1cf21405fSPaul Walmsley /* 2cf21405fSPaul Walmsley * OMAP2/3 PRM module functions 3cf21405fSPaul Walmsley * 4cf21405fSPaul Walmsley * Copyright (C) 2010 Texas Instruments, Inc. 5cf21405fSPaul Walmsley * Copyright (C) 2010 Nokia Corporation 6cf21405fSPaul Walmsley * Benoît Cousson 7cf21405fSPaul Walmsley * Paul Walmsley 8cf21405fSPaul Walmsley * 9cf21405fSPaul Walmsley * This program is free software; you can redistribute it and/or modify 10cf21405fSPaul Walmsley * it under the terms of the GNU General Public License version 2 as 11cf21405fSPaul Walmsley * published by the Free Software Foundation. 12cf21405fSPaul Walmsley */ 13cf21405fSPaul Walmsley 14cf21405fSPaul Walmsley #include <linux/kernel.h> 15cf21405fSPaul Walmsley #include <linux/delay.h> 16cf21405fSPaul Walmsley #include <linux/errno.h> 17cf21405fSPaul Walmsley #include <linux/err.h> 18cf21405fSPaul Walmsley 19cf21405fSPaul Walmsley #include <plat/common.h> 20cf21405fSPaul Walmsley #include <plat/cpu.h> 21cf21405fSPaul Walmsley #include <plat/prcm.h> 22cf21405fSPaul Walmsley 23cf21405fSPaul Walmsley #include "prm.h" 24cf21405fSPaul Walmsley #include "prm-regbits-24xx.h" 25cf21405fSPaul Walmsley #include "prm-regbits-34xx.h" 26cf21405fSPaul Walmsley 27cf21405fSPaul Walmsley /** 28cf21405fSPaul Walmsley * omap2_prm_is_hardreset_asserted - read the HW reset line state of 29cf21405fSPaul Walmsley * submodules contained in the hwmod module 30cf21405fSPaul Walmsley * @prm_mod: PRM submodule base (e.g. CORE_MOD) 31cf21405fSPaul Walmsley * @shift: register bit shift corresponding to the reset line to check 32cf21405fSPaul Walmsley * 33cf21405fSPaul Walmsley * Returns 1 if the (sub)module hardreset line is currently asserted, 34cf21405fSPaul Walmsley * 0 if the (sub)module hardreset line is not currently asserted, or 35cf21405fSPaul Walmsley * -EINVAL if called while running on a non-OMAP2/3 chip. 36cf21405fSPaul Walmsley */ 37cf21405fSPaul Walmsley int omap2_prm_is_hardreset_asserted(s16 prm_mod, u8 shift) 38cf21405fSPaul Walmsley { 39cf21405fSPaul Walmsley if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) 40cf21405fSPaul Walmsley return -EINVAL; 41cf21405fSPaul Walmsley 42cf21405fSPaul Walmsley return prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, 43cf21405fSPaul Walmsley (1 << shift)); 44cf21405fSPaul Walmsley } 45cf21405fSPaul Walmsley 46cf21405fSPaul Walmsley /** 47cf21405fSPaul Walmsley * omap2_prm_assert_hardreset - assert the HW reset line of a submodule 48cf21405fSPaul Walmsley * @prm_mod: PRM submodule base (e.g. CORE_MOD) 49cf21405fSPaul Walmsley * @shift: register bit shift corresponding to the reset line to assert 50cf21405fSPaul Walmsley * 51cf21405fSPaul Walmsley * Some IPs like dsp or iva contain processors that require an HW 52cf21405fSPaul Walmsley * reset line to be asserted / deasserted in order to fully enable the 53cf21405fSPaul Walmsley * IP. These modules may have multiple hard-reset lines that reset 54cf21405fSPaul Walmsley * different 'submodules' inside the IP block. This function will 55cf21405fSPaul Walmsley * place the submodule into reset. Returns 0 upon success or -EINVAL 56cf21405fSPaul Walmsley * upon an argument error. 57cf21405fSPaul Walmsley */ 58cf21405fSPaul Walmsley int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift) 59cf21405fSPaul Walmsley { 60cf21405fSPaul Walmsley u32 mask; 61cf21405fSPaul Walmsley 62cf21405fSPaul Walmsley if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) 63cf21405fSPaul Walmsley return -EINVAL; 64cf21405fSPaul Walmsley 65cf21405fSPaul Walmsley mask = 1 << shift; 66cf21405fSPaul Walmsley prm_rmw_mod_reg_bits(mask, mask, prm_mod, OMAP2_RM_RSTCTRL); 67cf21405fSPaul Walmsley 68cf21405fSPaul Walmsley return 0; 69cf21405fSPaul Walmsley } 70cf21405fSPaul Walmsley 71cf21405fSPaul Walmsley /** 72cf21405fSPaul Walmsley * omap2_prm_deassert_hardreset - deassert a submodule hardreset line and wait 73cf21405fSPaul Walmsley * @prm_mod: PRM submodule base (e.g. CORE_MOD) 74cf21405fSPaul Walmsley * @shift: register bit shift corresponding to the reset line to deassert 75cf21405fSPaul Walmsley * 76cf21405fSPaul Walmsley * Some IPs like dsp or iva contain processors that require an HW 77cf21405fSPaul Walmsley * reset line to be asserted / deasserted in order to fully enable the 78cf21405fSPaul Walmsley * IP. These modules may have multiple hard-reset lines that reset 79cf21405fSPaul Walmsley * different 'submodules' inside the IP block. This function will 80cf21405fSPaul Walmsley * take the submodule out of reset and wait until the PRCM indicates 81cf21405fSPaul Walmsley * that the reset has completed before returning. Returns 0 upon success or 82cf21405fSPaul Walmsley * -EINVAL upon an argument error, -EEXIST if the submodule was already out 83cf21405fSPaul Walmsley * of reset, or -EBUSY if the submodule did not exit reset promptly. 84cf21405fSPaul Walmsley */ 85cf21405fSPaul Walmsley int omap2_prm_deassert_hardreset(s16 prm_mod, u8 shift) 86cf21405fSPaul Walmsley { 87cf21405fSPaul Walmsley u32 mask; 88cf21405fSPaul Walmsley int c; 89cf21405fSPaul Walmsley 90cf21405fSPaul Walmsley if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) 91cf21405fSPaul Walmsley return -EINVAL; 92cf21405fSPaul Walmsley 93cf21405fSPaul Walmsley mask = 1 << shift; 94cf21405fSPaul Walmsley 95cf21405fSPaul Walmsley /* Check the current status to avoid de-asserting the line twice */ 96cf21405fSPaul Walmsley if (prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, mask) == 0) 97cf21405fSPaul Walmsley return -EEXIST; 98cf21405fSPaul Walmsley 99cf21405fSPaul Walmsley /* Clear the reset status by writing 1 to the status bit */ 100cf21405fSPaul Walmsley prm_rmw_mod_reg_bits(0xffffffff, mask, prm_mod, OMAP2_RM_RSTST); 101cf21405fSPaul Walmsley /* de-assert the reset control line */ 102cf21405fSPaul Walmsley prm_rmw_mod_reg_bits(mask, 0, prm_mod, OMAP2_RM_RSTCTRL); 103cf21405fSPaul Walmsley /* wait the status to be set */ 104cf21405fSPaul Walmsley omap_test_timeout(prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTST, 105cf21405fSPaul Walmsley mask), 106cf21405fSPaul Walmsley MAX_MODULE_HARDRESET_WAIT, c); 107cf21405fSPaul Walmsley 108cf21405fSPaul Walmsley return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0; 109cf21405fSPaul Walmsley } 110cf21405fSPaul Walmsley 111