On 06.05.21 03:04, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> The i.MX8MM VPU power up sequence is a bit special, it must follow:
> 1. request power up
> 2. reset assert
> 3. reset deassert
>
> This change in this patch will not affect other domains, because
> the power domain default is in asserted state, unless bootloader
> deassert the reset. It also applies to GPU power domain.
>
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
I don't really like that there is a dependency on TF-A/bootloader as we never really know what they will do, but from my point of view the approach is ok and it seems to work properly as far as I have tested it (only with GPU).
Reviewed-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
Tested-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
> ---
> drivers/soc/imx/gpcv2.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
> index 65b562cbcc6d..325a34833ffa 100644
> --- a/drivers/soc/imx/gpcv2.c
> +++ b/drivers/soc/imx/gpcv2.c
> @@ -217,8 +217,6 @@ static int imx_pgc_power_up(struct generic_pm_domain *genpd)
> goto out_regulator_disable;
> }
>
> - reset_control_assert(domain->reset);
> -
> if (domain->bits.pxx) {
> /* request the domain to power up */
> regmap_update_bits(domain->regmap, GPC_PU_PGC_SW_PUP_REQ,
> @@ -241,6 +239,8 @@ static int imx_pgc_power_up(struct generic_pm_domain *genpd)
> GPC_PGC_CTRL_PCR);
> }
>
> + reset_control_assert(domain->reset);
> +
> /* delay for reset to propagate */
> udelay(5);
>
>
