[PATCH net-next 5/9] net: sparx5: Add support for ptp clocks

From: Horatiu Vultur
Date: Fri Mar 04 2022 - 06:06:59 EST


The sparx5 has 3 PHC. Enable each of them, for now all the
timestamping is happening on the first PHC.

Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
---
.../net/ethernet/microchip/sparx5/Makefile | 3 +-
.../ethernet/microchip/sparx5/sparx5_main.c | 7 +
.../ethernet/microchip/sparx5/sparx5_main.h | 21 ++
.../ethernet/microchip/sparx5/sparx5_ptp.c | 326 ++++++++++++++++++
4 files changed, 356 insertions(+), 1 deletion(-)
create mode 100644 drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c

diff --git a/drivers/net/ethernet/microchip/sparx5/Makefile b/drivers/net/ethernet/microchip/sparx5/Makefile
index c271e86ee292..e9dd348a6ebb 100644
--- a/drivers/net/ethernet/microchip/sparx5/Makefile
+++ b/drivers/net/ethernet/microchip/sparx5/Makefile
@@ -7,4 +7,5 @@ obj-$(CONFIG_SPARX5_SWITCH) += sparx5-switch.o

sparx5-switch-objs := sparx5_main.o sparx5_packet.o \
sparx5_netdev.o sparx5_phylink.o sparx5_port.o sparx5_mactable.o sparx5_vlan.o \
- sparx5_switchdev.o sparx5_calendar.o sparx5_ethtool.o sparx5_fdma.o
+ sparx5_switchdev.o sparx5_calendar.o sparx5_ethtool.o sparx5_fdma.o \
+ sparx5_ptp.o
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
index e8d26b330945..f72da757d0fa 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
@@ -847,6 +847,12 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
dev_err(sparx5->dev, "Start failed\n");
goto cleanup_ports;
}
+
+ err = sparx5_ptp_init(sparx5);
+ if (err) {
+ dev_err(sparx5->dev, "PTP failed\n");
+ goto cleanup_ports;
+ }
goto cleanup_config;

cleanup_ports:
@@ -870,6 +876,7 @@ static int mchp_sparx5_remove(struct platform_device *pdev)
disable_irq(sparx5->fdma_irq);
sparx5->fdma_irq = -ENXIO;
}
+ sparx5_ptp_deinit(sparx5);
sparx5_fdma_stop(sparx5);
sparx5_cleanup_ports(sparx5);
/* Unregister netdevs */
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
index 6f0b6e60ceb8..cf68b3f90834 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
@@ -14,6 +14,8 @@
#include <linux/if_vlan.h>
#include <linux/bitmap.h>
#include <linux/phylink.h>
+#include <linux/net_tstamp.h>
+#include <linux/ptp_clock_kernel.h>
#include <linux/hrtimer.h>

#include "sparx5_main_regs.h"
@@ -79,6 +81,9 @@ enum sparx5_vlan_port_type {
#define FDMA_RX_DCB_MAX_DBS 15
#define FDMA_TX_DCB_MAX_DBS 1

+#define SPARX5_PHC_COUNT 3
+#define SPARX5_PHC_PORT 0
+
struct sparx5;

struct sparx5_db_hw {
@@ -178,6 +183,14 @@ enum sparx5_core_clockfreq {
SPX5_CORE_CLOCK_625MHZ, /* 625MHZ core clock frequency */
};

+struct sparx5_phc {
+ struct ptp_clock *clock;
+ struct ptp_clock_info info;
+ struct hwtstamp_config hwtstamp_config;
+ struct sparx5 *sparx5;
+ u8 index;
+};
+
struct sparx5 {
struct platform_device *pdev;
struct device *dev;
@@ -225,6 +238,10 @@ struct sparx5 {
int fdma_irq;
struct sparx5_rx rx;
struct sparx5_tx tx;
+ /* PTP */
+ bool ptp;
+ struct sparx5_phc phc[SPARX5_PHC_COUNT];
+ spinlock_t ptp_clock_lock; /* lock for phc */
};

/* sparx5_switchdev.c */
@@ -294,6 +311,10 @@ int sparx5_register_netdevs(struct sparx5 *sparx5);
void sparx5_destroy_netdevs(struct sparx5 *sparx5);
void sparx5_unregister_netdevs(struct sparx5 *sparx5);

+/* sparx5_ptp.c */
+int sparx5_ptp_init(struct sparx5 *sparx5);
+void sparx5_ptp_deinit(struct sparx5 *sparx5);
+
/* Clock period in picoseconds */
static inline u32 sparx5_clk_period(enum sparx5_core_clockfreq cclock)
{
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c b/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c
new file mode 100644
index 000000000000..0203d872929c
--- /dev/null
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_ptp.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Microchip Sparx5 Switch driver
+ *
+ * Copyright (c) 2021 Microchip Technology Inc. and its subsidiaries.
+ *
+ * The Sparx5 Chip Register Model can be browsed at this location:
+ * https://github.com/microchip-ung/sparx-5_reginfo
+ */
+#include <linux/ptp_classify.h>
+
+#include "sparx5_main_regs.h"
+#include "sparx5_main.h"
+
+#define SPARX5_MAX_PTP_ID 512
+
+#define TOD_ACC_PIN 0x4
+
+enum {
+ PTP_PIN_ACTION_IDLE = 0,
+ PTP_PIN_ACTION_LOAD,
+ PTP_PIN_ACTION_SAVE,
+ PTP_PIN_ACTION_CLOCK,
+ PTP_PIN_ACTION_DELTA,
+ PTP_PIN_ACTION_TOD
+};
+
+static u64 sparx5_ptp_get_1ppm(struct sparx5 *sparx5)
+{
+ /* Represents 1ppm adjustment in 2^59 format with 1.59687500000(625)
+ * 1.99609375000(500), 3.99218750000(250) as reference
+ * The value is calculated as following:
+ * (1/1000000)/((2^-59)/X)
+ */
+
+ u64 res;
+
+ switch (sparx5->coreclock) {
+ case SPX5_CORE_CLOCK_250MHZ:
+ res = 2301339409586;
+ break;
+ case SPX5_CORE_CLOCK_500MHZ:
+ res = 1150669704793;
+ break;
+ case SPX5_CORE_CLOCK_625MHZ:
+ res = 920535763834;
+ break;
+ default:
+ WARN_ON("Invalid core clock");
+ break;
+ }
+
+ return res;
+}
+
+static u64 sparx5_ptp_get_nominal_value(struct sparx5 *sparx5)
+{
+ u64 res;
+
+ switch (sparx5->coreclock) {
+ case SPX5_CORE_CLOCK_250MHZ:
+ res = 0x1FF0000000000000;
+ break;
+ case SPX5_CORE_CLOCK_500MHZ:
+ res = 0x0FF8000000000000;
+ break;
+ case SPX5_CORE_CLOCK_625MHZ:
+ res = 0x0CC6666666666666;
+ break;
+ default:
+ WARN_ON("Invalid core clock");
+ break;
+ }
+
+ return res;
+}
+
+static int sparx5_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
+{
+ struct sparx5_phc *phc = container_of(ptp, struct sparx5_phc, info);
+ struct sparx5 *sparx5 = phc->sparx5;
+ unsigned long flags;
+ bool neg_adj = 0;
+ u64 tod_inc;
+ u64 ref;
+
+ if (!scaled_ppm)
+ return 0;
+
+ if (scaled_ppm < 0) {
+ neg_adj = 1;
+ scaled_ppm = -scaled_ppm;
+ }
+
+ tod_inc = sparx5_ptp_get_nominal_value(sparx5);
+
+ /* The multiplication is split in 2 separate additions because of
+ * overflow issues. If scaled_ppm with 16bit fractional part was bigger
+ * than 20ppm then we got overflow.
+ */
+ ref = sparx5_ptp_get_1ppm(sparx5) * (scaled_ppm >> 16);
+ ref += (sparx5_ptp_get_1ppm(sparx5) * (0xffff & scaled_ppm)) >> 16;
+ tod_inc = neg_adj ? tod_inc - ref : tod_inc + ref;
+
+ spin_lock_irqsave(&sparx5->ptp_clock_lock, flags);
+
+ spx5_rmw(PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS_SET(1 << BIT(phc->index)),
+ PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS,
+ sparx5, PTP_PTP_DOM_CFG);
+
+ spx5_wr((u32)tod_inc & 0xFFFFFFFF, sparx5,
+ PTP_CLK_PER_CFG(phc->index, 0));
+ spx5_wr((u32)(tod_inc >> 32), sparx5,
+ PTP_CLK_PER_CFG(phc->index, 1));
+
+ spx5_rmw(PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS_SET(0),
+ PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS, sparx5,
+ PTP_PTP_DOM_CFG);
+
+ spin_unlock_irqrestore(&sparx5->ptp_clock_lock, flags);
+
+ return 0;
+}
+
+static int sparx5_ptp_settime64(struct ptp_clock_info *ptp,
+ const struct timespec64 *ts)
+{
+ struct sparx5_phc *phc = container_of(ptp, struct sparx5_phc, info);
+ struct sparx5 *sparx5 = phc->sparx5;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sparx5->ptp_clock_lock, flags);
+
+ /* Must be in IDLE mode before the time can be loaded */
+ spx5_rmw(PTP_PTP_PIN_CFG_PTP_PIN_ACTION_SET(PTP_PIN_ACTION_IDLE) |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM_SET(phc->index) |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC_SET(0),
+ PTP_PTP_PIN_CFG_PTP_PIN_ACTION |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC,
+ sparx5, PTP_PTP_PIN_CFG(TOD_ACC_PIN));
+
+ /* Set new value */
+ spx5_wr(PTP_PTP_TOD_SEC_MSB_PTP_TOD_SEC_MSB_SET(upper_32_bits(ts->tv_sec)),
+ sparx5, PTP_PTP_TOD_SEC_MSB(TOD_ACC_PIN));
+ spx5_wr(lower_32_bits(ts->tv_sec),
+ sparx5, PTP_PTP_TOD_SEC_LSB(TOD_ACC_PIN));
+ spx5_wr(ts->tv_nsec, sparx5, PTP_PTP_TOD_NSEC(TOD_ACC_PIN));
+
+ /* Apply new values */
+ spx5_rmw(PTP_PTP_PIN_CFG_PTP_PIN_ACTION_SET(PTP_PIN_ACTION_LOAD) |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM_SET(phc->index) |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC_SET(0),
+ PTP_PTP_PIN_CFG_PTP_PIN_ACTION |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC,
+ sparx5, PTP_PTP_PIN_CFG(TOD_ACC_PIN));
+
+ spin_unlock_irqrestore(&sparx5->ptp_clock_lock, flags);
+
+ return 0;
+}
+
+static int sparx5_ptp_gettime64(struct ptp_clock_info *ptp,
+ struct timespec64 *ts)
+{
+ struct sparx5_phc *phc = container_of(ptp, struct sparx5_phc, info);
+ struct sparx5 *sparx5 = phc->sparx5;
+ unsigned long flags;
+ time64_t s;
+ s64 ns;
+
+ spin_lock_irqsave(&sparx5->ptp_clock_lock, flags);
+
+ spx5_rmw(PTP_PTP_PIN_CFG_PTP_PIN_ACTION_SET(PTP_PIN_ACTION_SAVE) |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM_SET(phc->index) |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC_SET(0),
+ PTP_PTP_PIN_CFG_PTP_PIN_ACTION |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC,
+ sparx5, PTP_PTP_PIN_CFG(TOD_ACC_PIN));
+
+ s = spx5_rd(sparx5, PTP_PTP_TOD_SEC_MSB(TOD_ACC_PIN));
+ s <<= 32;
+ s |= spx5_rd(sparx5, PTP_PTP_TOD_SEC_LSB(TOD_ACC_PIN));
+ ns = spx5_rd(sparx5, PTP_PTP_TOD_NSEC(TOD_ACC_PIN));
+ ns &= PTP_PTP_TOD_NSEC_PTP_TOD_NSEC;
+
+ spin_unlock_irqrestore(&sparx5->ptp_clock_lock, flags);
+
+ /* Deal with negative values */
+ if ((ns & 0xFFFFFFF0) == 0x3FFFFFF0) {
+ s--;
+ ns &= 0xf;
+ ns += 999999984;
+ }
+
+ set_normalized_timespec64(ts, s, ns);
+ return 0;
+}
+
+static int sparx5_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+ struct sparx5_phc *phc = container_of(ptp, struct sparx5_phc, info);
+ struct sparx5 *sparx5 = phc->sparx5;
+
+ if (delta > -(NSEC_PER_SEC / 2) && delta < (NSEC_PER_SEC / 2)) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&sparx5->ptp_clock_lock, flags);
+
+ /* Must be in IDLE mode before the time can be loaded */
+ spx5_rmw(PTP_PTP_PIN_CFG_PTP_PIN_ACTION_SET(PTP_PIN_ACTION_IDLE) |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM_SET(phc->index) |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC_SET(0),
+ PTP_PTP_PIN_CFG_PTP_PIN_ACTION |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC,
+ sparx5, PTP_PTP_PIN_CFG(TOD_ACC_PIN));
+
+ spx5_wr(PTP_PTP_TOD_NSEC_PTP_TOD_NSEC_SET(delta),
+ sparx5, PTP_PTP_TOD_NSEC(TOD_ACC_PIN));
+
+ /* Adjust time with the value of PTP_TOD_NSEC */
+ spx5_rmw(PTP_PTP_PIN_CFG_PTP_PIN_ACTION_SET(PTP_PIN_ACTION_DELTA) |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM_SET(phc->index) |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC_SET(0),
+ PTP_PTP_PIN_CFG_PTP_PIN_ACTION |
+ PTP_PTP_PIN_CFG_PTP_PIN_DOM |
+ PTP_PTP_PIN_CFG_PTP_PIN_SYNC,
+ sparx5, PTP_PTP_PIN_CFG(TOD_ACC_PIN));
+
+ spin_unlock_irqrestore(&sparx5->ptp_clock_lock, flags);
+ } else {
+ /* Fall back using sparx5_ptp_settime64 which is not exact */
+ struct timespec64 ts;
+ u64 now;
+
+ sparx5_ptp_gettime64(ptp, &ts);
+
+ now = ktime_to_ns(timespec64_to_ktime(ts));
+ ts = ns_to_timespec64(now + delta);
+
+ sparx5_ptp_settime64(ptp, &ts);
+ }
+
+ return 0;
+}
+
+static struct ptp_clock_info sparx5_ptp_clock_info = {
+ .owner = THIS_MODULE,
+ .name = "sparx5 ptp",
+ .max_adj = 200000,
+ .gettime64 = sparx5_ptp_gettime64,
+ .settime64 = sparx5_ptp_settime64,
+ .adjtime = sparx5_ptp_adjtime,
+ .adjfine = sparx5_ptp_adjfine,
+};
+
+static int sparx5_ptp_phc_init(struct sparx5 *sparx5,
+ int index,
+ struct ptp_clock_info *clock_info)
+{
+ struct sparx5_phc *phc = &sparx5->phc[index];
+
+ phc->info = *clock_info;
+ phc->clock = ptp_clock_register(&phc->info, sparx5->dev);
+ if (IS_ERR(phc->clock))
+ return PTR_ERR(phc->clock);
+
+ phc->index = index;
+ phc->sparx5 = sparx5;
+
+ /* PTP Rx stamping is always enabled. */
+ phc->hwtstamp_config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
+
+ return 0;
+}
+
+int sparx5_ptp_init(struct sparx5 *sparx5)
+{
+ u64 tod_adj = sparx5_ptp_get_nominal_value(sparx5);
+ int err, i;
+
+ if (!sparx5->ptp)
+ return 0;
+
+ for (i = 0; i < SPARX5_PHC_COUNT; ++i) {
+ err = sparx5_ptp_phc_init(sparx5, i, &sparx5_ptp_clock_info);
+ if (err)
+ return err;
+ }
+
+ spin_lock_init(&sparx5->ptp_clock_lock);
+
+ /* Disable master counters */
+ spx5_wr(PTP_PTP_DOM_CFG_PTP_ENA_SET(0), sparx5, PTP_PTP_DOM_CFG);
+
+ /* Configure the nominal TOD increment per clock cycle */
+ spx5_rmw(PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS_SET(0x7),
+ PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS,
+ sparx5, PTP_PTP_DOM_CFG);
+
+ for (i = 0; i < SPARX5_PHC_COUNT; ++i) {
+ spx5_wr((u32)tod_adj & 0xFFFFFFFF, sparx5,
+ PTP_CLK_PER_CFG(i, 0));
+ spx5_wr((u32)(tod_adj >> 32), sparx5,
+ PTP_CLK_PER_CFG(i, 1));
+ }
+
+ spx5_rmw(PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS_SET(0),
+ PTP_PTP_DOM_CFG_PTP_CLKCFG_DIS,
+ sparx5, PTP_PTP_DOM_CFG);
+
+ /* Enable master counters */
+ spx5_wr(PTP_PTP_DOM_CFG_PTP_ENA_SET(0x7), sparx5, PTP_PTP_DOM_CFG);
+
+ return 0;
+}
+
+void sparx5_ptp_deinit(struct sparx5 *sparx5)
+{
+ int i;
+
+ for (i = 0; i < SPARX5_PHC_COUNT; ++i)
+ ptp_clock_unregister(sparx5->phc[i].clock);
+}
--
2.33.0