From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/powerpc/platforms/embedded6xx/ls_uart.c | 142 +++++++++++++++++++++++++++ 1 file changed, 142 insertions(+) create mode 100644 arch/powerpc/platforms/embedded6xx/ls_uart.c (limited to 'arch/powerpc/platforms/embedded6xx/ls_uart.c') diff --git a/arch/powerpc/platforms/embedded6xx/ls_uart.c b/arch/powerpc/platforms/embedded6xx/ls_uart.c new file mode 100644 index 000000000..9d891bd5d --- /dev/null +++ b/arch/powerpc/platforms/embedded6xx/ls_uart.c @@ -0,0 +1,142 @@ +/* + * AVR power-management chip interface for the Buffalo Linkstation / + * Kurobox Platform. + * + * Author: 2006 (c) G. Liakhovetski + * g.liakhovetski@gmx.de + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of + * any kind, whether express or implied. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "mpc10x.h" + +static void __iomem *avr_addr; +static unsigned long avr_clock; + +static struct work_struct wd_work; + +static void wd_stop(struct work_struct *unused) +{ + const char string[] = "AAAAFFFFJJJJ>>>>VVVV>>>>ZZZZVVVVKKKK"; + int i = 0, rescue = 8; + int len = strlen(string); + + while (rescue--) { + int j; + char lsr = in_8(avr_addr + UART_LSR); + + if (lsr & (UART_LSR_THRE | UART_LSR_TEMT)) { + for (j = 0; j < 16 && i < len; j++, i++) + out_8(avr_addr + UART_TX, string[i]); + if (i == len) { + /* Read "OK" back: 4ms for the last "KKKK" + plus a couple bytes back */ + msleep(7); + printk("linkstation: disarming the AVR watchdog: "); + while (in_8(avr_addr + UART_LSR) & UART_LSR_DR) + printk("%c", in_8(avr_addr + UART_RX)); + break; + } + } + msleep(17); + } + printk("\n"); +} + +#define AVR_QUOT(clock) ((clock) + 8 * 9600) / (16 * 9600) + +void avr_uart_configure(void) +{ + unsigned char cval = UART_LCR_WLEN8; + unsigned int quot = AVR_QUOT(avr_clock); + + if (!avr_addr || !avr_clock) + return; + + out_8(avr_addr + UART_LCR, cval); /* initialise UART */ + out_8(avr_addr + UART_MCR, 0); + out_8(avr_addr + UART_IER, 0); + + cval |= UART_LCR_STOP | UART_LCR_PARITY | UART_LCR_EPAR; + + out_8(avr_addr + UART_LCR, cval); /* Set character format */ + + out_8(avr_addr + UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */ + out_8(avr_addr + UART_DLL, quot & 0xff); /* LS of divisor */ + out_8(avr_addr + UART_DLM, quot >> 8); /* MS of divisor */ + out_8(avr_addr + UART_LCR, cval); /* reset DLAB */ + out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */ +} + +void avr_uart_send(const char c) +{ + if (!avr_addr || !avr_clock) + return; + + out_8(avr_addr + UART_TX, c); + out_8(avr_addr + UART_TX, c); + out_8(avr_addr + UART_TX, c); + out_8(avr_addr + UART_TX, c); +} + +static void __init ls_uart_init(void) +{ + local_irq_disable(); + +#ifndef CONFIG_SERIAL_8250 + out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO); /* enable FIFO */ + out_8(avr_addr + UART_FCR, UART_FCR_ENABLE_FIFO | + UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); /* clear FIFOs */ + out_8(avr_addr + UART_FCR, 0); + out_8(avr_addr + UART_IER, 0); + + /* Clear up interrupts */ + (void) in_8(avr_addr + UART_LSR); + (void) in_8(avr_addr + UART_RX); + (void) in_8(avr_addr + UART_IIR); + (void) in_8(avr_addr + UART_MSR); +#endif + avr_uart_configure(); + + local_irq_enable(); +} + +static int __init ls_uarts_init(void) +{ + struct device_node *avr; + phys_addr_t phys_addr; + int len; + + avr = of_find_node_by_path("/soc10x/serial@80004500"); + if (!avr) + return -EINVAL; + + avr_clock = *(u32*)of_get_property(avr, "clock-frequency", &len); + phys_addr = ((u32*)of_get_property(avr, "reg", &len))[0]; + + if (!avr_clock || !phys_addr) + return -EINVAL; + + avr_addr = ioremap(phys_addr, 32); + if (!avr_addr) + return -EFAULT; + + ls_uart_init(); + + INIT_WORK(&wd_work, wd_stop); + schedule_work(&wd_work); + + return 0; +} + +machine_late_initcall(linkstation, ls_uarts_init); -- cgit v1.2.3-54-g00ecf