Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Xilinx UARTLITE bootloader driver |
| 3 | * |
| 4 | * Copyright (C) 2007 Secret Lab Technologies Ltd. |
| 5 | * |
| 6 | * This file is licensed under the terms of the GNU General Public License |
| 7 | * version 2. This program is licensed "as is" without any warranty of any |
| 8 | * kind, whether express or implied. |
| 9 | */ |
| 10 | |
| 11 | #include <stdarg.h> |
| 12 | #include <stddef.h> |
| 13 | #include "types.h" |
| 14 | #include "string.h" |
| 15 | #include "stdio.h" |
| 16 | #include "io.h" |
| 17 | #include "ops.h" |
| 18 | |
Grant Likely | be1b4d34 | 2007-10-03 02:44:15 +1000 | [diff] [blame] | 19 | #define ULITE_RX 0x00 |
| 20 | #define ULITE_TX 0x04 |
| 21 | #define ULITE_STATUS 0x08 |
| 22 | #define ULITE_CONTROL 0x0c |
| 23 | |
| 24 | #define ULITE_STATUS_RXVALID 0x01 |
| 25 | #define ULITE_STATUS_TXFULL 0x08 |
| 26 | |
| 27 | #define ULITE_CONTROL_RST_RX 0x02 |
| 28 | |
Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 29 | static void * reg_base; |
| 30 | |
| 31 | static int uartlite_open(void) |
| 32 | { |
| 33 | /* Clear the RX FIFO */ |
Grant Likely | be1b4d34 | 2007-10-03 02:44:15 +1000 | [diff] [blame] | 34 | out_be32(reg_base + ULITE_CONTROL, ULITE_CONTROL_RST_RX); |
Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 35 | return 0; |
| 36 | } |
| 37 | |
| 38 | static void uartlite_putc(unsigned char c) |
| 39 | { |
Grant Likely | be1b4d34 | 2007-10-03 02:44:15 +1000 | [diff] [blame] | 40 | u32 reg = ULITE_STATUS_TXFULL; |
| 41 | while (reg & ULITE_STATUS_TXFULL) /* spin on TXFULL bit */ |
| 42 | reg = in_be32(reg_base + ULITE_STATUS); |
| 43 | out_be32(reg_base + ULITE_TX, c); |
Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 44 | } |
| 45 | |
| 46 | static unsigned char uartlite_getc(void) |
| 47 | { |
Grant Likely | 17c5c20 | 2007-10-04 15:44:54 -0600 | [diff] [blame] | 48 | u32 reg = 0; |
| 49 | while (!(reg & ULITE_STATUS_RXVALID)) /* spin waiting for RXVALID bit */ |
Grant Likely | be1b4d34 | 2007-10-03 02:44:15 +1000 | [diff] [blame] | 50 | reg = in_be32(reg_base + ULITE_STATUS); |
| 51 | return in_be32(reg_base + ULITE_RX); |
Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 52 | } |
| 53 | |
| 54 | static u8 uartlite_tstc(void) |
| 55 | { |
Grant Likely | be1b4d34 | 2007-10-03 02:44:15 +1000 | [diff] [blame] | 56 | u32 reg = in_be32(reg_base + ULITE_STATUS); |
| 57 | return reg & ULITE_STATUS_RXVALID; |
Grant Likely | 7ddc5f9 | 2007-10-02 12:15:13 +1000 | [diff] [blame] | 58 | } |
| 59 | |
| 60 | int uartlite_console_init(void *devp, struct serial_console_data *scdp) |
| 61 | { |
| 62 | int n; |
| 63 | unsigned long reg_phys; |
| 64 | |
| 65 | n = getprop(devp, "virtual-reg", ®_base, sizeof(reg_base)); |
| 66 | if (n != sizeof(reg_base)) { |
| 67 | if (!dt_xlate_reg(devp, 0, ®_phys, NULL)) |
| 68 | return -1; |
| 69 | |
| 70 | reg_base = (void *)reg_phys; |
| 71 | } |
| 72 | |
| 73 | scdp->open = uartlite_open; |
| 74 | scdp->putc = uartlite_putc; |
| 75 | scdp->getc = uartlite_getc; |
| 76 | scdp->tstc = uartlite_tstc; |
| 77 | scdp->close = NULL; |
| 78 | return 0; |
| 79 | } |