[PATCH 5.4 061/155] fsl/fman: detect FMan erratum A050385

Greg Kroah-Hartman
2020-03-31T09:14:15Z

From: Madalin Bucur <madalin.bucur@nxp.com>

[ Upstream commit b281f7b93b258ce1419043bbd898a29254d5c9c7 ]

Detect the presence of the A050385 erratum.

Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/freescale/fman/Kconfig | 28 +++++++++++++++++++++
drivers/net/ethernet/freescale/fman/fman.c | 18 +++++++++++++
drivers/net/ethernet/freescale/fman/fman.h | 5 ++++
3 files changed, 51 insertions(+)

diff --git a/drivers/net/ethernet/freescale/fman/Kconfig b/drivers/net/ethernet/freescale/fman/Kconfig
index 0139cb9042ec7..34150182cc35c 100644
--- a/drivers/net/ethernet/freescale/fman/Kconfig
+++ b/drivers/net/ethernet/freescale/fman/Kconfig
@@ -8,3 +8,31 @@ config FSL_FMAN
help
Freescale Data-Path Acceleration Architecture Frame Manager
(FMan) support
+
+config DPAA_ERRATUM_A050385
+ bool
+ depends on ARM64 && FSL_DPAA
+ default y
+ help
+ DPAA FMan erratum A050385 software workaround implementation:
+ align buffers, data start, SG fragment length to avoid FMan DMA
+ splits.
+ FMAN DMA read or writes under heavy traffic load may cause FMAN
+ internal resource leak thus stopping further packet processing.
+ The FMAN internal queue can overflow when FMAN splits single
+ read or write transactions into multiple smaller transactions
+ such that more than 17 AXI transactions are in flight from FMAN
+ to interconnect. When the FMAN internal queue overflows, it can
+ stall further packet processing. The issue can occur with any
+ one of the following three conditions:
+ 1. FMAN AXI transaction crosses 4K address boundary (Errata
+ A010022)
+ 2. FMAN DMA address for an AXI transaction is not 16 byte
+ aligned, i.e. the last 4 bits of an address are non-zero
+ 3. Scatter Gather (SG) frames have more than one SG buffer in
+ the SG list and any one of the buffers, except the last
+ buffer in the SG list has data size that is not a multiple
+ of 16 bytes, i.e., other than 16, 32, 48, 64, etc.
+ With any one of the above three conditions present, there is
+ likelihood of stalled FMAN packet processing, especially under
+ stress with multiple ports injecting line-rate traffic.
diff --git a/drivers/net/ethernet/freescale/fman/fman.c b/drivers/net/ethernet/freescale/fman/fman.c
index 210749bf1eac1..4c2fa13a7dd7b 100644
--- a/drivers/net/ethernet/freescale/fman/fman.c
+++ b/drivers/net/ethernet/freescale/fman/fman.c
@@ -1,5 +1,6 @@
/*
* Copyright 2008-2015 Freescale Semiconductor Inc.
+ * Copyright 2020 NXP
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -566,6 +567,10 @@ struct fman_cfg {
u32 qmi_def_tnums_thresh;
};

+#ifdef CONFIG_DPAA_ERRATUM_A050385
+static bool fman_has_err_a050385;
+#endif
+
static irqreturn_t fman_exceptions(struct fman *fman,
enum fman_exceptions exception)
{
@@ -2514,6 +2519,14 @@ struct fman *fman_bind(struct device *fm_dev)
}
EXPORT_SYMBOL(fman_bind);

+#ifdef CONFIG_DPAA_ERRATUM_A050385
+bool fman_has_errata_a050385(void)
+{
+ return fman_has_err_a050385;
+}
+EXPORT_SYMBOL(fman_has_errata_a050385);
+#endif
+
static irqreturn_t fman_err_irq(int irq, void *handle)
{
struct fman *fman = (struct fman *)handle;
@@ -2841,6 +2854,11 @@ static struct fman *read_dts_node(struct platform_device *of_dev)
goto fman_free;
}

+#ifdef CONFIG_DPAA_ERRATUM_A050385
+ fman_has_err_a050385 =
+ of_property_read_bool(fm_node, "fsl,erratum-a050385");
+#endif
+
return fman;

fman_node_put:
diff --git a/drivers/net/ethernet/freescale/fman/fman.h b/drivers/net/ethernet/freescale/fman/fman.h
index 935c317fa6964..f2ede1360f03a 100644
--- a/drivers/net/ethernet/freescale/fman/fman.h
+++ b/drivers/net/ethernet/freescale/fman/fman.h
@@ -1,5 +1,6 @@
/*
* Copyright 2008-2015 Freescale Semiconductor Inc.
+ * Copyright 2020 NXP
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -398,6 +399,10 @@ u16 fman_get_max_frm(void);

int fman_get_rx_extra_headroom(void);

+#ifdef CONFIG_DPAA_ERRATUM_A050385
+bool fman_has_errata_a050385(void);
+#endif
+
struct fman *fman_bind(struct device *dev);

#endif /* __FM_H */
--
2.20.1