Commit 2a785307 authored by Stanley Chu's avatar Stanley Chu Committed by Alexandre Belloni
Browse files

i3c: master: svc: Fix npcm845 DAA process corruption 



When MCONFIG.SKEW=0 and MCONFIG.ODHPP=0, the ENTDAA transaction gets
corrupted and results in a no repeated-start condition at the end of
address assignment.

Workaround: Set MCONFIG.SKEW to 1 before initiating the DAA process.
After the DAA process is completed, return MCONFIG.SKEW to its previous
value.

Reviewed-by: default avatarFrank Li <Frank.Li@nxp.com>
Signed-off-by: default avatarStanley Chu <yschu@nuvoton.com>
Link: https://lore.kernel.org/r/20250306075429.2265183-6-yschu@nuvoton.com


Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent 4dd12e94

drivers/i3c/master/svc-i3c-master.c

+29 −1
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#define   SVC_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))

#define   SVC_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))

#define   SVC_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))

#define   SVC_I3C_MCONFIG_SKEW_MASK GENMASK(27, 25)

#define   SVC_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))



#define SVC_I3C_MCTRL        0x084
@@ -150,6 +151,16 @@ 
 * If it is a true SlvStart, the MSTATUS state is SLVREQ.

 */

#define SVC_I3C_QUIRK_FALSE_SLVSTART	BIT(1)

/*

 * SVC_I3C_QUIRK_DAA_CORRUPT:

 * When MCONFIG.SKEW=0 and MCONFIG.ODHPP=0, the ENTDAA transaction gets

 * corrupted and results in a no repeated-start condition at the end of

 * address assignment.

 * Workaround:

 * Set MCONFIG.SKEW to 1 before initiating the DAA process. After the DAA

 * process is completed, return MCONFIG.SKEW to its previous value.

 */

#define SVC_I3C_QUIRK_DAA_CORRUPT	BIT(2)



struct svc_i3c_cmd {

	u8 addr;
@@ -259,6 +270,13 @@ static inline bool svc_has_quirk(struct svc_i3c_master *master, u32 quirk) 
	return (master->drvdata->quirks & quirk);

}



static inline bool svc_has_daa_corrupt(struct svc_i3c_master *master)

{

	return ((master->drvdata->quirks & SVC_I3C_QUIRK_DAA_CORRUPT) &&

		!(master->mctrl_config &

		(SVC_I3C_MCONFIG_SKEW_MASK | SVC_I3C_MCONFIG_ODHPP(1))));

}



static inline bool is_events_enabled(struct svc_i3c_master *master, u32 mask)

{

	return !!(master->enabled_events & mask);
@@ -1146,7 +1164,16 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m) 
	}



	spin_lock_irqsave(&master->xferqueue.lock, flags);



	if (svc_has_daa_corrupt(master))

		writel(master->mctrl_config | SVC_I3C_MCONFIG_SKEW(1),

		       master->regs + SVC_I3C_MCONFIG);



	ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);



	if (svc_has_daa_corrupt(master))

		writel(master->mctrl_config, master->regs + SVC_I3C_MCONFIG);



	spin_unlock_irqrestore(&master->xferqueue.lock, flags);



	svc_i3c_master_clear_merrwarn(master);
@@ -2033,7 +2060,8 @@ static const struct dev_pm_ops svc_i3c_pm_ops = { 


static const struct svc_i3c_drvdata npcm845_drvdata = {

	.quirks = SVC_I3C_QUIRK_FIFO_EMPTY |

		SVC_I3C_QUIRK_FALSE_SLVSTART,

		SVC_I3C_QUIRK_FALSE_SLVSTART |

		SVC_I3C_QUIRK_DAA_CORRUPT,

};



static const struct svc_i3c_drvdata svc_default_drvdata = {};