4.18-stable review patch. If anyone has any objections, please let me know.
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From: Kazuya Mizuguchi kazuya.mizuguchi.ks@renesas.com
[ Upstream commit 2fe397a3959de8a472f165e6d152f64cb77fa2cc ]
EtherAVB hardware requires 0 to be written to status register bits in order to clear them, however, care must be taken not to:
1. Clear other bits, by writing zero to them 2. Write one to reserved bits
This patch corrects the ravb driver with respect to the second point above. This is done by defining reserved bit masks for the affected registers and, after auditing the code, ensure all sites that may write a one to a reserved bit use are suitably masked.
Signed-off-by: Kazuya Mizuguchi kazuya.mizuguchi.ks@renesas.com Signed-off-by: Simon Horman horms+renesas@verge.net.au Reviewed-by: Sergei Shtylyov sergei.shtylyov@cogentembedded.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/renesas/ravb.h | 5 +++++ drivers/net/ethernet/renesas/ravb_main.c | 11 ++++++----- drivers/net/ethernet/renesas/ravb_ptp.c | 2 +- 3 files changed, 12 insertions(+), 6 deletions(-)
--- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -431,6 +431,7 @@ enum EIS_BIT { EIS_CULF1 = 0x00000080, EIS_TFFF = 0x00000100, EIS_QFS = 0x00010000, + EIS_RESERVED = (GENMASK(31, 17) | GENMASK(15, 11)), };
/* RIC0 */ @@ -475,6 +476,7 @@ enum RIS0_BIT { RIS0_FRF15 = 0x00008000, RIS0_FRF16 = 0x00010000, RIS0_FRF17 = 0x00020000, + RIS0_RESERVED = GENMASK(31, 18), };
/* RIC1 */ @@ -531,6 +533,7 @@ enum RIS2_BIT { RIS2_QFF16 = 0x00010000, RIS2_QFF17 = 0x00020000, RIS2_RFFF = 0x80000000, + RIS2_RESERVED = GENMASK(30, 18), };
/* TIC */ @@ -547,6 +550,7 @@ enum TIS_BIT { TIS_FTF1 = 0x00000002, /* Undocumented? */ TIS_TFUF = 0x00000100, TIS_TFWF = 0x00000200, + TIS_RESERVED = (GENMASK(31, 20) | GENMASK(15, 12) | GENMASK(7, 4)) };
/* ISS */ @@ -620,6 +624,7 @@ enum GIC_BIT { enum GIS_BIT { GIS_PTCF = 0x00000001, /* Undocumented? */ GIS_PTMF = 0x00000004, + GIS_RESERVED = GENMASK(15, 10), };
/* GIE (R-Car Gen3 only) */ --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -742,10 +742,11 @@ static void ravb_error_interrupt(struct u32 eis, ris2;
eis = ravb_read(ndev, EIS); - ravb_write(ndev, ~EIS_QFS, EIS); + ravb_write(ndev, ~(EIS_QFS | EIS_RESERVED), EIS); if (eis & EIS_QFS) { ris2 = ravb_read(ndev, RIS2); - ravb_write(ndev, ~(RIS2_QFF0 | RIS2_RFFF), RIS2); + ravb_write(ndev, ~(RIS2_QFF0 | RIS2_RFFF | RIS2_RESERVED), + RIS2);
/* Receive Descriptor Empty int */ if (ris2 & RIS2_QFF0) @@ -798,7 +799,7 @@ static bool ravb_timestamp_interrupt(str u32 tis = ravb_read(ndev, TIS);
if (tis & TIS_TFUF) { - ravb_write(ndev, ~TIS_TFUF, TIS); + ravb_write(ndev, ~(TIS_TFUF | TIS_RESERVED), TIS); ravb_get_tx_tstamp(ndev); return true; } @@ -933,7 +934,7 @@ static int ravb_poll(struct napi_struct /* Processing RX Descriptor Ring */ if (ris0 & mask) { /* Clear RX interrupt */ - ravb_write(ndev, ~mask, RIS0); + ravb_write(ndev, ~(mask | RIS0_RESERVED), RIS0); if (ravb_rx(ndev, "a, q)) goto out; } @@ -941,7 +942,7 @@ static int ravb_poll(struct napi_struct if (tis & mask) { spin_lock_irqsave(&priv->lock, flags); /* Clear TX interrupt */ - ravb_write(ndev, ~mask, TIS); + ravb_write(ndev, ~(mask | TIS_RESERVED), TIS); ravb_tx_free(ndev, q, true); netif_wake_subqueue(ndev, q); mmiowb(); --- a/drivers/net/ethernet/renesas/ravb_ptp.c +++ b/drivers/net/ethernet/renesas/ravb_ptp.c @@ -319,7 +319,7 @@ void ravb_ptp_interrupt(struct net_devic } }
- ravb_write(ndev, ~gis, GIS); + ravb_write(ndev, ~(gis | GIS_RESERVED), GIS); }
void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev)