diff options
Diffstat (limited to 'drivers/clk/meson/meson8b.c')
| -rw-r--r-- | drivers/clk/meson/meson8b.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c index b07a92ed7de3..c06a1a7faa4c 100644 --- a/drivers/clk/meson/meson8b.c +++ b/drivers/clk/meson/meson8b.c @@ -1116,6 +1116,53 @@ static const struct reset_control_ops meson8b_clk_reset_ops = { .deassert = meson8b_clk_reset_deassert, }; +struct meson8b_nb_data { + struct notifier_block nb; + struct clk_hw_onecell_data *onecell_data; +}; + +static int meson8b_cpu_clk_notifier_cb(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct meson8b_nb_data *nb_data = + container_of(nb, struct meson8b_nb_data, nb); + struct clk_hw **hws = nb_data->onecell_data->hws; + struct clk_hw *cpu_clk_hw, *parent_clk_hw; + struct clk *cpu_clk, *parent_clk; + int ret; + + switch (event) { + case PRE_RATE_CHANGE: + parent_clk_hw = hws[CLKID_XTAL]; + break; + + case POST_RATE_CHANGE: + parent_clk_hw = hws[CLKID_CPU_SCALE_OUT_SEL]; + break; + + default: + return NOTIFY_DONE; + } + + cpu_clk_hw = hws[CLKID_CPUCLK]; + cpu_clk = __clk_lookup(clk_hw_get_name(cpu_clk_hw)); + + parent_clk = __clk_lookup(clk_hw_get_name(parent_clk_hw)); + + ret = clk_set_parent(cpu_clk, parent_clk); + if (ret) + return notifier_from_errno(ret); + + udelay(100); + + return NOTIFY_OK; +} + +static struct meson8b_nb_data meson8b_cpu_nb_data = { + .nb.notifier_call = meson8b_cpu_clk_notifier_cb, + .onecell_data = &meson8b_hw_onecell_data, +}; + static const struct regmap_config clkc_regmap_config = { .reg_bits = 32, .val_bits = 32, @@ -1125,6 +1172,8 @@ static const struct regmap_config clkc_regmap_config = { static void __init meson8b_clkc_init(struct device_node *np) { struct meson8b_clk_reset *rstc; + const char *notifier_clk_name; + struct clk *notifier_clk; void __iomem *clk_base; struct regmap *map; int i, ret; @@ -1179,6 +1228,20 @@ static void __init meson8b_clkc_init(struct device_node *np) return; } + /* + * FIXME we shouldn't program the muxes in notifier handlers. The + * tricky programming sequence will be handled by the forthcoming + * coordinated clock rates mechanism once that feature is released. + */ + notifier_clk_name = clk_hw_get_name(&meson8b_cpu_scale_out_sel.hw); + notifier_clk = __clk_lookup(notifier_clk_name); + ret = clk_notifier_register(notifier_clk, &meson8b_cpu_nb_data.nb); + if (ret) { + pr_err("%s: failed to register the CPU clock notifier\n", + __func__); + return; + } + ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, &meson8b_hw_onecell_data); if (ret) |