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| author | Ladislav Michl <ladis@linux-mips.org> | 2023-06-19 22:14:03 +0200 |
|---|---|---|
| committer | Thomas Bogendoerfer <tsbogend@alpha.franken.de> | 2023-06-23 15:06:40 +0200 |
| commit | dc917ea7a2c95545dd41572a5685a95566ff9985 (patch) | |
| tree | a2bd07758b456f3a16e31d3aaf090e9ee94cd15e /arch/mips/cavium-octeon | |
| parent | 2257c6c90e9223e00d0e37ec721c86f45d8ba1d9 (diff) | |
| download | lwn-dc917ea7a2c95545dd41572a5685a95566ff9985.tar.gz lwn-dc917ea7a2c95545dd41572a5685a95566ff9985.zip | |
MIPS: OCTEON: octeon-usb: cleanup divider calculation
Simple self-contained function is easier to review.
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Diffstat (limited to 'arch/mips/cavium-octeon')
| -rw-r--r-- | arch/mips/cavium-octeon/octeon-usb.c | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/arch/mips/cavium-octeon/octeon-usb.c b/arch/mips/cavium-octeon/octeon-usb.c index aaddc874f0ca..2add435ad038 100644 --- a/arch/mips/cavium-octeon/octeon-usb.c +++ b/arch/mips/cavium-octeon/octeon-usb.c @@ -187,12 +187,7 @@ #define USBDRD_UCTL_ECC 0xf0 #define USBDRD_UCTL_SPARE1 0xf8 -#define OCTEON_H_CLKDIV_SEL 8 -#define OCTEON_MIN_H_CLK_RATE 150000000 -#define OCTEON_MAX_H_CLK_RATE 300000000 - static DEFINE_MUTEX(dwc3_octeon_clocks_mutex); -static uint8_t clk_div[OCTEON_H_CLKDIV_SEL] = {1, 2, 4, 6, 8, 16, 24, 32}; #ifdef CONFIG_CAVIUM_OCTEON_SOC #include <asm/octeon/octeon.h> @@ -240,6 +235,21 @@ static inline void dwc3_octeon_writeq(void __iomem *base, uint64_t val) { } static inline void dwc3_octeon_config_gpio(int index, int gpio) { } #endif +static int dwc3_octeon_get_divider(void) +{ + static const uint8_t clk_div[] = { 1, 2, 4, 6, 8, 16, 24, 32 }; + int div = 0; + + while (div < ARRAY_SIZE(clk_div)) { + uint64_t rate = octeon_get_io_clock_rate() / clk_div[div]; + if (rate <= 300000000 && rate >= 150000000) + break; + div++; + } + + return div; +} + static int dwc3_octeon_config_power(struct device *dev, void __iomem *base) { uint32_t gpio_pwr[3]; @@ -284,9 +294,9 @@ static int dwc3_octeon_config_power(struct device *dev, void __iomem *base) static int dwc3_octeon_clocks_start(struct device *dev, void __iomem *base) { - int i, mpll_mul, ref_clk_fsel, ref_clk_sel = 2; + int i, div, mpll_mul, ref_clk_fsel, ref_clk_sel = 2; u32 clock_rate; - u64 div, h_clk_rate, val; + u64 val; void __iomem *uctl_ctl_reg = base + USBDRD_UCTL_CTL; if (dev->of_node) { @@ -363,12 +373,7 @@ static int dwc3_octeon_clocks_start(struct device *dev, void __iomem *base) dwc3_octeon_writeq(uctl_ctl_reg, val); /* Step 4b: Select controller clock frequency. */ - for (div = 0; div < OCTEON_H_CLKDIV_SEL; div++) { - h_clk_rate = octeon_get_io_clock_rate() / clk_div[div]; - if (h_clk_rate <= OCTEON_MAX_H_CLK_RATE && - h_clk_rate >= OCTEON_MIN_H_CLK_RATE) - break; - } + div = dwc3_octeon_get_divider(); val = dwc3_octeon_readq(uctl_ctl_reg); val &= ~USBDRD_UCTL_CTL_H_CLKDIV_SEL; val |= FIELD_PREP(USBDRD_UCTL_CTL_H_CLKDIV_SEL, div); |