diff options
Diffstat (limited to 'arch/arm/mach-omap2/prm33xx.c')
| -rw-r--r-- | arch/arm/mach-omap2/prm33xx.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/prm33xx.c b/arch/arm/mach-omap2/prm33xx.c new file mode 100644 index 000000000..9144cc047 --- /dev/null +++ b/arch/arm/mach-omap2/prm33xx.c @@ -0,0 +1,409 @@ +/* + * AM33XX PRM functions + * + * Copyright (C) 2011-2012 Texas Instruments Incorporated - https://www.ti.com/ + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/io.h> + +#include "powerdomain.h" +#include "prm33xx.h" +#include "prm-regbits-33xx.h" + +#define AM33XX_PRM_RSTCTRL_OFFSET 0x0000 + +#define AM33XX_RST_GLOBAL_WARM_SW_MASK (1 << 0) + +/* Read a register in a PRM instance */ +static u32 am33xx_prm_read_reg(s16 inst, u16 idx) +{ + return readl_relaxed(prm_base.va + inst + idx); +} + +/* Write into a register in a PRM instance */ +static void am33xx_prm_write_reg(u32 val, s16 inst, u16 idx) +{ + writel_relaxed(val, prm_base.va + inst + idx); +} + +/* Read-modify-write a register in PRM. Caller must lock */ +static u32 am33xx_prm_rmw_reg_bits(u32 mask, u32 bits, s16 inst, s16 idx) +{ + u32 v; + + v = am33xx_prm_read_reg(inst, idx); + v &= ~mask; + v |= bits; + am33xx_prm_write_reg(v, inst, idx); + + return v; +} + +/** + * am33xx_prm_is_hardreset_asserted - read the HW reset line state of + * submodules contained in the hwmod module + * @shift: register bit shift corresponding to the reset line to check + * @part: PRM partition, ignored for AM33xx + * @inst: CM instance register offset (*_INST macro) + * @rstctrl_offs: RM_RSTCTRL register address offset for this module + * + * Returns 1 if the (sub)module hardreset line is currently asserted, + * 0 if the (sub)module hardreset line is not currently asserted, or + * -EINVAL upon parameter error. + */ +static int am33xx_prm_is_hardreset_asserted(u8 shift, u8 part, s16 inst, + u16 rstctrl_offs) +{ + u32 v; + + v = am33xx_prm_read_reg(inst, rstctrl_offs); + v &= 1 << shift; + v >>= shift; + + return v; +} + +/** + * am33xx_prm_assert_hardreset - assert the HW reset line of a submodule + * @shift: register bit shift corresponding to the reset line to assert + * @part: CM partition, ignored for AM33xx + * @inst: CM instance register offset (*_INST macro) + * @rstctrl_reg: RM_RSTCTRL register address for this module + * + * Some IPs like dsp, ipu 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. + */ +static int am33xx_prm_assert_hardreset(u8 shift, u8 part, s16 inst, + u16 rstctrl_offs) +{ + u32 mask = 1 << shift; + + am33xx_prm_rmw_reg_bits(mask, mask, inst, rstctrl_offs); + + return 0; +} + +/** + * am33xx_prm_deassert_hardreset - deassert a submodule hardreset line and + * wait + * @shift: register bit shift corresponding to the reset line to deassert + * @st_shift: reset status register bit shift corresponding to the reset line + * @part: PRM partition, not used for AM33xx + * @inst: CM instance register offset (*_INST macro) + * @rstctrl_reg: RM_RSTCTRL register address for this module + * @rstst_reg: RM_RSTST register address for this module + * + * Some IPs like dsp, ipu 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. + */ +static int am33xx_prm_deassert_hardreset(u8 shift, u8 st_shift, u8 part, + s16 inst, u16 rstctrl_offs, + u16 rstst_offs) +{ + int c; + u32 mask = 1 << st_shift; + + /* Check the current status to avoid de-asserting the line twice */ + if (am33xx_prm_is_hardreset_asserted(shift, 0, inst, rstctrl_offs) == 0) + return -EEXIST; + + /* Clear the reset status by writing 1 to the status bit */ + am33xx_prm_rmw_reg_bits(0xffffffff, mask, inst, rstst_offs); + + /* de-assert the reset control line */ + mask = 1 << shift; + + am33xx_prm_rmw_reg_bits(mask, 0, inst, rstctrl_offs); + + /* wait the status to be set */ + omap_test_timeout(am33xx_prm_is_hardreset_asserted(st_shift, 0, inst, + rstst_offs), + MAX_MODULE_HARDRESET_WAIT, c); + + return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0; +} + +static int am33xx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst) +{ + am33xx_prm_rmw_reg_bits(OMAP_POWERSTATE_MASK, + (pwrst << OMAP_POWERSTATE_SHIFT), + pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + return 0; +} + +static int am33xx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm) +{ + u32 v; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + v &= OMAP_POWERSTATE_MASK; + v >>= OMAP_POWERSTATE_SHIFT; + + return v; +} + +static int am33xx_pwrdm_read_pwrst(struct powerdomain *pwrdm) +{ + u32 v; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs); + v &= OMAP_POWERSTATEST_MASK; + v >>= OMAP_POWERSTATEST_SHIFT; + + return v; +} + +static int am33xx_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm) +{ + am33xx_prm_rmw_reg_bits(AM33XX_LOWPOWERSTATECHANGE_MASK, + (1 << AM33XX_LOWPOWERSTATECHANGE_SHIFT), + pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + return 0; +} + +static int am33xx_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm) +{ + am33xx_prm_rmw_reg_bits(AM33XX_LASTPOWERSTATEENTERED_MASK, + AM33XX_LASTPOWERSTATEENTERED_MASK, + pwrdm->prcm_offs, pwrdm->pwrstst_offs); + return 0; +} + +static int am33xx_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst) +{ + u32 m; + + m = pwrdm->logicretstate_mask; + if (!m) + return -EINVAL; + + am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)), + pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + + return 0; +} + +static int am33xx_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm) +{ + u32 v; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs); + v &= AM33XX_LOGICSTATEST_MASK; + v >>= AM33XX_LOGICSTATEST_SHIFT; + + return v; +} + +static int am33xx_pwrdm_read_logic_retst(struct powerdomain *pwrdm) +{ + u32 v, m; + + m = pwrdm->logicretstate_mask; + if (!m) + return -EINVAL; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + v &= m; + v >>= __ffs(m); + + return v; +} + +static int am33xx_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank, + u8 pwrst) +{ + u32 m; + + m = pwrdm->mem_on_mask[bank]; + if (!m) + return -EINVAL; + + am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)), + pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + + return 0; +} + +static int am33xx_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank, + u8 pwrst) +{ + u32 m; + + m = pwrdm->mem_ret_mask[bank]; + if (!m) + return -EINVAL; + + am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)), + pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + + return 0; +} + +static int am33xx_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank) +{ + u32 m, v; + + m = pwrdm->mem_pwrst_mask[bank]; + if (!m) + return -EINVAL; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs); + v &= m; + v >>= __ffs(m); + + return v; +} + +static int am33xx_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank) +{ + u32 m, v; + + m = pwrdm->mem_retst_mask[bank]; + if (!m) + return -EINVAL; + + v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs); + v &= m; + v >>= __ffs(m); + + return v; +} + +static int am33xx_pwrdm_wait_transition(struct powerdomain *pwrdm) +{ + u32 c = 0; + + /* + * REVISIT: pwrdm_wait_transition() may be better implemented + * via a callback and a periodic timer check -- how long do we expect + * powerdomain transitions to take? + */ + + /* XXX Is this udelay() value meaningful? */ + while ((am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs) + & OMAP_INTRANSITION_MASK) && + (c++ < PWRDM_TRANSITION_BAILOUT)) + udelay(1); + + if (c > PWRDM_TRANSITION_BAILOUT) { + pr_err("powerdomain: %s: waited too long to complete transition\n", + pwrdm->name); + return -EAGAIN; + } + + pr_debug("powerdomain: completed transition in %d loops\n", c); + + return 0; +} + +static int am33xx_check_vcvp(void) +{ + /* No VC/VP on am33xx devices */ + return 0; +} + +/** + * am33xx_prm_global_warm_sw_reset - reboot the device via warm reset + * + * Immediately reboots the device through warm reset. + */ +static void am33xx_prm_global_warm_sw_reset(void) +{ + am33xx_prm_rmw_reg_bits(AM33XX_RST_GLOBAL_WARM_SW_MASK, + AM33XX_RST_GLOBAL_WARM_SW_MASK, + AM33XX_PRM_DEVICE_MOD, + AM33XX_PRM_RSTCTRL_OFFSET); + + /* OCP barrier */ + (void)am33xx_prm_read_reg(AM33XX_PRM_DEVICE_MOD, + AM33XX_PRM_RSTCTRL_OFFSET); +} + +static void am33xx_pwrdm_save_context(struct powerdomain *pwrdm) +{ + pwrdm->context = am33xx_prm_read_reg(pwrdm->prcm_offs, + pwrdm->pwrstctrl_offs); + /* + * Do not save LOWPOWERSTATECHANGE, writing a 1 indicates a request, + * reading back a 1 indicates a request in progress. + */ + pwrdm->context &= ~AM33XX_LOWPOWERSTATECHANGE_MASK; +} + +static void am33xx_pwrdm_restore_context(struct powerdomain *pwrdm) +{ + int st, ctrl; + + st = am33xx_prm_read_reg(pwrdm->prcm_offs, + pwrdm->pwrstst_offs); + + am33xx_prm_write_reg(pwrdm->context, pwrdm->prcm_offs, + pwrdm->pwrstctrl_offs); + + /* Make sure we only wait for a transition if there is one */ + st &= OMAP_POWERSTATEST_MASK; + ctrl = OMAP_POWERSTATEST_MASK & pwrdm->context; + + if (st != ctrl) + am33xx_pwrdm_wait_transition(pwrdm); +} + +struct pwrdm_ops am33xx_pwrdm_operations = { + .pwrdm_set_next_pwrst = am33xx_pwrdm_set_next_pwrst, + .pwrdm_read_next_pwrst = am33xx_pwrdm_read_next_pwrst, + .pwrdm_read_pwrst = am33xx_pwrdm_read_pwrst, + .pwrdm_set_logic_retst = am33xx_pwrdm_set_logic_retst, + .pwrdm_read_logic_pwrst = am33xx_pwrdm_read_logic_pwrst, + .pwrdm_read_logic_retst = am33xx_pwrdm_read_logic_retst, + .pwrdm_clear_all_prev_pwrst = am33xx_pwrdm_clear_all_prev_pwrst, + .pwrdm_set_lowpwrstchange = am33xx_pwrdm_set_lowpwrstchange, + .pwrdm_read_mem_pwrst = am33xx_pwrdm_read_mem_pwrst, + .pwrdm_read_mem_retst = am33xx_pwrdm_read_mem_retst, + .pwrdm_set_mem_onst = am33xx_pwrdm_set_mem_onst, + .pwrdm_set_mem_retst = am33xx_pwrdm_set_mem_retst, + .pwrdm_wait_transition = am33xx_pwrdm_wait_transition, + .pwrdm_has_voltdm = am33xx_check_vcvp, + .pwrdm_save_context = am33xx_pwrdm_save_context, + .pwrdm_restore_context = am33xx_pwrdm_restore_context, +}; + +static struct prm_ll_data am33xx_prm_ll_data = { + .assert_hardreset = am33xx_prm_assert_hardreset, + .deassert_hardreset = am33xx_prm_deassert_hardreset, + .is_hardreset_asserted = am33xx_prm_is_hardreset_asserted, + .reset_system = am33xx_prm_global_warm_sw_reset, +}; + +int __init am33xx_prm_init(const struct omap_prcm_init_data *data) +{ + return prm_register(&am33xx_prm_ll_data); +} + +static void __exit am33xx_prm_exit(void) +{ + prm_unregister(&am33xx_prm_ll_data); +} +__exitcall(am33xx_prm_exit); |