diff options
author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
---|---|---|
committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /arch/arm/mach-omap2/prm2xxx_3xxx.c | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'arch/arm/mach-omap2/prm2xxx_3xxx.c')
-rw-r--r-- | arch/arm/mach-omap2/prm2xxx_3xxx.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/prm2xxx_3xxx.c b/arch/arm/mach-omap2/prm2xxx_3xxx.c new file mode 100644 index 00000000..051213fb --- /dev/null +++ b/arch/arm/mach-omap2/prm2xxx_3xxx.c @@ -0,0 +1,158 @@ +/* + * OMAP2/3 PRM module functions + * + * Copyright (C) 2010 Texas Instruments, Inc. + * Copyright (C) 2010 Nokia Corporation + * BenoƮt Cousson + * Paul Walmsley + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/io.h> + +#include <plat/common.h> +#include <plat/cpu.h> +#include <plat/prcm.h> + +#include "prm2xxx_3xxx.h" +#include "cm2xxx_3xxx.h" +#include "prm-regbits-24xx.h" +#include "prm-regbits-34xx.h" + +u32 omap2_prm_read_mod_reg(s16 module, u16 idx) +{ + return __raw_readl(prm_base + module + idx); +} + +void omap2_prm_write_mod_reg(u32 val, s16 module, u16 idx) +{ + __raw_writel(val, prm_base + module + idx); +} + +/* Read-modify-write a register in a PRM module. Caller must lock */ +u32 omap2_prm_rmw_mod_reg_bits(u32 mask, u32 bits, s16 module, s16 idx) +{ + u32 v; + + v = omap2_prm_read_mod_reg(module, idx); + v &= ~mask; + v |= bits; + omap2_prm_write_mod_reg(v, module, idx); + + return v; +} + +/* Read a PRM register, AND it, and shift the result down to bit 0 */ +u32 omap2_prm_read_mod_bits_shift(s16 domain, s16 idx, u32 mask) +{ + u32 v; + + v = omap2_prm_read_mod_reg(domain, idx); + v &= mask; + v >>= __ffs(mask); + + return v; +} + +u32 omap2_prm_set_mod_reg_bits(u32 bits, s16 module, s16 idx) +{ + return omap2_prm_rmw_mod_reg_bits(bits, bits, module, idx); +} + +u32 omap2_prm_clear_mod_reg_bits(u32 bits, s16 module, s16 idx) +{ + return omap2_prm_rmw_mod_reg_bits(bits, 0x0, module, idx); +} + + +/** + * omap2_prm_is_hardreset_asserted - read the HW reset line state of + * submodules contained in the hwmod module + * @prm_mod: PRM submodule base (e.g. CORE_MOD) + * @shift: register bit shift corresponding to the reset line to check + * + * Returns 1 if the (sub)module hardreset line is currently asserted, + * 0 if the (sub)module hardreset line is not currently asserted, or + * -EINVAL if called while running on a non-OMAP2/3 chip. + */ +int omap2_prm_is_hardreset_asserted(s16 prm_mod, u8 shift) +{ + if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) + return -EINVAL; + + return omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, + (1 << shift)); +} + +/** + * omap2_prm_assert_hardreset - assert the HW reset line of a submodule + * @prm_mod: PRM submodule base (e.g. CORE_MOD) + * @shift: register bit shift corresponding to the reset line to assert + * + * Some IPs like dsp or iva contain processors that require an HW + * reset line to be asserted / deasserted in order to fully enable the + * IP. These modules may have multiple hard-reset lines that reset + * different 'submodules' inside the IP block. This function will + * place the submodule into reset. Returns 0 upon success or -EINVAL + * upon an argument error. + */ +int omap2_prm_assert_hardreset(s16 prm_mod, u8 shift) +{ + u32 mask; + + if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) + return -EINVAL; + + mask = 1 << shift; + omap2_prm_rmw_mod_reg_bits(mask, mask, prm_mod, OMAP2_RM_RSTCTRL); + + return 0; +} + +/** + * omap2_prm_deassert_hardreset - deassert a submodule hardreset line and wait + * @prm_mod: PRM submodule base (e.g. CORE_MOD) + * @rst_shift: register bit shift corresponding to the reset line to deassert + * @st_shift: register bit shift for the status of the deasserted submodule + * + * Some IPs like dsp or iva contain processors that require an HW + * reset line to be asserted / deasserted in order to fully enable the + * IP. These modules may have multiple hard-reset lines that reset + * different 'submodules' inside the IP block. This function will + * take the submodule out of reset and wait until the PRCM indicates + * that the reset has completed before returning. Returns 0 upon success or + * -EINVAL upon an argument error, -EEXIST if the submodule was already out + * of reset, or -EBUSY if the submodule did not exit reset promptly. + */ +int omap2_prm_deassert_hardreset(s16 prm_mod, u8 rst_shift, u8 st_shift) +{ + u32 rst, st; + int c; + + if (!(cpu_is_omap24xx() || cpu_is_omap34xx())) + return -EINVAL; + + rst = 1 << rst_shift; + st = 1 << st_shift; + + /* Check the current status to avoid de-asserting the line twice */ + if (omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTCTRL, rst) == 0) + return -EEXIST; + + /* Clear the reset status by writing 1 to the status bit */ + omap2_prm_rmw_mod_reg_bits(0xffffffff, st, prm_mod, OMAP2_RM_RSTST); + /* de-assert the reset control line */ + omap2_prm_rmw_mod_reg_bits(rst, 0, prm_mod, OMAP2_RM_RSTCTRL); + /* wait the status to be set */ + omap_test_timeout(omap2_prm_read_mod_bits_shift(prm_mod, OMAP2_RM_RSTST, + st), + MAX_MODULE_HARDRESET_WAIT, c); + + return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0; +} |