Re: [PATCH v2 3/3] net: macb: add support for high speed interface
From: Russell King - ARM Linux admin
Date: Sun Dec 15 2019 - 10:20:18 EST
On Sun, Dec 15, 2019 at 03:12:49PM +0000, Russell King - ARM Linux admin wrote:
> On Fri, Dec 13, 2019 at 09:42:57AM +0000, Milind Parab wrote:
> > This patch add support for high speed USXGMII PCS and 10G
> > speed in Cadence ethernet controller driver.
> >
> > Signed-off-by: Milind Parab <mparab@xxxxxxxxxxx>
> > ---
> > drivers/net/ethernet/cadence/macb.h | 50 ++++++++
> > drivers/net/ethernet/cadence/macb_main.c | 138 ++++++++++++++++++++---
> > 2 files changed, 170 insertions(+), 18 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
> > index dbf7070fcdba..b731807d1c49 100644
> > --- a/drivers/net/ethernet/cadence/macb.h
> > +++ b/drivers/net/ethernet/cadence/macb.h
> > @@ -76,10 +76,12 @@
> > #define MACB_RBQPH 0x04D4
> >
> > /* GEM register offsets. */
> > +#define GEM_NCR 0x0000 /* Network Control */
> > #define GEM_NCFGR 0x0004 /* Network Config */
> > #define GEM_USRIO 0x000c /* User IO */
> > #define GEM_DMACFG 0x0010 /* DMA Configuration */
> > #define GEM_JML 0x0048 /* Jumbo Max Length */
> > +#define GEM_HS_MAC_CONFIG 0x0050 /* GEM high speed config */
> > #define GEM_HRB 0x0080 /* Hash Bottom */
> > #define GEM_HRT 0x0084 /* Hash Top */
> > #define GEM_SA1B 0x0088 /* Specific1 Bottom */
> > @@ -164,6 +166,9 @@
> > #define GEM_DCFG7 0x0298 /* Design Config 7 */
> > #define GEM_DCFG8 0x029C /* Design Config 8 */
> > #define GEM_DCFG10 0x02A4 /* Design Config 10 */
> > +#define GEM_DCFG12 0x02AC /* Design Config 12 */
> > +#define GEM_USX_CONTROL 0x0A80 /* USXGMII control register */
> > +#define GEM_USX_STATUS 0x0A88 /* USXGMII status register */
> >
> > #define GEM_TXBDCTRL 0x04cc /* TX Buffer Descriptor control register */
> > #define GEM_RXBDCTRL 0x04d0 /* RX Buffer Descriptor control register */
> > @@ -270,11 +275,19 @@
> > #define MACB_IRXFCS_OFFSET 19
> > #define MACB_IRXFCS_SIZE 1
> >
> > +/* GEM specific NCR bitfields. */
> > +#define GEM_ENABLE_HS_MAC_OFFSET 31
> > +#define GEM_ENABLE_HS_MAC_SIZE 1
> > +
> > /* GEM specific NCFGR bitfields. */
> > +#define GEM_FD_OFFSET 1 /* Full duplex */
> > +#define GEM_FD_SIZE 1
> > #define GEM_GBE_OFFSET 10 /* Gigabit mode enable */
> > #define GEM_GBE_SIZE 1
> > #define GEM_PCSSEL_OFFSET 11
> > #define GEM_PCSSEL_SIZE 1
> > +#define GEM_PAE_OFFSET 13 /* Pause enable */
> > +#define GEM_PAE_SIZE 1
> > #define GEM_CLK_OFFSET 18 /* MDC clock division */
> > #define GEM_CLK_SIZE 3
> > #define GEM_DBW_OFFSET 21 /* Data bus width */
> > @@ -455,11 +468,17 @@
> > #define MACB_REV_OFFSET 0
> > #define MACB_REV_SIZE 16
> >
> > +/* Bitfield in HS_MAC_CONFIG */
> > +#define GEM_HS_MAC_SPEED_OFFSET 0
> > +#define GEM_HS_MAC_SPEED_SIZE 3
> > +
> > /* Bitfields in DCFG1. */
> > #define GEM_IRQCOR_OFFSET 23
> > #define GEM_IRQCOR_SIZE 1
> > #define GEM_DBWDEF_OFFSET 25
> > #define GEM_DBWDEF_SIZE 3
> > +#define GEM_NO_PCS_OFFSET 0
> > +#define GEM_NO_PCS_SIZE 1
> >
> > /* Bitfields in DCFG2. */
> > #define GEM_RX_PKT_BUFF_OFFSET 20
> > @@ -494,6 +513,34 @@
> > #define GEM_RXBD_RDBUFF_OFFSET 8
> > #define GEM_RXBD_RDBUFF_SIZE 4
> >
> > +/* Bitfields in DCFG12. */
> > +#define GEM_HIGH_SPEED_OFFSET 26
> > +#define GEM_HIGH_SPEED_SIZE 1
> > +
> > +/* Bitfields in USX_CONTROL. */
> > +#define GEM_USX_CTRL_SPEED_OFFSET 14
> > +#define GEM_USX_CTRL_SPEED_SIZE 3
> > +#define GEM_SERDES_RATE_OFFSET 12
> > +#define GEM_SERDES_RATE_SIZE 2
> > +#define GEM_RX_SCR_BYPASS_OFFSET 9
> > +#define GEM_RX_SCR_BYPASS_SIZE 1
> > +#define GEM_TX_SCR_BYPASS_OFFSET 8
> > +#define GEM_TX_SCR_BYPASS_SIZE 1
> > +#define GEM_RX_SYNC_RESET_OFFSET 2
> > +#define GEM_RX_SYNC_RESET_SIZE 1
> > +#define GEM_TX_EN_OFFSET 1
> > +#define GEM_TX_EN_SIZE 1
> > +#define GEM_SIGNAL_OK_OFFSET 0
> > +#define GEM_SIGNAL_OK_SIZE 1
> > +
> > +/* Bitfields in USX_STATUS. */
> > +#define GEM_USX_TX_FAULT_OFFSET 28
> > +#define GEM_USX_TX_FAULT_SIZE 1
> > +#define GEM_USX_RX_FAULT_OFFSET 27
> > +#define GEM_USX_RX_FAULT_SIZE 1
> > +#define GEM_USX_BLOCK_LOCK_OFFSET 0
> > +#define GEM_USX_BLOCK_LOCK_SIZE 1
> > +
> > /* Bitfields in TISUBN */
> > #define GEM_SUBNSINCR_OFFSET 0
> > #define GEM_SUBNSINCRL_OFFSET 24
> > @@ -656,6 +703,8 @@
> > #define MACB_CAPS_GIGABIT_MODE_AVAILABLE 0x20000000
> > #define MACB_CAPS_SG_DISABLED 0x40000000
> > #define MACB_CAPS_MACB_IS_GEM 0x80000000
> > +#define MACB_CAPS_PCS 0x01000000
> > +#define MACB_CAPS_HIGH_SPEED 0x02000000
> >
> > /* LSO settings */
> > #define MACB_LSO_UFO_ENABLE 0x01
> > @@ -724,6 +773,7 @@
> > })
> >
> > #define MACB_READ_NSR(bp) macb_readl(bp, NSR)
> > +#define GEM_READ_USX_STATUS(bp) gem_readl(bp, USX_STATUS)
> >
> > /* struct macb_dma_desc - Hardware DMA descriptor
> > * @addr: DMA address of data buffer
> > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> > index ced32d2a85e1..5963a60d54b9 100644
> > --- a/drivers/net/ethernet/cadence/macb_main.c
> > +++ b/drivers/net/ethernet/cadence/macb_main.c
> > @@ -81,6 +81,14 @@ struct sifive_fu540_macb_mgmt {
> > #define MACB_WOL_HAS_MAGIC_PACKET (0x1 << 0)
> > #define MACB_WOL_ENABLED (0x1 << 1)
> >
> > +#define HS_MAC_SPEED_100M 0
> > +#define HS_MAC_SPEED_1000M 1
> > +#define HS_MAC_SPEED_2500M 2
> > +#define HS_MAC_SPEED_5000M 3
> > +#define HS_MAC_SPEED_10000M 4
> > +
> > +#define MACB_SERDES_RATE_10G 1
> > +
> > /* Graceful stop timeouts in us. We should allow up to
> > * 1 frame time (10 Mbits/s, full-duplex, ignoring collisions)
> > */
> > @@ -90,6 +98,8 @@ struct sifive_fu540_macb_mgmt {
> >
> > #define MACB_MDIO_TIMEOUT 1000000 /* in usecs */
> >
> > +#define MACB_USX_BLOCK_LOCK_TIMEOUT 1000000 /* in usecs */
> > +
> > /* DMA buffer descriptor might be different size
> > * depends on hardware configuration:
> > *
> > @@ -506,6 +516,7 @@ static void macb_validate(struct phylink_config *config,
> > state->interface != PHY_INTERFACE_MODE_RMII &&
> > state->interface != PHY_INTERFACE_MODE_GMII &&
> > state->interface != PHY_INTERFACE_MODE_SGMII &&
> > + state->interface != PHY_INTERFACE_MODE_USXGMII &&
> > !phy_interface_mode_is_rgmii(state->interface)) {
> > bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
> > return;
> > @@ -518,6 +529,13 @@ static void macb_validate(struct phylink_config *config,
> > return;
> > }
> >
> > + if (state->interface == PHY_INTERFACE_MODE_USXGMII &&
> > + !(bp->caps & MACB_CAPS_HIGH_SPEED &&
> > + bp->caps & MACB_CAPS_PCS)) {
> > + bitmap_zero(supported, __ETHTOOL_LINK_MODE_MASK_NBITS);
> > + return;
> > + }
> > +
> > phylink_set_port_modes(mask);
> > phylink_set(mask, Autoneg);
> > phylink_set(mask, Asym_Pause);
> > @@ -527,6 +545,22 @@ static void macb_validate(struct phylink_config *config,
> > phylink_set(mask, 100baseT_Half);
> > phylink_set(mask, 100baseT_Full);
> >
> > + if (bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE &&
> > + (state->interface == PHY_INTERFACE_MODE_NA ||
> > + state->interface == PHY_INTERFACE_MODE_USXGMII)) {
> > + phylink_set(mask, 10000baseCR_Full);
> > + phylink_set(mask, 10000baseER_Full);
> > + phylink_set(mask, 10000baseKR_Full);
> > + phylink_set(mask, 10000baseLR_Full);
> > + phylink_set(mask, 10000baseLRM_Full);
> > + phylink_set(mask, 10000baseSR_Full);
> > + phylink_set(mask, 10000baseT_Full);
> > + phylink_set(mask, 5000baseT_Full);
> > + phylink_set(mask, 2500baseX_Full);
> > + phylink_set(mask, 1000baseX_Full);
> > + phylink_set(mask, 1000baseT_Full);
> > + }
> > +
> > if (bp->caps & MACB_CAPS_GIGABIT_MODE_AVAILABLE &&
> > (state->interface == PHY_INTERFACE_MODE_NA ||
> > state->interface == PHY_INTERFACE_MODE_GMII ||
> > @@ -544,6 +578,60 @@ static void macb_validate(struct phylink_config *config,
> > __ETHTOOL_LINK_MODE_MASK_NBITS);
> > }
> >
> > +static int gem_mac_usx_configure(struct macb *bp,
> > + const struct phylink_link_state *state)
> > +{
> > + u32 speed, config, val;
> > + int ret;
> > +
> > + val = gem_readl(bp, NCFGR);
> > + val = GEM_BIT(PCSSEL) | (~GEM_BIT(SGMIIEN) & val);
> > + if (state->pause & MLO_PAUSE_TX)
> > + val |= GEM_BIT(PAE);
> > + gem_writel(bp, NCFGR, val);
> > + gem_writel(bp, NCR, gem_readl(bp, NCR) | GEM_BIT(ENABLE_HS_MAC));
> > + gem_writel(bp, NCFGR, gem_readl(bp, NCFGR) | GEM_BIT(FD));
> > + config = gem_readl(bp, USX_CONTROL);
> > + config = GEM_BFINS(SERDES_RATE, MACB_SERDES_RATE_10G, config);
> > + config &= ~GEM_BIT(TX_SCR_BYPASS);
> > + config &= ~GEM_BIT(RX_SCR_BYPASS);
> > + gem_writel(bp, USX_CONTROL, config | GEM_BIT(TX_EN));
> > + config = gem_readl(bp, USX_CONTROL);
> > + gem_writel(bp, USX_CONTROL, config | GEM_BIT(SIGNAL_OK));
> > + ret = readx_poll_timeout(GEM_READ_USX_STATUS, bp, val,
> > + val & GEM_BIT(USX_BLOCK_LOCK),
> > + 1, MACB_USX_BLOCK_LOCK_TIMEOUT);
> > + if (ret < 0) {
> > + netdev_warn(bp->dev, "USXGMII block lock failed");
> > + return -ETIMEDOUT;
> > + }
>
> I mentioned this last time around, so I'm a little surprised it's
> still here. As I already stated, there is no requirement that the
> USXGMII locks before any of these functions return.
>
> You're also waiting for up to a second in a work queue, which is not
> nice behaviour.
>
> > +
> > + switch (state->speed) {
> > + case SPEED_10000:
> > + speed = HS_MAC_SPEED_10000M;
> > + break;
> > + case SPEED_5000:
> > + speed = HS_MAC_SPEED_5000M;
> > + break;
> > + case SPEED_2500:
> > + speed = HS_MAC_SPEED_2500M;
> > + break;
> > + case SPEED_1000:
> > + speed = HS_MAC_SPEED_1000M;
> > + break;
> > + default:
> > + case SPEED_100:
> > + speed = HS_MAC_SPEED_100M;
> > + break;
>
> macb_validate() goes down to 10Mbps, but you don't handle that here.
> If it isn't supported, then macb_validate() shouldn't allow it for this
> mode.
>
> > + }
> > +
> > + gem_writel(bp, HS_MAC_CONFIG, GEM_BFINS(HS_MAC_SPEED, speed,
> > + gem_readl(bp, HS_MAC_CONFIG)));
> > + gem_writel(bp, USX_CONTROL, GEM_BFINS(USX_CTRL_SPEED, speed,
> > + gem_readl(bp, USX_CONTROL)));
> > + return 0;
> > +}
> > +
> > static void macb_mac_pcs_get_state(struct phylink_config *config,
> > struct phylink_link_state *state)
> > {
> > @@ -565,30 +653,39 @@ static void macb_mac_config(struct phylink_config *config, unsigned int mode,
> >
> > spin_lock_irqsave(&bp->lock, flags);
> >
> > - old_ctrl = ctrl = macb_or_gem_readl(bp, NCFGR);
> > + if (bp->phy_interface == PHY_INTERFACE_MODE_USXGMII) {
>
> Why bp->phy_interface and not state->interface?
>
> If you don't support selecting between USXGMII and other modes at
> runtime, should macb_validate() be allowing ethtool link modes for
> it when it's different from the configured setting?
>
> > + if (gem_mac_usx_configure(bp, state) < 0) {
> > + spin_unlock_irqrestore(&bp->lock, flags);
> > + phylink_mac_change(bp->phylink, false);
>
> I guess this is the reason you're waiting for the USXGMII block
> to lock - do you not have any way to raise an interrupt when
> something changes with the USXGMII (or for that matter SGMII)
> blocks? Without that, you're fixed to a single speed.
BTW, if you don't have an macb_mac_pcs_get_state() implementation,
and from what you described last time around, I don't see how SGMII
nor this new addition of USXGMII can work for you. Both these
protocols use in-band control words, which should be read and
interpreted in macb_mac_pcs_get_state().
What I think you're trying to do is to use your PCS PHY as a normal
PHY, or maybe you're ignoring the PCS PHY completely and relying on
an external PHY (and hence always using MLO_AN_PHY or MLO_AN_FIXED
mode.)
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up