usb: dwc3: Calculate REFCLKPER based on reference clock
Instead of using a special property to determine the reference clock
period, use the rate of the reference clock. When we have a legacy
snps,ref-clock-period-ns property and no reference clock, use it
instead. Fractional clocks are not currently supported, and will be
dealt with in the next commit.
[ marek: Ported from Linux kernel commit
5114c3ee24875 ("usb: dwc3: Calculate REFCLKPER based on reference clock") ]
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: Marek Vasut <marex@denx.de> # Port from Linux
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 3004501..ed5d0d1 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>
@@ -126,14 +127,24 @@
*/
static void dwc3_ref_clk_period(struct dwc3 *dwc)
{
+ unsigned long period;
+ unsigned long rate;
u32 reg;
- if (dwc->ref_clk_per == 0)
+ if (dwc->ref_clk) {
+ rate = clk_get_rate(dwc->ref_clk);
+ if (!rate)
+ return;
+ period = NSEC_PER_SEC / rate;
+ } else if (dwc->ref_clk_per) {
+ period = dwc->ref_clk_per;
+ } else {
return;
+ }
reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
reg &= ~DWC3_GUCTL_REFCLKPER_MASK;
- reg |= FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, dwc->ref_clk_per);
+ reg |= FIELD_PREP(DWC3_GUCTL_REFCLKPER_MASK, period);
dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
}