diff options
| author | Yuval Adam <_@yuv.al> | 2017-08-30 08:25:59 +0000 |
|---|---|---|
| committer | Yuval Adam <_@yuv.al> | 2017-08-30 08:25:59 +0000 |
| commit | 8e4bff4cab0ddac6060645b0715210484d02ff40 (patch) | |
| tree | 3a5c3024371a04692a3a6d9974d001cdff8ebf84 /arch/arm/mach-omap2/clock36xx.c | |
Diffstat (limited to 'arch/arm/mach-omap2/clock36xx.c')
| -rw-r--r-- | arch/arm/mach-omap2/clock36xx.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clock36xx.c b/arch/arm/mach-omap2/clock36xx.c new file mode 100644 index 00000000..bbd6a3f7 --- /dev/null +++ b/arch/arm/mach-omap2/clock36xx.c @@ -0,0 +1,68 @@ +/* + * OMAP36xx-specific clkops + * + * Copyright (C) 2010 Texas Instruments, Inc. + * Copyright (C) 2010 Nokia Corporation + * + * Mike Turquette + * Vijaykumar GN + * Paul Walmsley + * + * Parts of this code are based on code written by + * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu, + * Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/io.h> + +#include "clock.h" +#include "clock36xx.h" +#define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw) + +/** + * omap36xx_pwrdn_clk_enable_with_hsdiv_restore - enable clocks suffering + * from HSDivider PWRDN problem Implements Errata ID: i556. + * @clk: DPLL output struct clk + * + * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck, + * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset + * valueafter their respective PWRDN bits are set. Any dummy write + * (Any other value different from the Read value) to the + * corresponding CM_CLKSEL register will refresh the dividers. + */ +int omap36xx_pwrdn_clk_enable_with_hsdiv_restore(struct clk_hw *clk) +{ + struct clk_divider *parent; + struct clk_hw *parent_hw; + u32 dummy_v, orig_v; + int ret; + + /* Clear PWRDN bit of HSDIVIDER */ + ret = omap2_dflt_clk_enable(clk); + + parent_hw = __clk_get_hw(__clk_get_parent(clk->clk)); + parent = to_clk_divider(parent_hw); + + /* Restore the dividers */ + if (!ret) { + orig_v = __raw_readl(parent->reg); + dummy_v = orig_v; + + /* Write any other value different from the Read value */ + dummy_v ^= (1 << parent->shift); + __raw_writel(dummy_v, parent->reg); + + /* Write the original divider */ + __raw_writel(orig_v, parent->reg); + } + + return ret; +} |
