Merge branch 'net-ethernet-renesas-rcar_gen4_ptp-add-v4h-support'

Niklas Söderlund says:

====================
net: ethernet: renesas: rcar_gen4_ptp: Add V4H support

This small series prepares the rcar_gen4_ptp to be useable both on both
R-Car S4 and V4H. The only in-tree driver that make use of this is
rswtich on S4. A new Ethernet (R-Car Ethernet TSN) driver for V4H is on
it's way that also will make use of rcar_gen4_ptp functionality.

Patch 1-2 are small improvements to the existing driver. While patch 3-4
adds V4H support. Finally patch 5 turns rcar_gen4_ptp into a separate
module to allow the gPTP functionality to be shared between the two
users without having to duplicate the code in each.

See each patch for changelog.
====================

Link: https://lore.kernel.org/r/20231121155306.515446-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

5 files changed, 49 insertions, 18 deletions

diff --git a/drivers/net/ethernet/renesas/Kconfig b/drivers/net/ethernet/renesas/Kconfig
index 8ef5b0241e64..733cbb6eb3ed 100644
--- a/drivers/net/ethernet/renesas/Kconfig
+++ b/drivers/net/ethernet/renesas/Kconfig
@@ -44,7 +44,16 @@ config RENESAS_ETHER_SWITCH
 	select CRC32
 	select MII
 	select PHYLINK
+	select RENESAS_GEN4_PTP
 	help
 	  Renesas Ethernet Switch device driver.
 
+config RENESAS_GEN4_PTP
+	tristate "Renesas R-Car Gen4 gPTP support" if COMPILE_TEST
+	select CRC32
+	select MII
+	select PHYLIB
+	help
+	  Renesas R-Car Gen4 gPTP device driver.
+
 endif # NET_VENDOR_RENESAS
diff --git a/drivers/net/ethernet/renesas/Makefile b/drivers/net/ethernet/renesas/Makefile
index e8fd85b5fe8f..9070acfd6aaf 100644
--- a/drivers/net/ethernet/renesas/Makefile
+++ b/drivers/net/ethernet/renesas/Makefile
@@ -8,5 +8,6 @@ obj-$(CONFIG_SH_ETH) += sh_eth.o
 ravb-objs := ravb_main.o ravb_ptp.o
 obj-$(CONFIG_RAVB) += ravb.o
 
-rswitch_drv-objs := rswitch.o rcar_gen4_ptp.o
-obj-$(CONFIG_RENESAS_ETHER_SWITCH) += rswitch_drv.o
+obj-$(CONFIG_RENESAS_ETHER_SWITCH) += rswitch.o
+
+obj-$(CONFIG_RENESAS_GEN4_PTP) += rcar_gen4_ptp.o
diff --git a/drivers/net/ethernet/renesas/rcar_gen4_ptp.c b/drivers/net/ethernet/renesas/rcar_gen4_ptp.c
index c007e33c47e1..72e7fcc56693 100644
--- a/drivers/net/ethernet/renesas/rcar_gen4_ptp.c
+++ b/drivers/net/ethernet/renesas/rcar_gen4_ptp.c
@@ -14,7 +14,7 @@
 #include "rcar_gen4_ptp.h"
 #define ptp_to_priv(ptp)	container_of(ptp, struct rcar_gen4_ptp_private, info)
 
-static const struct rcar_gen4_ptp_reg_offset s4_offs = {
+static const struct rcar_gen4_ptp_reg_offset gen4_offs = {
 	.enable = PTPTMEC,
 	.disable = PTPTMDC,
 	.increment = PTPTIVC0,
@@ -130,25 +130,42 @@ static struct ptp_clock_info rcar_gen4_ptp_info = {
 	.enable = rcar_gen4_ptp_enable,
 };
 
-static void rcar_gen4_ptp_set_offs(struct rcar_gen4_ptp_private *ptp_priv,
-				   enum rcar_gen4_ptp_reg_layout layout)
+static int rcar_gen4_ptp_set_offs(struct rcar_gen4_ptp_private *ptp_priv,
+				  enum rcar_gen4_ptp_reg_layout layout)
 {
-	WARN_ON(layout != RCAR_GEN4_PTP_REG_LAYOUT_S4);
+	if (layout != RCAR_GEN4_PTP_REG_LAYOUT)
+		return -EINVAL;
 
-	ptp_priv->offs = &s4_offs;
+	ptp_priv->offs = &gen4_offs;
+
+	return 0;
+}
+
+static s64 rcar_gen4_ptp_rate_to_increment(u32 rate)
+{
+	/* Timer increment in ns.
+	 * bit[31:27] - integer
+	 * bit[26:0]  - decimal
+	 * increment[ns] = perid[ns] * 2^27 => (1ns * 2^27) / rate[hz]
+	 */
+	return div_s64(1000000000LL << 27, rate);
 }
 
 int rcar_gen4_ptp_register(struct rcar_gen4_ptp_private *ptp_priv,
-			   enum rcar_gen4_ptp_reg_layout layout, u32 clock)
+			   enum rcar_gen4_ptp_reg_layout layout, u32 rate)
 {
+	int ret;
+
 	if (ptp_priv->initialized)
 		return 0;
 
 	spin_lock_init(&ptp_priv->lock);
 
-	rcar_gen4_ptp_set_offs(ptp_priv, layout);
+	ret = rcar_gen4_ptp_set_offs(ptp_priv, layout);
+	if (ret)
+		return ret;
 
-	ptp_priv->default_addend = clock;
+	ptp_priv->default_addend = rcar_gen4_ptp_rate_to_increment(rate);
 	iowrite32(ptp_priv->default_addend, ptp_priv->addr + ptp_priv->offs->increment);
 	ptp_priv->clock = ptp_clock_register(&ptp_priv->info, NULL);
 	if (IS_ERR(ptp_priv->clock))
@@ -159,6 +176,7 @@ int rcar_gen4_ptp_register(struct rcar_gen4_ptp_private *ptp_priv,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(rcar_gen4_ptp_register);
 
 int rcar_gen4_ptp_unregister(struct rcar_gen4_ptp_private *ptp_priv)
 {
@@ -166,6 +184,7 @@ int rcar_gen4_ptp_unregister(struct rcar_gen4_ptp_private *ptp_priv)
 
 	return ptp_clock_unregister(ptp_priv->clock);
 }
+EXPORT_SYMBOL_GPL(rcar_gen4_ptp_unregister);
 
 struct rcar_gen4_ptp_private *rcar_gen4_ptp_alloc(struct platform_device *pdev)
 {
@@ -179,3 +198,8 @@ struct rcar_gen4_ptp_private *rcar_gen4_ptp_alloc(struct platform_device *pdev)
 
 	return ptp;
 }
+EXPORT_SYMBOL_GPL(rcar_gen4_ptp_alloc);
+
+MODULE_AUTHOR("Yoshihiro Shimoda");
+MODULE_DESCRIPTION("Renesas R-Car Gen4 gPTP driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/ethernet/renesas/rcar_gen4_ptp.h b/drivers/net/ethernet/renesas/rcar_gen4_ptp.h
index b1bbea8d3a52..e22da5acd53d 100644
--- a/drivers/net/ethernet/renesas/rcar_gen4_ptp.h
+++ b/drivers/net/ethernet/renesas/rcar_gen4_ptp.h
@@ -9,13 +9,10 @@
 
 #include <linux/ptp_clock_kernel.h>
 
-#define PTPTIVC_INIT			0x19000000	/* 320MHz */
-#define RCAR_GEN4_PTP_CLOCK_S4		PTPTIVC_INIT
 #define RCAR_GEN4_GPTP_OFFSET_S4	0x00018000
 
-/* for rcar_gen4_ptp_init */
 enum rcar_gen4_ptp_reg_layout {
-	RCAR_GEN4_PTP_REG_LAYOUT_S4
+	RCAR_GEN4_PTP_REG_LAYOUT
 };
 
 /* driver's definitions */
@@ -28,7 +25,7 @@ enum rcar_gen4_ptp_reg_layout {
 
 #define PTPRO				0
 
-enum rcar_gen4_ptp_reg_s4 {
+enum rcar_gen4_ptp_reg {
 	PTPTMEC		= PTPRO + 0x0010,
 	PTPTMDC		= PTPRO + 0x0014,
 	PTPTIVC0	= PTPRO + 0x0020,
@@ -65,7 +62,7 @@ struct rcar_gen4_ptp_private {
 };
 
 int rcar_gen4_ptp_register(struct rcar_gen4_ptp_private *ptp_priv,
-			   enum rcar_gen4_ptp_reg_layout layout, u32 clock);
+			   enum rcar_gen4_ptp_reg_layout layout, u32 rate);
 int rcar_gen4_ptp_unregister(struct rcar_gen4_ptp_private *ptp_priv);
 struct rcar_gen4_ptp_private *rcar_gen4_ptp_alloc(struct platform_device *pdev);
 
diff --git a/drivers/net/ethernet/renesas/rswitch.c b/drivers/net/ethernet/renesas/rswitch.c
index 43a7795d6591..d6089429f654 100644
--- a/drivers/net/ethernet/renesas/rswitch.c
+++ b/drivers/net/ethernet/renesas/rswitch.c
@@ -1828,8 +1828,8 @@ static int rswitch_init(struct rswitch_private *priv)
 
 	rswitch_fwd_init(priv);
 
-	err = rcar_gen4_ptp_register(priv->ptp_priv, RCAR_GEN4_PTP_REG_LAYOUT_S4,
-				     RCAR_GEN4_PTP_CLOCK_S4);
+	err = rcar_gen4_ptp_register(priv->ptp_priv, RCAR_GEN4_PTP_REG_LAYOUT,
+				     clk_get_rate(priv->clk));
 	if (err < 0)
 		goto err_ptp_register;