Re: [PATCH 3/3] net: macb: add support for high speed interface

From: Russell King - ARM Linux admin
Date: Mon Dec 09 2019 - 06:36:22 EST

On Mon, Dec 09, 2019 at 11:16:16AM +0000, Milind Parab wrote:
> This patch add support for high speed USXGMII PCS and 10G
> speed in Cadence ethernet controller driver.

How has this been tested?

> Signed-off-by: Milind Parab <mparab@xxxxxxxxxxx>
> ---
> drivers/net/ethernet/cadence/macb.h | 50 ++++++++
> drivers/net/ethernet/cadence/macb_main.c | 142 ++++++++++++++++++++---
> 2 files changed, 174 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 17297b01e85e..710ee18a0ef0 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -81,6 +81,18 @@ struct sifive_fu540_macb_mgmt {
> #define MACB_WOL_HAS_MAGIC_PACKET (0x1 << 0)
> #define MACB_WOL_ENABLED (0x1 << 1)
>
> +enum {
> + HS_MAC_SPEED_100M,
> + HS_MAC_SPEED_1000M,
> + HS_MAC_SPEED_2500M,
> + HS_MAC_SPEED_5000M,
> + HS_MAC_SPEED_10000M,

Are these chip register definitions? Shouldn't you be relying on fixed
values for these, rather than their position in an enumerated list?

> +};
> +
> +enum {
> + 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 +102,8 @@ 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 +520,7 @@ 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 +533,13 @@ 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 +549,22 @@ 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 +582,60 @@ 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);

What if there's no signal to lock on to? That's treated as link down
and is not a failure.

> + if (ret < 0) {
> + netdev_warn(bp->dev, "USXGMII block lock failed");
> + return -ETIMEDOUT;
> + }
> +
> + 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;
> + }

So you only support fixed-mode (phy and fixed links) and not in-band
links here.

> +
> + 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 +657,39 @@ 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) {
> + if (gem_mac_usx_configure(bp, state) < 0) {
> + spin_unlock_irqrestore(&bp->lock, flags);
> + phylink_mac_change(bp->phylink, false);
> + return;
> + }
> + } else {
> + old_ctrl = ctrl = macb_or_gem_readl(bp, NCFGR);
>
> - /* Clear all the bits we might set later */
> - ctrl &= ~(GEM_BIT(GBE) | MACB_BIT(SPD) | MACB_BIT(FD) | MACB_BIT(PAE) |
> - GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL));
> + /* Clear all the bits we might set later */
> + ctrl &= ~(GEM_BIT(GBE) | MACB_BIT(SPD) |
> + MACB_BIT(FD) | MACB_BIT(PAE) |
> + GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL));
>
> - if (state->speed == SPEED_1000)
> - ctrl |= GEM_BIT(GBE);
> - else if (state->speed == SPEED_100)
> - ctrl |= MACB_BIT(SPD);
> + if (state->speed == SPEED_1000)
> + ctrl |= GEM_BIT(GBE);
> + else if (state->speed == SPEED_100)
> + ctrl |= MACB_BIT(SPD);
>
> - if (state->duplex)
> - ctrl |= MACB_BIT(FD);
> + if (state->duplex)
> + ctrl |= MACB_BIT(FD);
>
> - /* We do not support MLO_PAUSE_RX yet */
> - if (state->pause & MLO_PAUSE_TX)
> - ctrl |= MACB_BIT(PAE);
> + /* We do not support MLO_PAUSE_RX yet */
> + if (state->pause & MLO_PAUSE_TX)
> + ctrl |= MACB_BIT(PAE);
>
> - if (state->interface == PHY_INTERFACE_MODE_SGMII)
> - ctrl |= GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL);
> + if (state->interface == PHY_INTERFACE_MODE_SGMII)
> + ctrl |= GEM_BIT(SGMIIEN) | GEM_BIT(PCSSEL);
>
> - /* Apply the new configuration, if any */
> - if (old_ctrl ^ ctrl)
> - macb_or_gem_writel(bp, NCFGR, ctrl);
> + /* Apply the new configuration, if any */
> + if (old_ctrl ^ ctrl)
> + macb_or_gem_writel(bp, NCFGR, ctrl);
> + }
>
> bp->speed = state->speed;
>
> @@ -3399,6 +3500,11 @@ static void macb_configure_caps(struct macb *bp,
> dcfg = gem_readl(bp, DCFG1);
> if (GEM_BFEXT(IRQCOR, dcfg) == 0)
> bp->caps |= MACB_CAPS_ISR_CLEAR_ON_WRITE;
> + if (GEM_BFEXT(NO_PCS, dcfg) == 0)
> + bp->caps |= MACB_CAPS_PCS;
> + dcfg = gem_readl(bp, DCFG12);
> + if (GEM_BFEXT(HIGH_SPEED, dcfg) == 1)
> + bp->caps |= MACB_CAPS_HIGH_SPEED;
> dcfg = gem_readl(bp, DCFG2);
> if ((dcfg & (GEM_BIT(RX_PKT_BUFF) | GEM_BIT(TX_PKT_BUFF))) == 0)
> bp->caps |= MACB_CAPS_FIFO_MODE;
> --
> 2.17.1
>
>

--
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