diff options
Diffstat (limited to 'drivers/clk/renesas/rcar-cpg-lib.c')
| -rw-r--r-- | drivers/clk/renesas/rcar-cpg-lib.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/clk/renesas/rcar-cpg-lib.c b/drivers/clk/renesas/rcar-cpg-lib.c new file mode 100644 index 000000000..5a15f8788 --- /dev/null +++ b/drivers/clk/renesas/rcar-cpg-lib.c @@ -0,0 +1,209 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * R-Car Gen3 Clock Pulse Generator Library + * + * Copyright (C) 2015-2018 Glider bvba + * Copyright (C) 2019 Renesas Electronics Corp. + * + * Based on clk-rcar-gen3.c + * + * Copyright (C) 2015 Renesas Electronics Corp. + */ + +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/sys_soc.h> + +#include "rcar-cpg-lib.h" + +spinlock_t cpg_lock; + +void cpg_reg_modify(void __iomem *reg, u32 clear, u32 set) +{ + unsigned long flags; + u32 val; + + spin_lock_irqsave(&cpg_lock, flags); + val = readl(reg); + val &= ~clear; + val |= set; + writel(val, reg); + spin_unlock_irqrestore(&cpg_lock, flags); +}; + +static int cpg_simple_notifier_call(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct cpg_simple_notifier *csn = + container_of(nb, struct cpg_simple_notifier, nb); + + switch (action) { + case PM_EVENT_SUSPEND: + csn->saved = readl(csn->reg); + return NOTIFY_OK; + + case PM_EVENT_RESUME: + writel(csn->saved, csn->reg); + return NOTIFY_OK; + } + return NOTIFY_DONE; +} + +void cpg_simple_notifier_register(struct raw_notifier_head *notifiers, + struct cpg_simple_notifier *csn) +{ + csn->nb.notifier_call = cpg_simple_notifier_call; + raw_notifier_chain_register(notifiers, &csn->nb); +} + +/* + * SDn Clock + */ + +#define SDnSRCFC_SHIFT 2 +#define STPnHCK BIT(9 - SDnSRCFC_SHIFT) + +static const struct clk_div_table cpg_sdh_div_table[] = { + /* + * These values are recommended by the datasheet. Because they come + * first, Linux will only use these. + */ + { 0, 1 }, { 1, 2 }, { STPnHCK | 2, 4 }, { STPnHCK | 3, 8 }, + { STPnHCK | 4, 16 }, + /* + * These values are not recommended because STPnHCK is wrong. But they + * have been seen because of broken firmware. So, we support reading + * them but Linux will sanitize them when initializing through + * recalc_rate. + */ + { STPnHCK | 0, 1 }, { STPnHCK | 1, 2 }, { 2, 4 }, { 3, 8 }, { 4, 16 }, + /* Sentinel */ + { 0, 0 } +}; + +struct clk * __init cpg_sdh_clk_register(const char *name, + void __iomem *sdnckcr, const char *parent_name, + struct raw_notifier_head *notifiers) +{ + struct cpg_simple_notifier *csn; + struct clk *clk; + + csn = kzalloc(sizeof(*csn), GFP_KERNEL); + if (!csn) + return ERR_PTR(-ENOMEM); + + csn->reg = sdnckcr; + + clk = clk_register_divider_table(NULL, name, parent_name, 0, sdnckcr, + SDnSRCFC_SHIFT, 8, 0, cpg_sdh_div_table, + &cpg_lock); + if (IS_ERR(clk)) { + kfree(csn); + return clk; + } + + cpg_simple_notifier_register(notifiers, csn); + return clk; +} + +static const struct clk_div_table cpg_sd_div_table[] = { + { 0, 2 }, { 1, 4 }, { 0, 0 }, +}; + +struct clk * __init cpg_sd_clk_register(const char *name, + void __iomem *sdnckcr, const char *parent_name) +{ + return clk_register_divider_table(NULL, name, parent_name, 0, sdnckcr, + 0, 2, 0, cpg_sd_div_table, &cpg_lock); +} + +struct rpc_clock { + struct clk_divider div; + struct clk_gate gate; + /* + * One notifier covers both RPC and RPCD2 clocks as they are both + * controlled by the same RPCCKCR register... + */ + struct cpg_simple_notifier csn; +}; + +static const struct clk_div_table cpg_rpc_div_table[] = { + { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 }, { 0, 0 }, +}; + +struct clk * __init cpg_rpc_clk_register(const char *name, + void __iomem *rpcckcr, const char *parent_name, + struct raw_notifier_head *notifiers) +{ + struct rpc_clock *rpc; + struct clk *clk; + + rpc = kzalloc(sizeof(*rpc), GFP_KERNEL); + if (!rpc) + return ERR_PTR(-ENOMEM); + + rpc->div.reg = rpcckcr; + rpc->div.width = 3; + rpc->div.table = cpg_rpc_div_table; + rpc->div.lock = &cpg_lock; + + rpc->gate.reg = rpcckcr; + rpc->gate.bit_idx = 8; + rpc->gate.flags = CLK_GATE_SET_TO_DISABLE; + rpc->gate.lock = &cpg_lock; + + rpc->csn.reg = rpcckcr; + + clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL, + &rpc->div.hw, &clk_divider_ops, + &rpc->gate.hw, &clk_gate_ops, + CLK_SET_RATE_PARENT); + if (IS_ERR(clk)) { + kfree(rpc); + return clk; + } + + cpg_simple_notifier_register(notifiers, &rpc->csn); + return clk; +} + +struct rpcd2_clock { + struct clk_fixed_factor fixed; + struct clk_gate gate; +}; + +struct clk * __init cpg_rpcd2_clk_register(const char *name, + void __iomem *rpcckcr, + const char *parent_name) +{ + struct rpcd2_clock *rpcd2; + struct clk *clk; + + rpcd2 = kzalloc(sizeof(*rpcd2), GFP_KERNEL); + if (!rpcd2) + return ERR_PTR(-ENOMEM); + + rpcd2->fixed.mult = 1; + rpcd2->fixed.div = 2; + + rpcd2->gate.reg = rpcckcr; + rpcd2->gate.bit_idx = 9; + rpcd2->gate.flags = CLK_GATE_SET_TO_DISABLE; + rpcd2->gate.lock = &cpg_lock; + + clk = clk_register_composite(NULL, name, &parent_name, 1, NULL, NULL, + &rpcd2->fixed.hw, &clk_fixed_factor_ops, + &rpcd2->gate.hw, &clk_gate_ops, + CLK_SET_RATE_PARENT); + if (IS_ERR(clk)) + kfree(rpcd2); + + return clk; +} + |