Am Mittwoch, den 30.10.2013, 09:41 -0600 schrieb Stephen Warren: > On 10/29/2013 06:41 PM, Peter De Schrijver wrote: > > Use pll_ref instead of pll_re_vco as the pll_e parent on Tegra114 and > > Tegra124. Also add a pll_ref table entry for pll_e for Tegra114. > > Why? What benefit does this give, or what bug does this fix? > > > diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c > > > val_aux = pll_readl(pll_params->aux_reg, pll); > > > > if (val & PLL_BASE_ENABLE) { > > - if (!(val_aux & PLLE_AUX_PLLRE_SEL)) > > + if ((val_aux & PLLE_AUX_PLLRE_SEL) || (val_aux & val_aux)) > > Isn't "|| (val_aux & val_aux)" always true, at least if the value is > non-zero? Either this should be simply "|| val_aux", or one of those two > "val_aux" is the wrong thing. > > > WARN(1, "pll_e enabled with unsupported parent %s\n", > > - (val & PLLE_AUX_PLLP_SEL) ? "pllp_out0" : "pll_ref"); > > + (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" : > > + "pll_re_vco"); > > } else { > > - val_aux |= PLLE_AUX_PLLRE_SEL; > > + val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL); > > pll_writel(val, pll_params->aux_reg, pll); > > } > > > diff --git a/drivers/clk/tegra/clk-tegra114.c b/drivers/clk/tegra/clk-tegra114.c > > > @@ -560,6 +560,7 @@ static struct tegra_clk_pll_freq_table pll_e_freq_table[] = { > > /* PLLE special case: use cpcon field to store cml divider value */ > > {336000000, 100000000, 100, 21, 16, 11}, > > {312000000, 100000000, 200, 26, 24, 13}, > > + {12000000, 100000000, 200, 1, 24, 13}, > > Presumably this is because pll_ref is the crystal, which runs at 12MHz. > What if it doesn't; Tegra supports a bunch of other crystal rates. Don't > we need entries for all the other potential crystal rates too? The TRM states that PCIe and thus PLLE are only supported with 12MHz external crystal rate. -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-5076 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html