usb: dwc3: dwc3-octeon: Verify clock divider

Although valid USB clock divider will be calculated for all valid
Octeon core frequencies, make code formally correct limiting
divider not to be greater that 7 so it fits into H_CLKDIV_SEL
field.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Closes: https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20230808/testrun/18882876/suite/build/test/gcc-8-cavium_octeon_defconfig/log
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/ZNIM7tlBNdHFzXZG@lenoch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ladislav Michl 2023-08-08 11:37:50 +02:00 committed by Greg Kroah-Hartman
parent ff33299ec8
commit fb57f829be
1 changed files with 6 additions and 2 deletions

View File

@ -251,11 +251,11 @@ static int dwc3_octeon_get_divider(void)
while (div < ARRAY_SIZE(clk_div)) { while (div < ARRAY_SIZE(clk_div)) {
uint64_t rate = octeon_get_io_clock_rate() / clk_div[div]; uint64_t rate = octeon_get_io_clock_rate() / clk_div[div];
if (rate <= 300000000 && rate >= 150000000) if (rate <= 300000000 && rate >= 150000000)
break; return div;
div++; div++;
} }
return div; return -EINVAL;
} }
static int dwc3_octeon_setup(struct dwc3_octeon *octeon, static int dwc3_octeon_setup(struct dwc3_octeon *octeon,
@ -289,6 +289,10 @@ static int dwc3_octeon_setup(struct dwc3_octeon *octeon,
/* Step 4b: Select controller clock frequency. */ /* Step 4b: Select controller clock frequency. */
div = dwc3_octeon_get_divider(); div = dwc3_octeon_get_divider();
if (div < 0) {
dev_err(dev, "clock divider invalid\n");
return div;
}
val = dwc3_octeon_readq(uctl_ctl_reg); val = dwc3_octeon_readq(uctl_ctl_reg);
val &= ~USBDRD_UCTL_CTL_H_CLKDIV_SEL; val &= ~USBDRD_UCTL_CTL_H_CLKDIV_SEL;
val |= FIELD_PREP(USBDRD_UCTL_CTL_H_CLKDIV_SEL, div); val |= FIELD_PREP(USBDRD_UCTL_CTL_H_CLKDIV_SEL, div);