// SPDX-License-Identifier: GPL-2.0-only
/*
* AM33XX PRM functions
*
* Copyright (C) 2011-2012 Texas Instruments Incorporated - https://www.ti.com/
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/reboot.h>
#include "powerdomain.h"
#include "prm33xx.h"
#include "prm-regbits-33xx.h"
/* 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_sw_reset(void)
{
/*
* Historically AM33xx performed warm reset for all requested reboot_mode.
* Keep this behaviour unchanged for all except newly added REBOOT_COLD.
*/
u32 mask = AM33XX_RST_GLOBAL_WARM_SW_MASK;
if (prm_reboot_mode == REBOOT_COLD)
mask = AM33XX_RST_GLOBAL_COLD_SW_MASK;
am33xx_prm_rmw_reg_bits(mask,
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_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);
Codebase Browser
linux