linux/drivers/net/ethernet/mscc/ocelot_io.c

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// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
* Microsemi Ocelot Switch driver
*
* Copyright (c) 2017 Microsemi Corporation
*/
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include "ocelot.h"
int __ocelot_bulk_read_ix(struct ocelot *ocelot, enum ocelot_reg reg,
u32 offset, void *buf, int count)
{
enum ocelot_target target;
u32 addr;
ocelot_reg_to_target_addr(ocelot, reg, &target, &addr);
WARN_ON(!target);
return regmap_bulk_read(ocelot->targets[target], addr + offset,
buf, count);
}
EXPORT_SYMBOL_GPL(__ocelot_bulk_read_ix);
u32 __ocelot_read_ix(struct ocelot *ocelot, enum ocelot_reg reg, u32 offset)
{
enum ocelot_target target;
u32 addr, val;
ocelot_reg_to_target_addr(ocelot, reg, &target, &addr);
WARN_ON(!target);
regmap_read(ocelot->targets[target], addr + offset, &val);
return val;
}
EXPORT_SYMBOL_GPL(__ocelot_read_ix);
void __ocelot_write_ix(struct ocelot *ocelot, u32 val, enum ocelot_reg reg,
u32 offset)
{
enum ocelot_target target;
u32 addr;
ocelot_reg_to_target_addr(ocelot, reg, &target, &addr);
WARN_ON(!target);
regmap_write(ocelot->targets[target], addr + offset, val);
}
EXPORT_SYMBOL_GPL(__ocelot_write_ix);
void __ocelot_rmw_ix(struct ocelot *ocelot, u32 val, u32 mask,
enum ocelot_reg reg, u32 offset)
{
enum ocelot_target target;
u32 addr;
ocelot_reg_to_target_addr(ocelot, reg, &target, &addr);
WARN_ON(!target);
regmap_update_bits(ocelot->targets[target], addr + offset, mask, val);
}
EXPORT_SYMBOL_GPL(__ocelot_rmw_ix);
u32 ocelot_port_readl(struct ocelot_port *port, enum ocelot_reg reg)
{
struct ocelot *ocelot = port->ocelot;
u16 target = reg >> TARGET_OFFSET;
u32 val;
WARN_ON(!target);
regmap_read(port->target, ocelot->map[target][reg & REG_MASK], &val);
return val;
}
EXPORT_SYMBOL_GPL(ocelot_port_readl);
void ocelot_port_writel(struct ocelot_port *port, u32 val, enum ocelot_reg reg)
{
struct ocelot *ocelot = port->ocelot;
u16 target = reg >> TARGET_OFFSET;
WARN_ON(!target);
regmap_write(port->target, ocelot->map[target][reg & REG_MASK], val);
}
EXPORT_SYMBOL_GPL(ocelot_port_writel);
void ocelot_port_rmwl(struct ocelot_port *port, u32 val, u32 mask,
enum ocelot_reg reg)
net: dsa: felix: implement port flushing on .phylink_mac_link_down There are several issues which may be seen when the link goes down while forwarding traffic, all of which can be attributed to the fact that the port flushing procedure from the reference manual was not closely followed. With flow control enabled on both the ingress port and the egress port, it may happen when a link goes down that Ethernet packets are in flight. In flow control mode, frames are held back and not dropped. When there is enough traffic in flight (example: iperf3 TCP), then the ingress port might enter congestion and never exit that state. This is a problem, because it is the egress port's link that went down, and that has caused the inability of the ingress port to send packets to any other port. This is solved by flushing the egress port's queues when it goes down. There is also a problem when performing stream splitting for IEEE 802.1CB traffic (not yet upstream, but a sort of multicast, basically). There, if one port from the destination ports mask goes down, splitting the stream towards the other destinations will no longer be performed. This can be traced down to this line: ocelot_port_writel(ocelot_port, 0, DEV_MAC_ENA_CFG); which should have been instead, as per the reference manual: ocelot_port_rmwl(ocelot_port, 0, DEV_MAC_ENA_CFG_RX_ENA, DEV_MAC_ENA_CFG); Basically only DEV_MAC_ENA_CFG_RX_ENA should be disabled, but not DEV_MAC_ENA_CFG_TX_ENA - I don't have further insight into why that is the case, but apparently multicasting to several ports will cause issues if at least one of them doesn't have DEV_MAC_ENA_CFG_TX_ENA set. I am not sure what the state of the Ocelot VSC7514 driver is, but probably not as bad as Felix/Seville, since VSC7514 uses phylib and has the following in ocelot_adjust_link: if (!phydev->link) return; therefore the port is not really put down when the link is lost, unlike the DSA drivers which use .phylink_mac_link_down for that. Nonetheless, I put ocelot_port_flush() in the common ocelot.c because it needs to access some registers from drivers/net/ethernet/mscc/ocelot_rew.h which are not exported in include/soc/mscc/ and a bugfix patch should probably not move headers around. Fixes: bdeced75b13f ("net: dsa: felix: Add PCS operations for PHYLINK") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-08 19:36:27 +02:00
{
u32 cur = ocelot_port_readl(port, reg);
ocelot_port_writel(port, (cur & (~mask)) | val, reg);
}
EXPORT_SYMBOL_GPL(ocelot_port_rmwl);
net: dsa: felix: implement port flushing on .phylink_mac_link_down There are several issues which may be seen when the link goes down while forwarding traffic, all of which can be attributed to the fact that the port flushing procedure from the reference manual was not closely followed. With flow control enabled on both the ingress port and the egress port, it may happen when a link goes down that Ethernet packets are in flight. In flow control mode, frames are held back and not dropped. When there is enough traffic in flight (example: iperf3 TCP), then the ingress port might enter congestion and never exit that state. This is a problem, because it is the egress port's link that went down, and that has caused the inability of the ingress port to send packets to any other port. This is solved by flushing the egress port's queues when it goes down. There is also a problem when performing stream splitting for IEEE 802.1CB traffic (not yet upstream, but a sort of multicast, basically). There, if one port from the destination ports mask goes down, splitting the stream towards the other destinations will no longer be performed. This can be traced down to this line: ocelot_port_writel(ocelot_port, 0, DEV_MAC_ENA_CFG); which should have been instead, as per the reference manual: ocelot_port_rmwl(ocelot_port, 0, DEV_MAC_ENA_CFG_RX_ENA, DEV_MAC_ENA_CFG); Basically only DEV_MAC_ENA_CFG_RX_ENA should be disabled, but not DEV_MAC_ENA_CFG_TX_ENA - I don't have further insight into why that is the case, but apparently multicasting to several ports will cause issues if at least one of them doesn't have DEV_MAC_ENA_CFG_TX_ENA set. I am not sure what the state of the Ocelot VSC7514 driver is, but probably not as bad as Felix/Seville, since VSC7514 uses phylib and has the following in ocelot_adjust_link: if (!phydev->link) return; therefore the port is not really put down when the link is lost, unlike the DSA drivers which use .phylink_mac_link_down for that. Nonetheless, I put ocelot_port_flush() in the common ocelot.c because it needs to access some registers from drivers/net/ethernet/mscc/ocelot_rew.h which are not exported in include/soc/mscc/ and a bugfix patch should probably not move headers around. Fixes: bdeced75b13f ("net: dsa: felix: Add PCS operations for PHYLINK") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-08 19:36:27 +02:00
net: mscc: ocelot: introduce a new ocelot_target_{read,write} API There are some targets (register blocks) in the Ocelot switch that are instantiated more than once. For example, the VCAP IS1, IS2 and ES0 blocks all share the same register layout for interacting with the cache for the TCAM and the action RAM. For the VCAPs, the procedure for servicing them is actually common. We just need an API specifying which VCAP we are talking to, and we do that via these raw ocelot_target_read and ocelot_target_write accessors. In plain ocelot_read, the target is encoded into the register enum itself: u16 target = reg >> TARGET_OFFSET; For the VCAPs, the registers are currently defined like this: enum ocelot_reg { [...] S2_CORE_UPDATE_CTRL = S2 << TARGET_OFFSET, S2_CORE_MV_CFG, S2_CACHE_ENTRY_DAT, S2_CACHE_MASK_DAT, S2_CACHE_ACTION_DAT, S2_CACHE_CNT_DAT, S2_CACHE_TG_DAT, [...] }; which is precisely what we want to avoid, because we'd have to duplicate the same register map for S1 and for S0, and then figure out how to pass VCAP instance-specific registers to the ocelot_read calls (basically another lookup table that undoes the effect of shifting with TARGET_OFFSET). So for some targets, propose a more raw API, similar to what is currently done with ocelot_port_readl and ocelot_port_writel. Those targets can only be accessed with ocelot_target_{read,write} and not with ocelot_{read,write} after the conversion, which is fine. The VCAP registers are not actually modified to use this new API as of this patch. They will be modified in the next one. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-30 01:27:21 +03:00
u32 __ocelot_target_read_ix(struct ocelot *ocelot, enum ocelot_target target,
u32 reg, u32 offset)
{
u32 val;
regmap_read(ocelot->targets[target],
ocelot->map[target][reg] + offset, &val);
return val;
}
void __ocelot_target_write_ix(struct ocelot *ocelot, enum ocelot_target target,
u32 val, u32 reg, u32 offset)
{
regmap_write(ocelot->targets[target],
ocelot->map[target][reg] + offset, val);
}
int ocelot_regfields_init(struct ocelot *ocelot,
const struct reg_field *const regfields)
{
unsigned int i;
u16 target;
for (i = 0; i < REGFIELD_MAX; i++) {
struct reg_field regfield = {};
u32 reg = regfields[i].reg;
if (!reg)
continue;
target = regfields[i].reg >> TARGET_OFFSET;
regfield.reg = ocelot->map[target][reg & REG_MASK];
regfield.lsb = regfields[i].lsb;
regfield.msb = regfields[i].msb;
regfield.id_size = regfields[i].id_size;
regfield.id_offset = regfields[i].id_offset;
ocelot->regfields[i] =
devm_regmap_field_alloc(ocelot->dev,
ocelot->targets[target],
regfield);
if (IS_ERR(ocelot->regfields[i]))
return PTR_ERR(ocelot->regfields[i]);
}
return 0;
}
EXPORT_SYMBOL_GPL(ocelot_regfields_init);
static struct regmap_config ocelot_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
struct regmap *ocelot_regmap_init(struct ocelot *ocelot, struct resource *res)
{
void __iomem *regs;
regs = devm_ioremap_resource(ocelot->dev, res);
if (IS_ERR(regs))
return ERR_CAST(regs);
ocelot_regmap_config.name = res->name;
return devm_regmap_init_mmio(ocelot->dev, regs, &ocelot_regmap_config);
}
EXPORT_SYMBOL_GPL(ocelot_regmap_init);