[PATCH net v3 2/3] octeon_ep: ensure dbell BADDR updation

[Vimlesh Kumar <vimleshk@marvell.com>]

Make sure the OUT DBELL base address reflects the
latest values written to it.

Fix:
Add a wait until the OUT DBELL base address register
is updated with the DMA ring descriptor address,
and modify the setup_oq function to properly
handle failures.

Fixes: 0807dc76f3bf5 ("octeon_ep: support Octeon CN10K devices")
Signed-off-by: Sathesh Edara <sedara@marvell.com>
Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
Signed-off-by: Vimlesh Kumar <vimleshk@marvell.com>
---
V3:
- Use reverse christmas tree order variable declaration.
- Return error if timeout happens during setup oq.
 
V2: https://lore.kernel.org/all/20251219100751.3063135-3-vimleshk@marvell.com/

V1: https://lore.kernel.org/all/20251212122304.2562229-3-vimleshk@marvell.com/

 .../marvell/octeon_ep/octep_cn9k_pf.c         |  3 +-
 .../marvell/octeon_ep/octep_cnxk_pf.c         | 46 +++++++++++++++----
 .../ethernet/marvell/octeon_ep/octep_main.h   |  2 +-
 .../net/ethernet/marvell/octeon_ep/octep_rx.c |  4 +-
 4 files changed, 44 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_cn9k_pf.c b/drivers/net/ethernet/marvell/octeon_ep/octep_cn9k_pf.c
index 2574a6061e3d..2a5cebbf1ff8 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_cn9k_pf.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_cn9k_pf.c
@@ -307,7 +307,7 @@ static void octep_setup_iq_regs_cn93_pf(struct octep_device *oct, int iq_no)
 }
 
 /* Setup registers for a hardware Rx Queue  */
-static void octep_setup_oq_regs_cn93_pf(struct octep_device *oct, int oq_no)
+static int octep_setup_oq_regs_cn93_pf(struct octep_device *oct, int oq_no)
 {
 	u64 reg_val;
 	u64 oq_ctl = 0ULL;
@@ -355,6 +355,7 @@ static void octep_setup_oq_regs_cn93_pf(struct octep_device *oct, int oq_no)
 	reg_val = ((u64)time_threshold << 32) |
 		  CFG_GET_OQ_INTR_PKT(oct->conf);
 	octep_write_csr64(oct, CN93_SDP_R_OUT_INT_LEVELS(oq_no), reg_val);
+	return 0;
 }
 
 /* Setup registers for a PF mailbox */
diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_cnxk_pf.c b/drivers/net/ethernet/marvell/octeon_ep/octep_cnxk_pf.c
index 73cd0ca758f0..8d17ff71507f 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_cnxk_pf.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_cnxk_pf.c
@@ -8,6 +8,7 @@
 #include <linux/pci.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
+#include <linux/jiffies.h>
 
 #include "octep_config.h"
 #include "octep_main.h"
@@ -327,12 +328,14 @@ static void octep_setup_iq_regs_cnxk_pf(struct octep_device *oct, int iq_no)
 }
 
 /* Setup registers for a hardware Rx Queue  */
-static void octep_setup_oq_regs_cnxk_pf(struct octep_device *oct, int oq_no)
+static int octep_setup_oq_regs_cnxk_pf(struct octep_device *oct, int oq_no)
 {
-	u64 reg_val;
-	u64 oq_ctl = 0ULL;
-	u32 time_threshold = 0;
 	struct octep_oq *oq = oct->oq[oq_no];
+	unsigned long t_out_jiffies;
+	u32 time_threshold = 0;
+	u64 oq_ctl = 0ULL;
+	u64 reg_ba_val;
+	u64 reg_val;
 
 	oq_no += CFG_GET_PORTS_PF_SRN(oct->conf);
 	reg_val = octep_read_csr64(oct, CNXK_SDP_R_OUT_CONTROL(oq_no));
@@ -343,6 +346,36 @@ static void octep_setup_oq_regs_cnxk_pf(struct octep_device *oct, int oq_no)
 			reg_val = octep_read_csr64(oct, CNXK_SDP_R_OUT_CONTROL(oq_no));
 		} while (!(reg_val & CNXK_R_OUT_CTL_IDLE));
 	}
+	octep_write_csr64(oct, CNXK_SDP_R_OUT_WMARK(oq_no),  oq->max_count);
+	/* Wait for WMARK to get applied */
+	usleep_range(10, 15);
+
+	octep_write_csr64(oct, CNXK_SDP_R_OUT_SLIST_BADDR(oq_no),
+			  oq->desc_ring_dma);
+	octep_write_csr64(oct, CNXK_SDP_R_OUT_SLIST_RSIZE(oq_no),
+			  oq->max_count);
+	reg_ba_val = octep_read_csr64(oct, CNXK_SDP_R_OUT_SLIST_BADDR(oq_no));
+
+	if (reg_ba_val != oq->desc_ring_dma) {
+		t_out_jiffies = jiffies + 10 * HZ;
+		do {
+			if (reg_ba_val == ULLONG_MAX)
+				return -EFAULT;
+			octep_write_csr64(oct,
+					  CNXK_SDP_R_OUT_SLIST_BADDR(oq_no),
+					  oq->desc_ring_dma);
+			octep_write_csr64(oct,
+					  CNXK_SDP_R_OUT_SLIST_RSIZE(oq_no),
+					  oq->max_count);
+			reg_ba_val =
+			octep_read_csr64(oct,
+					 CNXK_SDP_R_OUT_SLIST_BADDR(oq_no));
+		} while ((reg_ba_val != oq->desc_ring_dma) &&
+			  time_before(jiffies, t_out_jiffies));
+
+		if (reg_ba_val != oq->desc_ring_dma)
+			return -EAGAIN;
+	}
 
 	reg_val &= ~(CNXK_R_OUT_CTL_IMODE);
 	reg_val &= ~(CNXK_R_OUT_CTL_ROR_P);
@@ -356,10 +389,6 @@ static void octep_setup_oq_regs_cnxk_pf(struct octep_device *oct, int oq_no)
 	reg_val |= (CNXK_R_OUT_CTL_ES_P);
 
 	octep_write_csr64(oct, CNXK_SDP_R_OUT_CONTROL(oq_no), reg_val);
-	octep_write_csr64(oct, CNXK_SDP_R_OUT_SLIST_BADDR(oq_no),
-			  oq->desc_ring_dma);
-	octep_write_csr64(oct, CNXK_SDP_R_OUT_SLIST_RSIZE(oq_no),
-			  oq->max_count);
 
 	oq_ctl = octep_read_csr64(oct, CNXK_SDP_R_OUT_CONTROL(oq_no));
 
@@ -385,6 +414,7 @@ static void octep_setup_oq_regs_cnxk_pf(struct octep_device *oct, int oq_no)
 	reg_val &= ~0xFFFFFFFFULL;
 	reg_val |= CFG_GET_OQ_WMARK(oct->conf);
 	octep_write_csr64(oct, CNXK_SDP_R_OUT_WMARK(oq_no), reg_val);
+	return 0;
 }
 
 /* Setup registers for a PF mailbox */
diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.h b/drivers/net/ethernet/marvell/octeon_ep/octep_main.h
index 81ac4267811c..35d0ff289a70 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.h
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.h
@@ -77,7 +77,7 @@ struct octep_pci_win_regs {
 
 struct octep_hw_ops {
 	void (*setup_iq_regs)(struct octep_device *oct, int q);
-	void (*setup_oq_regs)(struct octep_device *oct, int q);
+	int (*setup_oq_regs)(struct octep_device *oct, int q);
 	void (*setup_mbox_regs)(struct octep_device *oct, int mbox);
 
 	irqreturn_t (*mbox_intr_handler)(void *ioq_vector);
diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c
index 82b6b19e76b4..1581cc468d74 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_rx.c
@@ -170,7 +170,9 @@ static int octep_setup_oq(struct octep_device *oct, int q_no)
 		goto oq_fill_buff_err;
 
 	octep_oq_reset_indices(oq);
-	oct->hw_ops.setup_oq_regs(oct, q_no);
+	if (oct->hw_ops.setup_oq_regs(oct, q_no))
+		goto oq_fill_buff_err;
+
 	oct->num_oqs++;
 
 	return 0;
-- 
2.47.0