diff options
author | H. Peter Anvin <hpa@linux.intel.com> | 2014-02-07 11:27:30 -0800 |
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committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-02-07 11:27:30 -0800 |
commit | a3b072cd180c12e8fe0ece9487b9065808327640 (patch) | |
tree | 62b982041be84748852d77cdf6ca5639ef40858f /drivers/clk/ti/autoidle.c | |
parent | 75a1ba5b2c529db60ca49626bcaf0bddf4548438 (diff) | |
parent | 081cd62a010f97b5bc1d2b0cd123c5abc692b68a (diff) |
Merge tag 'efi-urgent' into x86/urgent
* Avoid WARN_ON() when mapping BGRT on Baytrail (EFI 32-bit).
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'drivers/clk/ti/autoidle.c')
-rw-r--r-- | drivers/clk/ti/autoidle.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/clk/ti/autoidle.c b/drivers/clk/ti/autoidle.c new file mode 100644 index 00000000000..8912ff80af3 --- /dev/null +++ b/drivers/clk/ti/autoidle.c @@ -0,0 +1,133 @@ +/* + * TI clock autoidle support + * + * Copyright (C) 2013 Texas Instruments, Inc. + * + * Tero Kristo <t-kristo@ti.com> + * + * 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. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk-provider.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/clk/ti.h> + +struct clk_ti_autoidle { + void __iomem *reg; + u8 shift; + u8 flags; + const char *name; + struct list_head node; +}; + +#define AUTOIDLE_LOW 0x1 + +static LIST_HEAD(autoidle_clks); + +static void ti_allow_autoidle(struct clk_ti_autoidle *clk) +{ + u32 val; + + val = ti_clk_ll_ops->clk_readl(clk->reg); + + if (clk->flags & AUTOIDLE_LOW) + val &= ~(1 << clk->shift); + else + val |= (1 << clk->shift); + + ti_clk_ll_ops->clk_writel(val, clk->reg); +} + +static void ti_deny_autoidle(struct clk_ti_autoidle *clk) +{ + u32 val; + + val = ti_clk_ll_ops->clk_readl(clk->reg); + + if (clk->flags & AUTOIDLE_LOW) + val |= (1 << clk->shift); + else + val &= ~(1 << clk->shift); + + ti_clk_ll_ops->clk_writel(val, clk->reg); +} + +/** + * of_ti_clk_allow_autoidle_all - enable autoidle for all clocks + * + * Enables hardware autoidle for all registered DT clocks, which have + * the feature. + */ +void of_ti_clk_allow_autoidle_all(void) +{ + struct clk_ti_autoidle *c; + + list_for_each_entry(c, &autoidle_clks, node) + ti_allow_autoidle(c); +} + +/** + * of_ti_clk_deny_autoidle_all - disable autoidle for all clocks + * + * Disables hardware autoidle for all registered DT clocks, which have + * the feature. + */ +void of_ti_clk_deny_autoidle_all(void) +{ + struct clk_ti_autoidle *c; + + list_for_each_entry(c, &autoidle_clks, node) + ti_deny_autoidle(c); +} + +/** + * of_ti_clk_autoidle_setup - sets up hardware autoidle for a clock + * @node: pointer to the clock device node + * + * Checks if a clock has hardware autoidle support or not (check + * for presence of 'ti,autoidle-shift' property in the device tree + * node) and sets up the hardware autoidle feature for the clock + * if available. If autoidle is available, the clock is also added + * to the autoidle list for later processing. Returns 0 on success, + * negative error value on failure. + */ +int __init of_ti_clk_autoidle_setup(struct device_node *node) +{ + u32 shift; + struct clk_ti_autoidle *clk; + + /* Check if this clock has autoidle support or not */ + if (of_property_read_u32(node, "ti,autoidle-shift", &shift)) + return 0; + + clk = kzalloc(sizeof(*clk), GFP_KERNEL); + + if (!clk) + return -ENOMEM; + + clk->shift = shift; + clk->name = node->name; + clk->reg = ti_clk_get_reg_addr(node, 0); + + if (!clk->reg) { + kfree(clk); + return -EINVAL; + } + + if (of_property_read_bool(node, "ti,invert-autoidle-bit")) + clk->flags |= AUTOIDLE_LOW; + + list_add(&clk->node, &autoidle_clks); + + return 0; +} |