[PATCH 4.9 025/108] net: thunderx: Fix PHY autoneg for SGMII QLM mode

Greg Kroah-Hartman
2017-06-15T17:58:58Z

From: Thanneeru Srinivasulu <tsrinivasulu@cavium.com>

[ Upstream commit 075ad765ef7541b2860de8408c165a92b78aefa3 ]

This patch fixes the case where there is no phydev attached
to a LMAC in DT due to non-existance of a PHY driver or due
to usage of non-stanadard PHY which doesn't support autoneg.
Changes dependeds on firmware to send correct info w.r.t
PHY and autoneg capability.

This patch also covers a case where a 10G/40G interface is used
as a 1G with convertors with Cortina PHY in between.

Signed-off-by: Thanneeru Srinivasulu <tsrinivasulu@cavium.com>
Signed-off-by: Sunil Goutham <sgoutham@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 108 +++++++++++++++++++---
drivers/net/ethernet/cavium/thunder/thunder_bgx.h | 5 +
2 files changed, 101 insertions(+), 12 deletions(-)

--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
@@ -31,6 +31,7 @@ struct lmac {
u8 lmac_type;
u8 lane_to_sds;
bool use_training;
+ bool autoneg;
bool link_up;
int lmacid; /* ID within BGX */
int lmacid_bd; /* ID on board */
@@ -418,7 +419,17 @@ static int bgx_lmac_sgmii_init(struct bg
/* power down, reset autoneg, autoneg enable */
cfg = bgx_reg_read(bgx, lmacid, BGX_GMP_PCS_MRX_CTL);
cfg &= ~PCS_MRX_CTL_PWR_DN;
- cfg |= (PCS_MRX_CTL_RST_AN | PCS_MRX_CTL_AN_EN);
+ cfg |= PCS_MRX_CTL_RST_AN;
+ if (lmac->phydev) {
+ cfg |= PCS_MRX_CTL_AN_EN;
+ } else {
+ /* In scenarios where PHY driver is not present or it's a
+ * non-standard PHY, FW sets AN_EN to inform Linux driver
+ * to do auto-neg and link polling or not.
+ */
+ if (cfg & PCS_MRX_CTL_AN_EN)
+ lmac->autoneg = true;
+ }
bgx_reg_write(bgx, lmacid, BGX_GMP_PCS_MRX_CTL, cfg);

if (lmac->lmac_type == BGX_MODE_QSGMII) {
@@ -429,7 +440,7 @@ static int bgx_lmac_sgmii_init(struct bg
return 0;
}

- if (lmac->lmac_type == BGX_MODE_SGMII) {
+ if ((lmac->lmac_type == BGX_MODE_SGMII) && lmac->phydev) {
if (bgx_poll_reg(bgx, lmacid, BGX_GMP_PCS_MRX_STATUS,
PCS_MRX_STATUS_AN_CPT, false)) {
dev_err(&bgx->pdev->dev, "BGX AN_CPT not completed\n");
@@ -623,12 +634,71 @@ static int bgx_xaui_check_link(struct lm
return -1;
}

+static void bgx_poll_for_sgmii_link(struct lmac *lmac)
+{
+ u64 pcs_link, an_result;
+ u8 speed;
+
+ pcs_link = bgx_reg_read(lmac->bgx, lmac->lmacid,
+ BGX_GMP_PCS_MRX_STATUS);
+
+ /*Link state bit is sticky, read it again*/
+ if (!(pcs_link & PCS_MRX_STATUS_LINK))
+ pcs_link = bgx_reg_read(lmac->bgx, lmac->lmacid,
+ BGX_GMP_PCS_MRX_STATUS);
+
+ if (bgx_poll_reg(lmac->bgx, lmac->lmacid, BGX_GMP_PCS_MRX_STATUS,
+ PCS_MRX_STATUS_AN_CPT, false)) {
+ lmac->link_up = false;
+ lmac->last_speed = SPEED_UNKNOWN;
+ lmac->last_duplex = DUPLEX_UNKNOWN;
+ goto next_poll;
+ }
+
+ lmac->link_up = ((pcs_link & PCS_MRX_STATUS_LINK) != 0) ? true : false;
+ an_result = bgx_reg_read(lmac->bgx, lmac->lmacid,
+ BGX_GMP_PCS_ANX_AN_RESULTS);
+
+ speed = (an_result >> 3) & 0x3;
+ lmac->last_duplex = (an_result >> 1) & 0x1;
+ switch (speed) {
+ case 0:
+ lmac->last_speed = 10;
+ break;
+ case 1:
+ lmac->last_speed = 100;
+ break;
+ case 2:
+ lmac->last_speed = 1000;
+ break;
+ default:
+ lmac->link_up = false;
+ lmac->last_speed = SPEED_UNKNOWN;
+ lmac->last_duplex = DUPLEX_UNKNOWN;
+ break;
+ }
+
+next_poll:
+
+ if (lmac->last_link != lmac->link_up) {
+ if (lmac->link_up)
+ bgx_sgmii_change_link_state(lmac);
+ lmac->last_link = lmac->link_up;
+ }
+
+ queue_delayed_work(lmac->check_link, &lmac->dwork, HZ * 3);
+}
+
static void bgx_poll_for_link(struct work_struct *work)
{
struct lmac *lmac;
u64 spu_link, smu_link;

lmac = container_of(work, struct lmac, dwork.work);
+ if (lmac->is_sgmii) {
+ bgx_poll_for_sgmii_link(lmac);
+ return;
+ }

/* Receive link is latching low. Force it high and verify it */
bgx_reg_modify(lmac->bgx, lmac->lmacid,
@@ -720,9 +790,21 @@ static int bgx_lmac_enable(struct bgx *b
(lmac->lmac_type != BGX_MODE_XLAUI) &&
(lmac->lmac_type != BGX_MODE_40G_KR) &&
(lmac->lmac_type != BGX_MODE_10G_KR)) {
- if (!lmac->phydev)
- return -ENODEV;
-
+ if (!lmac->phydev) {
+ if (lmac->autoneg) {
+ bgx_reg_write(bgx, lmacid,
+ BGX_GMP_PCS_LINKX_TIMER,
+ PCS_LINKX_TIMER_COUNT);
+ goto poll;
+ } else {
+ /* Default to below link speed and duplex */
+ lmac->link_up = true;
+ lmac->last_speed = 1000;
+ lmac->last_duplex = 1;
+ bgx_sgmii_change_link_state(lmac);
+ return 0;
+ }
+ }
lmac->phydev->dev_flags = 0;

if (phy_connect_direct(&lmac->netdev, lmac->phydev,
@@ -731,15 +813,17 @@ static int bgx_lmac_enable(struct bgx *b
return -ENODEV;

phy_start_aneg(lmac->phydev);
- } else {
- lmac->check_link = alloc_workqueue("check_link", WQ_UNBOUND |
- WQ_MEM_RECLAIM, 1);
- if (!lmac->check_link)
- return -ENOMEM;
- INIT_DELAYED_WORK(&lmac->dwork, bgx_poll_for_link);
- queue_delayed_work(lmac->check_link, &lmac->dwork, 0);
+ return 0;
}

+poll:
+ lmac->check_link = alloc_workqueue("check_link", WQ_UNBOUND |
+ WQ_MEM_RECLAIM, 1);
+ if (!lmac->check_link)
+ return -ENOMEM;
+ INIT_DELAYED_WORK(&lmac->dwork, bgx_poll_for_link);
+ queue_delayed_work(lmac->check_link, &lmac->dwork, 0);
+
return 0;
}

--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.h
@@ -144,10 +144,15 @@
#define PCS_MRX_CTL_LOOPBACK1 BIT_ULL(14)
#define PCS_MRX_CTL_RESET BIT_ULL(15)
#define BGX_GMP_PCS_MRX_STATUS 0x30008
+#define PCS_MRX_STATUS_LINK BIT_ULL(2)
#define PCS_MRX_STATUS_AN_CPT BIT_ULL(5)
+#define BGX_GMP_PCS_ANX_ADV 0x30010
#define BGX_GMP_PCS_ANX_AN_RESULTS 0x30020
+#define BGX_GMP_PCS_LINKX_TIMER 0x30040
+#define PCS_LINKX_TIMER_COUNT 0x1E84
#define BGX_GMP_PCS_SGM_AN_ADV 0x30068
#define BGX_GMP_PCS_MISCX_CTL 0x30078
+#define PCS_MISC_CTL_MODE BIT_ULL(8)
#define PCS_MISC_CTL_DISP_EN BIT_ULL(13)
#define PCS_MISC_CTL_GMX_ENO BIT_ULL(11)
#define PCS_MISC_CTL_SAMP_PT_MASK 0x7Full