diff options
Diffstat (limited to 'arch/powerpc/boot/uartlite.c')
-rw-r--r-- | arch/powerpc/boot/uartlite.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/powerpc/boot/uartlite.c b/arch/powerpc/boot/uartlite.c new file mode 100644 index 000000000000..46bed69b4169 --- /dev/null +++ b/arch/powerpc/boot/uartlite.c | |||
@@ -0,0 +1,79 @@ | |||
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 | |||
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 | |||
29 | static void * reg_base; | ||
30 | |||
31 | static int uartlite_open(void) | ||
32 | { | ||
33 | /* Clear the RX FIFO */ | ||
34 | out_be32(reg_base + ULITE_CONTROL, ULITE_CONTROL_RST_RX); | ||
35 | return 0; | ||
36 | } | ||
37 | |||
38 | static void uartlite_putc(unsigned char c) | ||
39 | { | ||
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); | ||
44 | } | ||
45 | |||
46 | static unsigned char uartlite_getc(void) | ||
47 | { | ||
48 | u32 reg = 0; | ||
49 | while (!(reg & ULITE_STATUS_RXVALID)) /* spin waiting for RXVALID bit */ | ||
50 | reg = in_be32(reg_base + ULITE_STATUS); | ||
51 | return in_be32(reg_base + ULITE_RX); | ||
52 | } | ||
53 | |||
54 | static u8 uartlite_tstc(void) | ||
55 | { | ||
56 | u32 reg = in_be32(reg_base + ULITE_STATUS); | ||
57 | return reg & ULITE_STATUS_RXVALID; | ||
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 | } | ||