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;
}
/**
* 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
* @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.
*/
int am33xx_prm_is_hardreset_asserted(u8 shift, s16 inst, u16 rstctrl_offs)
{
u32 v;
v = am33xx_prm_read_reg(inst, rstctrl_offs);
v &= 1 << shift;
v >>= shift;
return v;
}
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 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_prev_pwrst(struct powerdomain *pwrdm)
{
u32 v;
v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
v &= AM33XX_LASTPOWERSTATEENTERED_MASK;
v >>= AM33XX_LASTPOWERSTATEENTERED_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;
}
/* Read-modify-write a register in PRM. Caller must lock */
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_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);
}
/**
* am3xx_restart - trigger a software restart of the SoC
* @mode: the "reboot mode", see arch/arm/kernel/{setup,process}.c
* @cmd: passed from the userspace program rebooting the system (if provided)
*
* Resets the SoC. For @cmd, see the 'reboot' syscall in
* kernel/sys.c. No return value.
*/
void am33xx_restart(enum reboot_mode mode, const char *cmd)
{
/* TODO: Handle mode and cmd if necessary */
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 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_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 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);
}
