Merge https://source.denx.de/u-boot/custodians/u-boot-usbWIP/28Nov2022

- DWC3 fixes / improvements

4 files changed, 97 insertions, 1 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index b592a48..49f6a19 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -14,6 +14,7 @@
  */
 
 #include <common.h>
+#include <clk.h>
 #include <cpu_func.h>
 #include <malloc.h>
 #include <dwc3-uboot.h>
@@ -28,6 +29,8 @@
 #include <generic-phy.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
+#include <linux/bitfield.h>
+#include <linux/math64.h>
 
 #include "core.h"
 #include "gadget.h"
@@ -35,6 +38,8 @@
 
 #include "linux-compat.h"
 
+#define NSEC_PER_SEC	1000000000L
+
 static LIST_HEAD(dwc3_list);
 /* -------------------------------------------------------------------------- */
 
@@ -115,6 +120,73 @@ static void dwc3_frame_length_adjustment(struct dwc3 *dwc, u32 fladj)
 }
 
 /**
+ * dwc3_ref_clk_period - Reference clock period configuration
+ *		Default reference clock period depends on hardware
+ *		configuration. For systems with reference clock that differs
+ *		from the default, this will set clock period in DWC3_GUCTL
+ *		register.
+ * @dwc: Pointer to our controller context structure
+ * @ref_clk_per: reference clock period in ns
+ */
+static void dwc3_ref_clk_period(struct dwc3 *dwc)
+{
+	unsigned long period;
+	unsigned long fladj;
+	unsigned long decr;
+	unsigned long rate;
+	u32 reg;
+
+	if (dwc->ref_clk) {
+		rate = clk_get_rate(dwc->ref_clk);
+		if (!rate)
+			return;
+		period = NSEC_PER_SEC / rate;
+	} else {
+		return;
+	}
+
+	reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
+	reg &= ~DWC3_GUCTL_REFCLKPER_MASK;
+	reg |=  FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, period);
+	dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
+
+	if (dwc->revision <= DWC3_REVISION_250A)
+		return;
+
+	/*
+	 * The calculation below is
+	 *
+	 * 125000 * (NSEC_PER_SEC / (rate * period) - 1)
+	 *
+	 * but rearranged for fixed-point arithmetic. The division must be
+	 * 64-bit because 125000 * NSEC_PER_SEC doesn't fit in 32 bits (and
+	 * neither does rate * period).
+	 *
+	 * Note that rate * period ~= NSEC_PER_SECOND, minus the number of
+	 * nanoseconds of error caused by the truncation which happened during
+	 * the division when calculating rate or period (whichever one was
+	 * derived from the other). We first calculate the relative error, then
+	 * scale it to units of 8 ppm.
+	 */
+	fladj = div64_u64(125000ULL * NSEC_PER_SEC, (u64)rate * period);
+	fladj -= 125000;
+
+	/*
+	 * The documented 240MHz constant is scaled by 2 to get PLS1 as well.
+	 */
+	decr = 480000000 / rate;
+
+	reg = dwc3_readl(dwc->regs, DWC3_GFLADJ);
+	reg &= ~DWC3_GFLADJ_REFCLK_FLADJ_MASK
+	    &  ~DWC3_GFLADJ_240MHZDECR
+	    &  ~DWC3_GFLADJ_240MHZDECR_PLS1;
+	reg |= FIELD_PREP(DWC3_GFLADJ_REFCLK_FLADJ_MASK, fladj)
+	    |  FIELD_PREP(DWC3_GFLADJ_240MHZDECR, decr >> 1)
+	    |  FIELD_PREP(DWC3_GFLADJ_240MHZDECR_PLS1, decr & 1);
+	dwc3_writel(dwc->regs, DWC3_GFLADJ, reg);
+}
+
+/**
  * dwc3_free_one_event_buffer - Frees one event buffer
  * @dwc: Pointer to our controller context structure
  * @evt: Pointer to event buffer to be freed
@@ -640,6 +712,9 @@ static int dwc3_core_init(struct dwc3 *dwc)
 	/* Adjust Frame Length */
 	dwc3_frame_length_adjustment(dwc, dwc->fladj);
 
+	/* Adjust Reference Clock Period */
+	dwc3_ref_clk_period(dwc);
+
 	dwc3_set_incr_burst_type(dwc);
 
 	return 0;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index d7cce3a..532746d 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -248,6 +248,13 @@
 /* Global Frame Length Adjustment Register */
 #define DWC3_GFLADJ_30MHZ_SDBND_SEL		(1 << 7)
 #define DWC3_GFLADJ_30MHZ_MASK			0x3f
+#define DWC3_GFLADJ_REFCLK_FLADJ_MASK		GENMASK(21, 8)
+#define DWC3_GFLADJ_240MHZDECR			GENMASK(30, 24)
+#define DWC3_GFLADJ_240MHZDECR_PLS1		BIT(31)
+
+/* Global User Control Register*/
+#define DWC3_GUCTL_REFCLKPER_MASK		0xffc00000
+#define DWC3_GUCTL_REFCLKPER_SEL		22
 
 /* Device Configuration Register */
 #define DWC3_DCFG_DEVADDR(addr)	((addr) << 3)
@@ -668,8 +675,10 @@ struct dwc3_scratchpad_array {
  * @event_buffer_list: a list of event buffers
  * @gadget: device side representation of the peripheral controller
  * @gadget_driver: pointer to the gadget driver
+ * @ref_clk: reference clock
  * @regs: base address for our registers
  * @regs_size: address space size
+ * @ref_clk_per: reference clock period configuration
  * @nr_scratch: number of scratch buffers
  * @num_event_buffers: calculated number of event buffers
  * @u1u2: only used on revisions <1.83a for workaround
@@ -766,6 +775,8 @@ struct dwc3 {
 	struct usb_gadget	gadget;
 	struct usb_gadget_driver *gadget_driver;
 
+	struct clk		*ref_clk;
+
 	void __iomem		*regs;
 	size_t			regs_size;
 
@@ -829,6 +840,7 @@ struct dwc3 {
 	u8			lpm_nyet_threshold;
 	u8			hird_threshold;
 	u32			fladj;
+	u32			ref_clk_per;
 	u8			incrx_mode;
 	u32			incrx_size;
 
diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
index 466b25a..7896671 100644
--- a/drivers/usb/dwc3/dwc3-generic.c
+++ b/drivers/usb/dwc3/dwc3-generic.c
@@ -59,12 +59,21 @@ static int dwc3_generic_probe(struct udevice *dev,
 	struct dwc3_generic_plat *plat = dev_get_plat(dev);
 	struct dwc3 *dwc3 = &priv->dwc3;
 	struct dwc3_glue_data *glue = dev_get_plat(dev->parent);
+	int __maybe_unused index;
+	ofnode __maybe_unused node;
 
 	dwc3->dev = dev;
 	dwc3->maximum_speed = plat->maximum_speed;
 	dwc3->dr_mode = plat->dr_mode;
 #if CONFIG_IS_ENABLED(OF_CONTROL)
 	dwc3_of_parse(dwc3);
+
+	node = dev_ofnode(dev->parent);
+	index = ofnode_stringlist_search(node, "clock-names", "ref");
+	if (index < 0)
+		index = ofnode_stringlist_search(node, "clock-names", "ref_clk");
+	if (index >= 0)
+		dwc3->ref_clk = &glue->clks.clks[index];
 #endif
 
 	/*
diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
index 27e2fc6..060f344 100644
--- a/drivers/usb/host/usb-uclass.c
+++ b/drivers/usb/host/usb-uclass.c
@@ -557,7 +557,7 @@ static int usb_find_and_bind_driver(struct udevice *parent,
 	struct usb_driver_entry *start, *entry;
 	int n_ents;
 	int ret;
-	char name[30], *str;
+	char name[34], *str;
 	ofnode node = usb_get_ofnode(parent, port);
 
 	*devp = NULL;