up.port.uartclk = 115200 * 16;
+ else
+ up.port.uartclk = octeon_get_io_clock_rate();
+
+ up.port.serial_in = octeon_serial_in;
+ up.port.serial_out = octeon_serial_out;
+ up.port.irq = irq;
+
+ res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res_mem == NULL) {
+ dev_err(&pdev->dev, "found no memory resource\n");
+ return -ENXIO;
+ }
+ up.port.mapbase = res_mem->start;
+ up.port.membase = ioremap(res_mem->start, resource_size(res_mem));
+
+ res = serial8250_register_8250_port(&up);
+
+ return res >= 0 ? 0 : res;
+}
+
+static struct of_device_id octeon_serial_match[] = {
+ {
+ .compatible = "cavium,octeon-3860-uart",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, octeon_serial_match);
+
+static struct platform_driver octeon_serial_driver = {
+ .probe = octeon_serial_probe,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "octeon_serial",
+ .of_match_table = octeon_serial_match,
+ },
+};
+
+static int __init octeon_serial_init(void)
+{
+ return platform_driver_register(&octeon_serial_driver);
+}
+late_initcall(octeon_serial_init);