From 16c90f020034d3cd38b3dab280001e728e6b19e5 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Tue, 27 Jan 2009 19:12:47 -0700 Subject: [ARM] OMAP2/3: Add non-CORE DPLL rate set code and M, N programming Add non-CORE DPLL rate set code and M,N programming for OMAP3. Connect it to OMAP34xx DPLLs 1, 2, 4, 5 via the clock framework. You may see some warnings on rate sets from the freqsel code. The table that TI presented in the 3430 TRM Rev F does not cover Fint < 750000, which definitely occurs in practice. However, the lack of this freqsel case does not appear to impair the DPLL rate change. linux-omap source commit is 689fe67c6d1ad8f52f7f7b139a3274b79bf3e784. Signed-off-by: Paul Walmsley Signed-off-by: Tony Lindgren Signed-off-by: Russell King --- arch/arm/mach-omap2/clock34xx.c | 137 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 136 insertions(+), 1 deletion(-) (limited to 'arch/arm/mach-omap2/clock34xx.c') diff --git a/arch/arm/mach-omap2/clock34xx.c b/arch/arm/mach-omap2/clock34xx.c index 245a7b9b560c..943ac63fc6f8 100644 --- a/arch/arm/mach-omap2/clock34xx.c +++ b/arch/arm/mach-omap2/clock34xx.c @@ -340,6 +340,42 @@ static int _omap3_wait_dpll_status(struct clk *clk, u8 state) return ret; } +/* From 3430 TRM ES2 4.7.6.2 */ +static u16 _omap3_dpll_compute_freqsel(struct clk *clk, u8 n) +{ + unsigned long fint; + u16 f = 0; + + fint = clk->parent->rate / (n + 1); + + pr_debug("clock: fint is %lu\n", fint); + + if (fint >= 750000 && fint <= 1000000) + f = 0x3; + else if (fint > 1000000 && fint <= 1250000) + f = 0x4; + else if (fint > 1250000 && fint <= 1500000) + f = 0x5; + else if (fint > 1500000 && fint <= 1750000) + f = 0x6; + else if (fint > 1750000 && fint <= 2100000) + f = 0x7; + else if (fint > 7500000 && fint <= 10000000) + f = 0xB; + else if (fint > 10000000 && fint <= 12500000) + f = 0xC; + else if (fint > 12500000 && fint <= 15000000) + f = 0xD; + else if (fint > 15000000 && fint <= 17500000) + f = 0xE; + else if (fint > 17500000 && fint <= 21000000) + f = 0xF; + else + pr_debug("clock: unknown freqsel setting for %d\n", n); + + return f; +} + /* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */ /* @@ -476,7 +512,7 @@ static int omap3_noncore_dpll_enable(struct clk *clk) if (clk == &dpll3_ck) return -EINVAL; - if (clk->parent->rate == clk_get_rate(clk)) + if (clk->parent->rate == omap2_get_dpll_rate(clk)) r = _omap3_noncore_dpll_bypass(clk); else r = _omap3_noncore_dpll_lock(clk); @@ -506,11 +542,110 @@ static void omap3_noncore_dpll_disable(struct clk *clk) _omap3_noncore_dpll_stop(clk); } + +/* Non-CORE DPLL rate set code */ + +/* + * omap3_noncore_dpll_program - set non-core DPLL M,N values directly + * @clk: struct clk * of DPLL to set + * @m: DPLL multiplier to set + * @n: DPLL divider to set + * @freqsel: FREQSEL value to set + * + * Program the DPLL with the supplied M, N values, and wait for the DPLL to + * lock.. Returns -EINVAL upon error, or 0 upon success. + */ +static int omap3_noncore_dpll_program(struct clk *clk, u16 m, u8 n, u16 freqsel) +{ + struct dpll_data *dd = clk->dpll_data; + u32 v; + + /* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */ + _omap3_noncore_dpll_bypass(clk); + + v = __raw_readl(dd->mult_div1_reg); + v &= ~(dd->mult_mask | dd->div1_mask); + + /* Set mult (M), div1 (N), freqsel */ + v |= m << __ffs(dd->mult_mask); + v |= n << __ffs(dd->div1_mask); + v |= freqsel << __ffs(dd->freqsel_mask); + + __raw_writel(v, dd->mult_div1_reg); + + /* We let the clock framework set the other output dividers later */ + + /* REVISIT: Set ramp-up delay? */ + + _omap3_noncore_dpll_lock(clk); + + return 0; +} + +/** + * omap3_noncore_dpll_set_rate - set non-core DPLL rate + * @clk: struct clk * of DPLL to set + * @rate: rounded target rate + * + * Program the DPLL with the rounded target rate. Returns -EINVAL upon + * error, or 0 upon success. + */ +static int omap3_noncore_dpll_set_rate(struct clk *clk, unsigned long rate) +{ + u16 freqsel; + struct dpll_data *dd; + + if (!clk || !rate) + return -EINVAL; + + dd = clk->dpll_data; + if (!dd) + return -EINVAL; + + if (rate == omap2_get_dpll_rate(clk)) + return 0; + + if (dd->last_rounded_rate != rate) + omap2_dpll_round_rate(clk, rate); + + if (dd->last_rounded_rate == 0) + return -EINVAL; + + freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n); + if (!freqsel) + WARN_ON(1); + + omap3_noncore_dpll_program(clk, dd->last_rounded_m, dd->last_rounded_n, + freqsel); + + omap3_dpll_recalc(clk); + + return 0; +} + +static int omap3_dpll4_set_rate(struct clk *clk, unsigned long rate) +{ + /* + * According to the 12-5 CDP code from TI, "Limitation 2.5" + * on 3430ES1 prevents us from changing DPLL multipliers or dividers + * on DPLL4. + */ + if (omap_rev() == OMAP3430_REV_ES1_0) { + printk(KERN_ERR "clock: DPLL4 cannot change rate due to " + "silicon 'Limitation 2.5' on 3430ES1.\n"); + return -EINVAL; + } + return omap3_noncore_dpll_set_rate(clk, rate); +} + static const struct clkops clkops_noncore_dpll_ops = { .enable = &omap3_noncore_dpll_enable, .disable = &omap3_noncore_dpll_disable, }; +/* DPLL autoidle read/set code */ + + /** * omap3_dpll_autoidle_read - read a DPLL's autoidle bits * @clk: struct clk * of the DPLL to read -- cgit v1.2.3