diff options
| author | Bartlomiej Zolnierkiewicz <[email protected]> | 2018-09-26 15:54:31 +0200 |
|---|---|---|
| committer | Bartlomiej Zolnierkiewicz <[email protected]> | 2018-09-26 15:54:31 +0200 |
| commit | aaccf3c97418f169afdbb5855e9cbcbda34e90fd (patch) | |
| tree | 5d4207e67958bdbc23288cf30178692f5534e1a0 /drivers/clk/tegra/clk-utils.c | |
| parent | f39684524b391c5a7ed0ac44db4fec3357af1c5d (diff) | |
| parent | 6bf4ca7fbc85d80446ac01c0d1d77db4d91a6d84 (diff) | |
Merge tag 'v4.19-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next
Sync with upstream (which now contains fbdev-v4.19 changes) to
prepare a base for fbdev-v4.20 changes.
Diffstat (limited to 'drivers/clk/tegra/clk-utils.c')
| -rw-r--r-- | drivers/clk/tegra/clk-utils.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-utils.c b/drivers/clk/tegra/clk-utils.c new file mode 100644 index 000000000000..1a5daae4e501 --- /dev/null +++ b/drivers/clk/tegra/clk-utils.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018, NVIDIA CORPORATION. All rights reserved. + */ + +#include <asm/div64.h> + +#include "clk.h" + +#define div_mask(w) ((1 << (w)) - 1) + +int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width, + u8 frac_width, u8 flags) +{ + u64 divider_ux1 = parent_rate; + int mul; + + if (!rate) + return 0; + + mul = 1 << frac_width; + + if (!(flags & TEGRA_DIVIDER_INT)) + divider_ux1 *= mul; + + if (flags & TEGRA_DIVIDER_ROUND_UP) + divider_ux1 += rate - 1; + + do_div(divider_ux1, rate); + + if (flags & TEGRA_DIVIDER_INT) + divider_ux1 *= mul; + + if (divider_ux1 < mul) + return 0; + + divider_ux1 -= mul; + + if (divider_ux1 > div_mask(width)) + return div_mask(width); + + return divider_ux1; +} |