diff options
| -rw-r--r-- | arch/arm/cpu/arm926ejs/mxs/clock.c | 93 | ||||
| -rw-r--r-- | arch/arm/include/asm/arch-mxs/clock.h | 1 |
2 files changed, 94 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/mxs/clock.c b/arch/arm/cpu/arm926ejs/mxs/clock.c index 43e7663..f94107f 100644 --- a/arch/arm/cpu/arm926ejs/mxs/clock.c +++ b/arch/arm/cpu/arm926ejs/mxs/clock.c @@ -325,6 +325,99 @@ void mxs_set_ssp_busclock(unsigned int bus, uint32_t freq) bus, tgtclk, freq); } +void mxs_set_lcdclk(uint32_t freq) +{ + struct mxs_clkctrl_regs *clkctrl_regs = + (struct mxs_clkctrl_regs *)MXS_CLKCTRL_BASE; + uint32_t fp, x, k_rest, k_best, x_best, tk; + int32_t k_best_l = 999, k_best_t = 0, x_best_l = 0xff, x_best_t = 0xff; + + if (freq == 0) + return; + +#if defined(CONFIG_MX23) + writel(CLKCTRL_CLKSEQ_BYPASS_PIX, &clkctrl_regs->hw_clkctrl_clkseq_clr); +#elif defined(CONFIG_MX28) + writel(CLKCTRL_CLKSEQ_BYPASS_DIS_LCDIF, &clkctrl_regs->hw_clkctrl_clkseq_clr); +#endif + + /* + * / 18 \ 1 1 + * freq kHz = | 480000000 Hz * -- | * --- * ------ + * \ x / k 1000 + * + * 480000000 Hz 18 + * ------------ * -- + * freq kHz x + * k = ------------------- + * 1000 + */ + + fp = ((PLL_FREQ_KHZ * 1000) / freq) * 18; + + for (x = 18; x <= 35; x++) { + tk = fp / x; + if ((tk / 1000 == 0) || (tk / 1000 > 255)) + continue; + + k_rest = tk % 1000; + + if (k_rest < (k_best_l % 1000)) { + k_best_l = tk; + x_best_l = x; + } + + if (k_rest > (k_best_t % 1000)) { + k_best_t = tk; + x_best_t = x; + } + } + + if (1000 - (k_best_t % 1000) > (k_best_l % 1000)) { + k_best = k_best_l; + x_best = x_best_l; + } else { + k_best = k_best_t; + x_best = x_best_t; + } + + k_best /= 1000; + +#if defined(CONFIG_MX23) + writeb(CLKCTRL_FRAC_CLKGATE, + &clkctrl_regs->hw_clkctrl_frac0_set[CLKCTRL_FRAC0_PIX]); + writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK), + &clkctrl_regs->hw_clkctrl_frac0[CLKCTRL_FRAC0_PIX]); + writeb(CLKCTRL_FRAC_CLKGATE, + &clkctrl_regs->hw_clkctrl_frac0_clr[CLKCTRL_FRAC0_PIX]); + + writel(CLKCTRL_PIX_CLKGATE, + &clkctrl_regs->hw_clkctrl_pix_set); + clrsetbits_le32(&clkctrl_regs->hw_clkctrl_pix, + CLKCTRL_PIX_DIV_MASK | CLKCTRL_PIX_CLKGATE, + k_best << CLKCTRL_PIX_DIV_OFFSET); + + while (readl(&clkctrl_regs->hw_clkctrl_pix) & CLKCTRL_PIX_BUSY) + ; +#elif defined(CONFIG_MX28) + writeb(CLKCTRL_FRAC_CLKGATE, + &clkctrl_regs->hw_clkctrl_frac1_set[CLKCTRL_FRAC1_PIX]); + writeb(CLKCTRL_FRAC_CLKGATE | (x_best & CLKCTRL_FRAC_FRAC_MASK), + &clkctrl_regs->hw_clkctrl_frac1[CLKCTRL_FRAC1_PIX]); + writeb(CLKCTRL_FRAC_CLKGATE, + &clkctrl_regs->hw_clkctrl_frac1_clr[CLKCTRL_FRAC1_PIX]); + + writel(CLKCTRL_DIS_LCDIF_CLKGATE, + &clkctrl_regs->hw_clkctrl_lcdif_set); + clrsetbits_le32(&clkctrl_regs->hw_clkctrl_lcdif, + CLKCTRL_DIS_LCDIF_DIV_MASK | CLKCTRL_DIS_LCDIF_CLKGATE, + k_best << CLKCTRL_DIS_LCDIF_DIV_OFFSET); + + while (readl(&clkctrl_regs->hw_clkctrl_lcdif) & CLKCTRL_DIS_LCDIF_BUSY) + ; +#endif +} + uint32_t mxc_get_clock(enum mxc_clock clk) { switch (clk) { diff --git a/arch/arm/include/asm/arch-mxs/clock.h b/arch/arm/include/asm/arch-mxs/clock.h index 3f7d3f0..9be53f0 100644 --- a/arch/arm/include/asm/arch-mxs/clock.h +++ b/arch/arm/include/asm/arch-mxs/clock.h @@ -59,6 +59,7 @@ uint32_t mxc_get_clock(enum mxc_clock clk); void mxs_set_ioclk(enum mxs_ioclock io, uint32_t freq); void mxs_set_sspclk(enum mxs_sspclock ssp, uint32_t freq, int xtal); void mxs_set_ssp_busclock(unsigned int bus, uint32_t freq); +void mxs_set_lcdclk(uint32_t freq); /* Compatibility with the FEC Ethernet driver */ #define imx_get_fecclk() mxc_get_clock(MXC_AHB_CLK) |