xref: /openbmc/u-boot/arch/arm/mach-omap2/omap5/abb.c (revision e8645527)
1 /*
2  * Adaptive Body Bias programming sequence for OMAP5 family
3  *
4  * (C) Copyright 2013
5  * Texas Instruments, <www.ti.com>
6  *
7  * Andrii Tseglytskyi <andrii.tseglytskyi@ti.com>
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 
12 #include <common.h>
13 #include <asm/omap_common.h>
14 #include <asm/io.h>
15 
16 /*
17  * Setup LDOVBB for OMAP5.
18  * On OMAP5+ some ABB settings are fused. They are handled
19  * in the following way:
20  *
21  * 1. corresponding EFUSE register contains ABB enable bit
22  *    and VSET value
23  * 2. If ABB enable bit is set to 1, than ABB should be
24  *    enabled, otherwise ABB should be disabled
25  * 3. If ABB is enabled, than VSET value should be copied
26  *    to corresponding MUX control register
27  */
28 s8 abb_setup_ldovbb(u32 fuse, u32 ldovbb)
29 {
30 	u32 vset;
31 	u32 fuse_enable_mask = OMAP5_PROD_ABB_FUSE_ENABLE_MASK;
32 	u32 fuse_vset_mask = OMAP5_PROD_ABB_FUSE_VSET_MASK;
33 
34 	if (!is_omap54xx()) {
35 		/* DRA7 */
36 		fuse_enable_mask = DRA7_ABB_FUSE_ENABLE_MASK;
37 		fuse_vset_mask = DRA7_ABB_FUSE_VSET_MASK;
38 	}
39 	/*
40 	 * ABB parameters must be properly fused
41 	 * otherwise ABB should be disabled
42 	 */
43 	vset = readl(fuse);
44 	if (!(vset & fuse_enable_mask))
45 		return -1;
46 
47 	/* prepare VSET value for LDOVBB mux register */
48 	vset &= fuse_vset_mask;
49 	vset >>= ffs(fuse_vset_mask) - 1;
50 	vset <<= ffs(OMAP5_ABB_LDOVBBMPU_VSET_OUT_MASK) - 1;
51 	vset |= OMAP5_ABB_LDOVBBMPU_MUX_CTRL_MASK;
52 
53 	/* setup LDOVBB using fused value */
54 	clrsetbits_le32(ldovbb,  OMAP5_ABB_LDOVBBMPU_VSET_OUT_MASK, vset);
55 
56 	return 0;
57 }
58