[PATCH 13/17] i3c: renesas: Update HW registers after SW computations are done

From: Claudiu Beznea <[email protected]>

renesas_i3c_bus_init() performs a number of computations and software
cache updates, interleaving them with hardware register writes. While
this works today, it makes it harder to minimize the time the controller
must remain powered when runtime PM is introduced.

Perform all software computations and cache updates first, then update
the hardware registers. This prepares for future runtime PM support.

Signed-off-by: Claudiu Beznea <[email protected]>
---
 drivers/i3c/master/renesas-i3c.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
index 865e67ac0fd2..631c9c5d8038 100644
--- a/drivers/i3c/master/renesas-i3c.c
+++ b/drivers/i3c/master/renesas-i3c.c
@@ -550,10 +550,6 @@ static int renesas_i3c_bus_init(struct i3c_master_controller *m)
 	if (!i3c->rate)
 		return -EINVAL;
 
-	ret = renesas_i3c_reset(i3c);
-	if (ret)
-		return ret;
-
 	i2c_total_ticks = DIV_ROUND_UP(i3c->rate, bus->scl_rate.i2c);
 	i3c_total_ticks = DIV_ROUND_UP(i3c->rate, bus->scl_rate.i3c);
 
@@ -604,27 +600,31 @@ static int renesas_i3c_bus_init(struct i3c_master_controller *m)
 			STDBR_SBRHO(double_SBR, od_high_ticks) |
 			STDBR_SBRLP(pp_low_ticks) |
 			STDBR_SBRHP(pp_high_ticks);
-	renesas_writel(i3c->regs, STDBR, i3c->i3c_STDBR);
 
 	/* Extended Bit Rate setting */
 	i3c->extbr = EXTBR_EBRLO(od_low_ticks) | EXTBR_EBRHO(od_high_ticks) |
 		     EXTBR_EBRLP(pp_low_ticks) | EXTBR_EBRHP(pp_high_ticks);
-	renesas_writel(i3c->regs, EXTBR, i3c->extbr);
-
-	renesas_writel(i3c->regs, REFCKCTL, REFCKCTL_IREFCKS(cks));
-	i3c->refclk_div = cks;
-
-	/* I3C hw init*/
-	renesas_i3c_hw_init(i3c);
 
 	ret = i3c_master_get_free_addr(m, 0);
 	if (ret < 0)
 		return ret;
 
+	info.dyn_addr = ret;
 	i3c->dyn_addr = ret;
-	renesas_writel(i3c->regs, MSDVAD, MSDVAD_MDYAD(ret) | MSDVAD_MDYADV);
+	i3c->refclk_div = cks;
+
+	ret = renesas_i3c_reset(i3c);
+	if (ret)
+		return ret;
+
+	renesas_writel(i3c->regs, STDBR, i3c->i3c_STDBR);
+	renesas_writel(i3c->regs, EXTBR, i3c->extbr);
+	renesas_writel(i3c->regs, REFCKCTL, REFCKCTL_IREFCKS(cks));
+	renesas_writel(i3c->regs, MSDVAD, MSDVAD_MDYAD(i3c->dyn_addr) | MSDVAD_MDYADV);
+
+	/* I3C hw init*/
+	renesas_i3c_hw_init(i3c);
 
-	info.dyn_addr = ret;
 	return i3c_master_set_info(&i3c->base, &info);
 }
 
-- 
2.43.0


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