diff options
author | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-11 10:41:07 +0300 |
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committer | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-13 08:17:18 +0300 |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/clk/imx/clk-pfd.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/clk/imx/clk-pfd.c')
-rw-r--r-- | kernel/drivers/clk/imx/clk-pfd.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/kernel/drivers/clk/imx/clk-pfd.c b/kernel/drivers/clk/imx/clk-pfd.c new file mode 100644 index 000000000..04a3e78ea --- /dev/null +++ b/kernel/drivers/clk/imx/clk-pfd.c @@ -0,0 +1,157 @@ +/* + * Copyright 2012 Freescale Semiconductor, Inc. + * Copyright 2012 Linaro Ltd. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/err.h> +#include "clk.h" + +/** + * struct clk_pfd - IMX PFD clock + * @clk_hw: clock source + * @reg: PFD register address + * @idx: the index of PFD encoded in the register + * + * PFD clock found on i.MX6 series. Each register for PFD has 4 clk_pfd + * data encoded, and member idx is used to specify the one. And each + * register has SET, CLR and TOG registers at offset 0x4 0x8 and 0xc. + */ +struct clk_pfd { + struct clk_hw hw; + void __iomem *reg; + u8 idx; +}; + +#define to_clk_pfd(_hw) container_of(_hw, struct clk_pfd, hw) + +#define SET 0x4 +#define CLR 0x8 +#define OTG 0xc + +static int clk_pfd_enable(struct clk_hw *hw) +{ + struct clk_pfd *pfd = to_clk_pfd(hw); + + writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + CLR); + + return 0; +} + +static void clk_pfd_disable(struct clk_hw *hw) +{ + struct clk_pfd *pfd = to_clk_pfd(hw); + + writel_relaxed(1 << ((pfd->idx + 1) * 8 - 1), pfd->reg + SET); +} + +static unsigned long clk_pfd_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_pfd *pfd = to_clk_pfd(hw); + u64 tmp = parent_rate; + u8 frac = (readl_relaxed(pfd->reg) >> (pfd->idx * 8)) & 0x3f; + + tmp *= 18; + do_div(tmp, frac); + + return tmp; +} + +static long clk_pfd_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + u64 tmp = *prate; + u8 frac; + + tmp = tmp * 18 + rate / 2; + do_div(tmp, rate); + frac = tmp; + if (frac < 12) + frac = 12; + else if (frac > 35) + frac = 35; + tmp = *prate; + tmp *= 18; + do_div(tmp, frac); + + return tmp; +} + +static int clk_pfd_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_pfd *pfd = to_clk_pfd(hw); + u64 tmp = parent_rate; + u8 frac; + + tmp = tmp * 18 + rate / 2; + do_div(tmp, rate); + frac = tmp; + if (frac < 12) + frac = 12; + else if (frac > 35) + frac = 35; + + writel_relaxed(0x3f << (pfd->idx * 8), pfd->reg + CLR); + writel_relaxed(frac << (pfd->idx * 8), pfd->reg + SET); + + return 0; +} + +static int clk_pfd_is_enabled(struct clk_hw *hw) +{ + struct clk_pfd *pfd = to_clk_pfd(hw); + + if (readl_relaxed(pfd->reg) & (1 << ((pfd->idx + 1) * 8 - 1))) + return 0; + + return 1; +} + +static const struct clk_ops clk_pfd_ops = { + .enable = clk_pfd_enable, + .disable = clk_pfd_disable, + .recalc_rate = clk_pfd_recalc_rate, + .round_rate = clk_pfd_round_rate, + .set_rate = clk_pfd_set_rate, + .is_enabled = clk_pfd_is_enabled, +}; + +struct clk *imx_clk_pfd(const char *name, const char *parent_name, + void __iomem *reg, u8 idx) +{ + struct clk_pfd *pfd; + struct clk *clk; + struct clk_init_data init; + + pfd = kzalloc(sizeof(*pfd), GFP_KERNEL); + if (!pfd) + return ERR_PTR(-ENOMEM); + + pfd->reg = reg; + pfd->idx = idx; + + init.name = name; + init.ops = &clk_pfd_ops; + init.flags = 0; + init.parent_names = &parent_name; + init.num_parents = 1; + + pfd->hw.init = &init; + + clk = clk_register(NULL, &pfd->hw); + if (IS_ERR(clk)) + kfree(pfd); + + return clk; +} |