Commit 06a9a229 authored by Lucas Stach's avatar Lucas Stach Committed by Shawn Guo
Browse files

soc: imx: imx8m-blk-ctrl: set LCDIF panic read hurry level 



When the LCDIF block signals a panic condition due to the display FIFO
falling below the threshold, the priority at the NoC level is boosted
to the value set in the LCDIF_ARCACHE_CTRL register of i.MX8MP mediamix
blk-ctrl. Same as all other blk-ctrl registers this register is reset
when the domain is powered down. Initialize the panic hurry levels for
both LCIF interfaces to the maximium priority (same as downstream TF-A
and proven to work with the other priorities set in the interconnect
driver) when coming back from power down.

Signed-off-by: default avatarLucas Stach <l.stach@pengutronix.de>
Reviewed-by: default avatarMarco Felsch <m.felsch@pengutronix.de>
Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
parent 2cbee26e

drivers/soc/imx/imx8m-blk-ctrl.c

+21 −6
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
 * Copyright 2021 Pengutronix, Lucas Stach <kernel@pengutronix.de>

 */



#include <linux/bitfield.h>

#include <linux/device.h>

#include <linux/interconnect.h>

#include <linux/module.h>
@@ -654,6 +655,10 @@ static const struct imx8m_blk_ctrl_data imx8mn_disp_blk_ctl_dev_data = { 
	.num_domains = ARRAY_SIZE(imx8mn_disp_blk_ctl_domain_data),

};



#define LCDIF_ARCACHE_CTRL	0x4c

#define  LCDIF_1_RD_HURRY	GENMASK(15, 13)

#define  LCDIF_0_RD_HURRY	GENMASK(12, 10)



static int imx8mp_media_power_notifier(struct notifier_block *nb,

				unsigned long action, void *data)

{
@@ -667,14 +672,24 @@ static int imx8mp_media_power_notifier(struct notifier_block *nb, 
	regmap_set_bits(bc->regmap, BLK_CLK_EN, BIT(8));

	regmap_set_bits(bc->regmap, BLK_SFT_RSTN, BIT(8));



	if (action == GENPD_NOTIFY_ON) {

		/*

		 * On power up we have no software backchannel to the GPC to

		 * wait for the ADB handshake to happen, so we just delay for a

		 * bit. On power down the GPC driver waits for the handshake.

		 */

	if (action == GENPD_NOTIFY_ON)

		udelay(5);



		/*

		 * Set panic read hurry level for both LCDIF interfaces to

		 * maximum priority to minimize chances of display FIFO

		 * underflow.

		 */

		regmap_set_bits(bc->regmap, LCDIF_ARCACHE_CTRL,

				FIELD_PREP(LCDIF_1_RD_HURRY, 7) |

				FIELD_PREP(LCDIF_0_RD_HURRY, 7));

	}



	return NOTIFY_OK;

}