xref: /openbmc/u-boot/arch/arm/mach-kirkwood/mpp.c (revision ed09a554)
1 /*
2  * arch/arm/mach-kirkwood/mpp.c
3  *
4  * MPP functions for Marvell Kirkwood SoCs
5  * Referenced from Linux kernel source
6  *
7  * This file is licensed under the terms of the GNU General Public
8  * License version 2.  This program is licensed "as is" without any
9  * warranty of any kind, whether express or implied.
10  */
11 
12 #include <common.h>
13 #include <asm/io.h>
14 #include <asm/arch/cpu.h>
15 #include <asm/arch/soc.h>
16 #include <asm/arch/mpp.h>
17 
18 static u32 kirkwood_variant(void)
19 {
20 	switch (readl(KW_REG_DEVICE_ID) & 0x03) {
21 	case 1:
22 		return MPP_F6192_MASK;
23 	case 2:
24 		return MPP_F6281_MASK;
25 	default:
26 		debug("MPP setup: unknown kirkwood variant\n");
27 		return 0;
28 	}
29 }
30 
31 #define MPP_CTRL(i)	(KW_MPP_BASE + (i* 4))
32 #define MPP_NR_REGS	(1 + MPP_MAX/8)
33 
34 void kirkwood_mpp_conf(const u32 *mpp_list, u32 *mpp_save)
35 {
36 	u32 mpp_ctrl[MPP_NR_REGS];
37 	unsigned int variant_mask;
38 	int i;
39 
40 	variant_mask = kirkwood_variant();
41 	if (!variant_mask)
42 		return;
43 
44 	debug( "initial MPP regs:");
45 	for (i = 0; i < MPP_NR_REGS; i++) {
46 		mpp_ctrl[i] = readl(MPP_CTRL(i));
47 		debug(" %08x", mpp_ctrl[i]);
48 	}
49 	debug("\n");
50 
51 
52 	while (*mpp_list) {
53 		unsigned int num = MPP_NUM(*mpp_list);
54 		unsigned int sel = MPP_SEL(*mpp_list);
55 		unsigned int sel_save;
56 		int shift;
57 
58 		if (num > MPP_MAX) {
59 			debug("kirkwood_mpp_conf: invalid MPP "
60 					"number (%u)\n", num);
61 			continue;
62 		}
63 		if (!(*mpp_list & variant_mask)) {
64 			debug("kirkwood_mpp_conf: requested MPP%u config "
65 				"unavailable on this hardware\n", num);
66 			continue;
67 		}
68 
69 		shift = (num & 7) << 2;
70 
71 		if (mpp_save) {
72 			sel_save = (mpp_ctrl[num / 8] >> shift) & 0xf;
73 			*mpp_save = num | (sel_save << 8) | variant_mask;
74 			mpp_save++;
75 		}
76 
77 		mpp_ctrl[num / 8] &= ~(0xf << shift);
78 		mpp_ctrl[num / 8] |= sel << shift;
79 
80 		mpp_list++;
81 	}
82 
83 	debug("  final MPP regs:");
84 	for (i = 0; i < MPP_NR_REGS; i++) {
85 		writel(mpp_ctrl[i], MPP_CTRL(i));
86 		debug(" %08x", mpp_ctrl[i]);
87 	}
88 	debug("\n");
89 
90 }
91