Commit 81b04a80 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Revert "net: stmmac: correct MAC propagation delay" 

This reverts commit 20bf98c9.

Richard raised concerns about correctness of the code on previous
generations of the HW.

Fixes: 20bf98c9 ("net: stmmac: correct MAC propagation delay")
Link: https://lore.kernel.org/all/ZMGIuKVP7BEotbrn@hoboy.vegasvil.org/
Link: https://lore.kernel.org/r/20230726224054.3241127-1-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 85e2a2c4

drivers/net/ethernet/stmicro/stmmac/hwif.h

+0 −3
Original line number Diff line number Diff line
@@ -532,7 +532,6 @@ struct stmmac_hwtimestamp { 
	void (*get_systime) (void __iomem *ioaddr, u64 *systime);

	void (*get_ptptime)(void __iomem *ioaddr, u64 *ptp_time);

	void (*timestamp_interrupt)(struct stmmac_priv *priv);

	void (*correct_latency)(struct stmmac_priv *priv);

};



#define stmmac_config_hw_tstamping(__priv, __args...) \
@@ -551,8 +550,6 @@ struct stmmac_hwtimestamp { 
	stmmac_do_void_callback(__priv, ptp, get_ptptime, __args)

#define stmmac_timestamp_interrupt(__priv, __args...) \

	stmmac_do_void_callback(__priv, ptp, timestamp_interrupt, __args)

#define stmmac_correct_latency(__priv, __args...) \

	stmmac_do_void_callback(__priv, ptp, correct_latency, __args)



struct stmmac_tx_queue;

struct stmmac_rx_queue;

drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c

+0 −43
Original line number Diff line number Diff line
@@ -60,48 +60,6 @@ static void config_sub_second_increment(void __iomem *ioaddr, 
		*ssinc = data;

}



static void correct_latency(struct stmmac_priv *priv)

{

	void __iomem *ioaddr = priv->ptpaddr;

	u32 reg_tsic, reg_tsicsns;

	u32 reg_tsec, reg_tsecsns;

	u64 scaled_ns;

	u32 val;



	/* MAC-internal ingress latency */

	scaled_ns = readl(ioaddr + PTP_TS_INGR_LAT);



	/* See section 11.7.2.5.3.1 "Ingress Correction" on page 4001 of

	 * i.MX8MP Applications Processor Reference Manual Rev. 1, 06/2021

	 */

	val = readl(ioaddr + PTP_TCR);

	if (val & PTP_TCR_TSCTRLSSR)

		/* nanoseconds field is in decimal format with granularity of 1ns/bit */

		scaled_ns = ((u64)NSEC_PER_SEC << 16) - scaled_ns;

	else

		/* nanoseconds field is in binary format with granularity of ~0.466ns/bit */

		scaled_ns = ((1ULL << 31) << 16) -

			DIV_U64_ROUND_CLOSEST(scaled_ns * PSEC_PER_NSEC, 466U);



	reg_tsic = scaled_ns >> 16;

	reg_tsicsns = scaled_ns & 0xff00;



	/* set bit 31 for 2's compliment */

	reg_tsic |= BIT(31);



	writel(reg_tsic, ioaddr + PTP_TS_INGR_CORR_NS);

	writel(reg_tsicsns, ioaddr + PTP_TS_INGR_CORR_SNS);



	/* MAC-internal egress latency */

	scaled_ns = readl(ioaddr + PTP_TS_EGR_LAT);



	reg_tsec = scaled_ns >> 16;

	reg_tsecsns = scaled_ns & 0xff00;



	writel(reg_tsec, ioaddr + PTP_TS_EGR_CORR_NS);

	writel(reg_tsecsns, ioaddr + PTP_TS_EGR_CORR_SNS);

}



static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec)

{

	u32 value;
@@ -263,5 +221,4 @@ const struct stmmac_hwtimestamp stmmac_ptp = { 
	.get_systime = get_systime,

	.get_ptptime = get_ptptime,

	.timestamp_interrupt = timestamp_interrupt,

	.correct_latency = correct_latency,

};

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

+0 −4
Original line number Diff line number Diff line
@@ -909,8 +909,6 @@ static int stmmac_init_ptp(struct stmmac_priv *priv) 
	priv->hwts_tx_en = 0;

	priv->hwts_rx_en = 0;



	stmmac_correct_latency(priv, priv);



	return 0;

}
@@ -1096,8 +1094,6 @@ static void stmmac_mac_link_up(struct phylink_config *config, 


	if (priv->dma_cap.fpesel)

		stmmac_fpe_link_state_handle(priv, true);



	stmmac_correct_latency(priv, priv);

}



static const struct phylink_mac_ops stmmac_phylink_mac_ops = {

drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.h

+0 −6
Original line number Diff line number Diff line
@@ -26,12 +26,6 @@ 
#define	PTP_ACR		0x40	/* Auxiliary Control Reg */

#define	PTP_ATNR	0x48	/* Auxiliary Timestamp - Nanoseconds Reg */

#define	PTP_ATSR	0x4c	/* Auxiliary Timestamp - Seconds Reg */

#define	PTP_TS_INGR_CORR_NS	0x58	/* Ingress timestamp correction nanoseconds */

#define	PTP_TS_EGR_CORR_NS	0x5C	/* Egress timestamp correction nanoseconds*/

#define	PTP_TS_INGR_CORR_SNS	0x60	/* Ingress timestamp correction subnanoseconds */

#define	PTP_TS_EGR_CORR_SNS	0x64	/* Egress timestamp correction subnanoseconds */

#define	PTP_TS_INGR_LAT	0x68	/* MAC internal Ingress Latency */

#define	PTP_TS_EGR_LAT	0x6c	/* MAC internal Egress Latency */



#define	PTP_STNSUR_ADDSUB_SHIFT	31

#define	PTP_DIGITAL_ROLLOVER_MODE	0x3B9ACA00	/* 10e9-1 ns */