[PATCH 14/16] soc: imx: gpcv2: move reset assert after requesting domain power up

Peng Fan (OSS) peng.fan at oss.nxp.com
Thu Apr 29 08:30:48 BST 2021


From: Peng Fan <peng.fan at nxp.com>

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.

[Note: We expect bootloader leave the domain in asserted state,
but this may not always be true, so we might need another solution
to address the VPU domain requirements]

Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 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 d2ce47a5ebad..072f519462a5 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, 0);
 	}
 
+	reset_control_assert(domain->reset);
+
 	/* delay for reset to propagate */
 	udelay(5);
 
-- 
2.30.0




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