diff options
Diffstat (limited to 'drivers/clk/rockchip/clk.c')
| -rw-r--r-- | drivers/clk/rockchip/clk.c | 144 |
1 files changed, 129 insertions, 15 deletions
diff --git a/drivers/clk/rockchip/clk.c b/drivers/clk/rockchip/clk.c index be6c7fd8315d..d9a0b5d4d47f 100644 --- a/drivers/clk/rockchip/clk.c +++ b/drivers/clk/rockchip/clk.c @@ -102,22 +102,82 @@ static struct clk *rockchip_clk_register_branch(const char *name, return clk; } +struct rockchip_clk_frac { + struct notifier_block clk_nb; + struct clk_fractional_divider div; + struct clk_gate gate; + + struct clk_mux mux; + const struct clk_ops *mux_ops; + int mux_frac_idx; + + bool rate_change_remuxed; + int rate_change_idx; +}; + +#define to_rockchip_clk_frac_nb(nb) \ + container_of(nb, struct rockchip_clk_frac, clk_nb) + +static int rockchip_clk_frac_notifier_cb(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct clk_notifier_data *ndata = data; + struct rockchip_clk_frac *frac = to_rockchip_clk_frac_nb(nb); + struct clk_mux *frac_mux = &frac->mux; + int ret = 0; + + pr_debug("%s: event %lu, old_rate %lu, new_rate: %lu\n", + __func__, event, ndata->old_rate, ndata->new_rate); + if (event == PRE_RATE_CHANGE) { + frac->rate_change_idx = frac->mux_ops->get_parent(&frac_mux->hw); + if (frac->rate_change_idx != frac->mux_frac_idx) { + frac->mux_ops->set_parent(&frac_mux->hw, frac->mux_frac_idx); + frac->rate_change_remuxed = 1; + } + } else if (event == POST_RATE_CHANGE) { + /* + * The POST_RATE_CHANGE notifier runs directly after the + * divider clock is set in clk_change_rate, so we'll have + * remuxed back to the original parent before clk_change_rate + * reaches the mux itself. + */ + if (frac->rate_change_remuxed) { + frac->mux_ops->set_parent(&frac_mux->hw, frac->rate_change_idx); + frac->rate_change_remuxed = 0; + } + } + + return notifier_from_errno(ret); +} + static struct clk *rockchip_clk_register_frac_branch(const char *name, const char *const *parent_names, u8 num_parents, void __iomem *base, int muxdiv_offset, u8 div_flags, int gate_offset, u8 gate_shift, u8 gate_flags, - unsigned long flags, spinlock_t *lock) + unsigned long flags, struct rockchip_clk_branch *child, + spinlock_t *lock) { + struct rockchip_clk_frac *frac; struct clk *clk; struct clk_gate *gate = NULL; struct clk_fractional_divider *div = NULL; const struct clk_ops *div_ops = NULL, *gate_ops = NULL; - if (gate_offset >= 0) { - gate = kzalloc(sizeof(*gate), GFP_KERNEL); - if (!gate) - return ERR_PTR(-ENOMEM); + if (muxdiv_offset < 0) + return ERR_PTR(-EINVAL); + + if (child && child->branch_type != branch_mux) { + pr_err("%s: fractional child clock for %s can only be a mux\n", + __func__, name); + return ERR_PTR(-EINVAL); + } + frac = kzalloc(sizeof(*frac), GFP_KERNEL); + if (!frac) + return ERR_PTR(-ENOMEM); + + if (gate_offset >= 0) { + gate = &frac->gate; gate->flags = gate_flags; gate->reg = base + gate_offset; gate->bit_idx = gate_shift; @@ -125,13 +185,7 @@ static struct clk *rockchip_clk_register_frac_branch(const char *name, gate_ops = &clk_gate_ops; } - if (muxdiv_offset < 0) - return ERR_PTR(-EINVAL); - - div = kzalloc(sizeof(*div), GFP_KERNEL); - if (!div) - return ERR_PTR(-ENOMEM); - + div = &frac->div; div->flags = div_flags; div->reg = base + muxdiv_offset; div->mshift = 16; @@ -147,7 +201,61 @@ static struct clk *rockchip_clk_register_frac_branch(const char *name, NULL, NULL, &div->hw, div_ops, gate ? &gate->hw : NULL, gate_ops, - flags); + flags | CLK_SET_RATE_UNGATE); + if (IS_ERR(clk)) { + kfree(frac); + return clk; + } + + if (child) { + struct clk_mux *frac_mux = &frac->mux; + struct clk_init_data init; + struct clk *mux_clk; + int i, ret; + + frac->mux_frac_idx = -1; + for (i = 0; i < child->num_parents; i++) { + if (!strcmp(name, child->parent_names[i])) { + pr_debug("%s: found fractional parent in mux at pos %d\n", + __func__, i); + frac->mux_frac_idx = i; + break; + } + } + + frac->mux_ops = &clk_mux_ops; + frac->clk_nb.notifier_call = rockchip_clk_frac_notifier_cb; + + frac_mux->reg = base + child->muxdiv_offset; + frac_mux->shift = child->mux_shift; + frac_mux->mask = BIT(child->mux_width) - 1; + frac_mux->flags = child->mux_flags; + frac_mux->lock = lock; + frac_mux->hw.init = &init; + + init.name = child->name; + init.flags = child->flags | CLK_SET_RATE_PARENT; + init.ops = frac->mux_ops; + init.parent_names = child->parent_names; + init.num_parents = child->num_parents; + + mux_clk = clk_register(NULL, &frac_mux->hw); + if (IS_ERR(mux_clk)) + return clk; + + rockchip_clk_add_lookup(mux_clk, child->id); + + /* notifier on the fraction divider to catch rate changes */ + if (frac->mux_frac_idx >= 0) { + ret = clk_notifier_register(clk, &frac->clk_nb); + if (ret) + pr_err("%s: failed to register clock notifier for %s\n", + __func__, name); + } else { + pr_warn("%s: could not find %s as parent of %s, rate changes may not work\n", + __func__, name, child->name); + } + } return clk; } @@ -251,7 +359,8 @@ void __init rockchip_clk_register_branches( list->parent_names, list->num_parents, reg_base, list->muxdiv_offset, list->div_flags, list->gate_offset, list->gate_shift, - list->gate_flags, flags, &clk_lock); + list->gate_flags, flags, list->child, + &clk_lock); break; case branch_gate: flags |= CLK_SET_RATE_PARENT; @@ -341,9 +450,13 @@ void __init rockchip_clk_protect_critical(const char *const clocks[], } static unsigned int reg_restart; +static void (*cb_restart)(void); static int rockchip_restart_notify(struct notifier_block *this, unsigned long mode, void *cmd) { + if (cb_restart) + cb_restart(); + writel(0xfdb9, reg_base + reg_restart); return NOTIFY_DONE; } @@ -353,11 +466,12 @@ static struct notifier_block rockchip_restart_handler = { .priority = 128, }; -void __init rockchip_register_restart_notifier(unsigned int reg) +void __init rockchip_register_restart_notifier(unsigned int reg, void (*cb)(void)) { int ret; reg_restart = reg; + cb_restart = cb; ret = register_restart_handler(&rockchip_restart_handler); if (ret) pr_err("%s: cannot register restart handler, %d\n", |