| /* |
| * clk-xgene.c - AppliedMicro X-Gene Clock Interface |
| * |
| * Copyright (c) 2013, Applied Micro Circuits Corporation |
| * Author: Loc Ho <lho@apm.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of |
| * the License, or (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| * MA 02111-1307 USA |
| * |
| */ |
| #include <linux/module.h> |
| #include <linux/spinlock.h> |
| #include <linux/io.h> |
| #include <linux/of.h> |
| #include <linux/clkdev.h> |
| #include <linux/clk-provider.h> |
| #include <linux/of_address.h> |
| |
| /* Register SCU_PCPPLL bit fields */ |
| #define N_DIV_RD(src) ((src) & 0x000001ff) |
| #define SC_N_DIV_RD(src) ((src) & 0x0000007f) |
| #define SC_OUTDIV2(src) (((src) & 0x00000100) >> 8) |
| |
| /* Register SCU_SOCPLL bit fields */ |
| #define CLKR_RD(src) (((src) & 0x07000000)>>24) |
| #define CLKOD_RD(src) (((src) & 0x00300000)>>20) |
| #define REGSPEC_RESET_F1_MASK 0x00010000 |
| #define CLKF_RD(src) (((src) & 0x000001ff)) |
| |
| #define XGENE_CLK_DRIVER_VER "0.1" |
| |
| static DEFINE_SPINLOCK(clk_lock); |
| |
| static inline u32 xgene_clk_read(void __iomem *csr) |
| { |
| return readl_relaxed(csr); |
| } |
| |
| static inline void xgene_clk_write(u32 data, void __iomem *csr) |
| { |
| writel_relaxed(data, csr); |
| } |
| |
| /* PLL Clock */ |
| enum xgene_pll_type { |
| PLL_TYPE_PCP = 0, |
| PLL_TYPE_SOC = 1, |
| }; |
| |
| struct xgene_clk_pll { |
| struct clk_hw hw; |
| void __iomem *reg; |
| spinlock_t *lock; |
| u32 pll_offset; |
| enum xgene_pll_type type; |
| int version; |
| }; |
| |
| #define to_xgene_clk_pll(_hw) container_of(_hw, struct xgene_clk_pll, hw) |
| |
| static int xgene_clk_pll_is_enabled(struct clk_hw *hw) |
| { |
| struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw); |
| u32 data; |
| |
| data = xgene_clk_read(pllclk->reg + pllclk->pll_offset); |
| pr_debug("%s pll %s\n", clk_hw_get_name(hw), |
| data & REGSPEC_RESET_F1_MASK ? "disabled" : "enabled"); |
| |
| return data & REGSPEC_RESET_F1_MASK ? 0 : 1; |
| } |
| |
| static unsigned long xgene_clk_pll_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw); |
| unsigned long fref; |
| unsigned long fvco; |
| u32 pll; |
| u32 nref; |
| u32 nout; |
| u32 nfb; |
| |
| pll = xgene_clk_read(pllclk->reg + pllclk->pll_offset); |
| |
| if (pllclk->version <= 1) { |
| if (pllclk->type == PLL_TYPE_PCP) { |
| /* |
| * PLL VCO = Reference clock * NF |
| * PCP PLL = PLL_VCO / 2 |
| */ |
| nout = 2; |
| fvco = parent_rate * (N_DIV_RD(pll) + 4); |
| } else { |
| /* |
| * Fref = Reference Clock / NREF; |
| * Fvco = Fref * NFB; |
| * Fout = Fvco / NOUT; |
| */ |
| nref = CLKR_RD(pll) + 1; |
| nout = CLKOD_RD(pll) + 1; |
| nfb = CLKF_RD(pll); |
| fref = parent_rate / nref; |
| fvco = fref * nfb; |
| } |
| } else { |
| /* |
| * fvco = Reference clock * FBDIVC |
| * PLL freq = fvco / NOUT |
| */ |
| nout = SC_OUTDIV2(pll) ? 2 : 3; |
| fvco = parent_rate * SC_N_DIV_RD(pll); |
| } |
| pr_debug("%s pll recalc rate %ld parent %ld version %d\n", |
| clk_hw_get_name(hw), fvco / nout, parent_rate, |
| pllclk->version); |
| |
| return fvco / nout; |
| } |
| |
| static const struct clk_ops xgene_clk_pll_ops = { |
| .is_enabled = xgene_clk_pll_is_enabled, |
| .recalc_rate = xgene_clk_pll_recalc_rate, |
| }; |
| |
| static struct clk *xgene_register_clk_pll(struct device *dev, |
| const char *name, const char *parent_name, |
| unsigned long flags, void __iomem *reg, u32 pll_offset, |
| u32 type, spinlock_t *lock, int version) |
| { |
| struct xgene_clk_pll *apmclk; |
| struct clk *clk; |
| struct clk_init_data init; |
| |
| /* allocate the APM clock structure */ |
| apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL); |
| if (!apmclk) { |
| pr_err("%s: could not allocate APM clk\n", __func__); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| init.name = name; |
| init.ops = &xgene_clk_pll_ops; |
| init.flags = flags; |
| init.parent_names = parent_name ? &parent_name : NULL; |
| init.num_parents = parent_name ? 1 : 0; |
| |
| apmclk->version = version; |
| apmclk->reg = reg; |
| apmclk->lock = lock; |
| apmclk->pll_offset = pll_offset; |
| apmclk->type = type; |
| apmclk->hw.init = &init; |
| |
| /* Register the clock */ |
| clk = clk_register(dev, &apmclk->hw); |
| if (IS_ERR(clk)) { |
| pr_err("%s: could not register clk %s\n", __func__, name); |
| kfree(apmclk); |
| return NULL; |
| } |
| return clk; |
| } |
| |
| static int xgene_pllclk_version(struct device_node *np) |
| { |
| if (of_device_is_compatible(np, "apm,xgene-socpll-clock")) |
| return 1; |
| if (of_device_is_compatible(np, "apm,xgene-pcppll-clock")) |
| return 1; |
| return 2; |
| } |
| |
| static void xgene_pllclk_init(struct device_node *np, enum xgene_pll_type pll_type) |
| { |
| const char *clk_name = np->full_name; |
| struct clk *clk; |
| void __iomem *reg; |
| int version = xgene_pllclk_version(np); |
| |
| reg = of_iomap(np, 0); |
| if (reg == NULL) { |
| pr_err("Unable to map CSR register for %s\n", np->full_name); |
| return; |
| } |
| of_property_read_string(np, "clock-output-names", &clk_name); |
| clk = xgene_register_clk_pll(NULL, |
| clk_name, of_clk_get_parent_name(np, 0), |
| CLK_IS_ROOT, reg, 0, pll_type, &clk_lock, |
| version); |
| if (!IS_ERR(clk)) { |
| of_clk_add_provider(np, of_clk_src_simple_get, clk); |
| clk_register_clkdev(clk, clk_name, NULL); |
| pr_debug("Add %s clock PLL\n", clk_name); |
| } |
| } |
| |
| static void xgene_socpllclk_init(struct device_node *np) |
| { |
| xgene_pllclk_init(np, PLL_TYPE_SOC); |
| } |
| |
| static void xgene_pcppllclk_init(struct device_node *np) |
| { |
| xgene_pllclk_init(np, PLL_TYPE_PCP); |
| } |
| |
| /* IP Clock */ |
| struct xgene_dev_parameters { |
| void __iomem *csr_reg; /* CSR for IP clock */ |
| u32 reg_clk_offset; /* Offset to clock enable CSR */ |
| u32 reg_clk_mask; /* Mask bit for clock enable */ |
| u32 reg_csr_offset; /* Offset to CSR reset */ |
| u32 reg_csr_mask; /* Mask bit for disable CSR reset */ |
| void __iomem *divider_reg; /* CSR for divider */ |
| u32 reg_divider_offset; /* Offset to divider register */ |
| u32 reg_divider_shift; /* Bit shift to divider field */ |
| u32 reg_divider_width; /* Width of the bit to divider field */ |
| }; |
| |
| struct xgene_clk { |
| struct clk_hw hw; |
| spinlock_t *lock; |
| struct xgene_dev_parameters param; |
| }; |
| |
| #define to_xgene_clk(_hw) container_of(_hw, struct xgene_clk, hw) |
| |
| static int xgene_clk_enable(struct clk_hw *hw) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| unsigned long flags = 0; |
| u32 data; |
| phys_addr_t reg; |
| |
| if (pclk->lock) |
| spin_lock_irqsave(pclk->lock, flags); |
| |
| if (pclk->param.csr_reg != NULL) { |
| pr_debug("%s clock enabled\n", clk_hw_get_name(hw)); |
| reg = __pa(pclk->param.csr_reg); |
| /* First enable the clock */ |
| data = xgene_clk_read(pclk->param.csr_reg + |
| pclk->param.reg_clk_offset); |
| data |= pclk->param.reg_clk_mask; |
| xgene_clk_write(data, pclk->param.csr_reg + |
| pclk->param.reg_clk_offset); |
| pr_debug("%s clock PADDR base %pa clk offset 0x%08X mask 0x%08X value 0x%08X\n", |
| clk_hw_get_name(hw), ®, |
| pclk->param.reg_clk_offset, pclk->param.reg_clk_mask, |
| data); |
| |
| /* Second enable the CSR */ |
| data = xgene_clk_read(pclk->param.csr_reg + |
| pclk->param.reg_csr_offset); |
| data &= ~pclk->param.reg_csr_mask; |
| xgene_clk_write(data, pclk->param.csr_reg + |
| pclk->param.reg_csr_offset); |
| pr_debug("%s CSR RESET PADDR base %pa csr offset 0x%08X mask 0x%08X value 0x%08X\n", |
| clk_hw_get_name(hw), ®, |
| pclk->param.reg_csr_offset, pclk->param.reg_csr_mask, |
| data); |
| } |
| |
| if (pclk->lock) |
| spin_unlock_irqrestore(pclk->lock, flags); |
| |
| return 0; |
| } |
| |
| static void xgene_clk_disable(struct clk_hw *hw) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| unsigned long flags = 0; |
| u32 data; |
| |
| if (pclk->lock) |
| spin_lock_irqsave(pclk->lock, flags); |
| |
| if (pclk->param.csr_reg != NULL) { |
| pr_debug("%s clock disabled\n", clk_hw_get_name(hw)); |
| /* First put the CSR in reset */ |
| data = xgene_clk_read(pclk->param.csr_reg + |
| pclk->param.reg_csr_offset); |
| data |= pclk->param.reg_csr_mask; |
| xgene_clk_write(data, pclk->param.csr_reg + |
| pclk->param.reg_csr_offset); |
| |
| /* Second disable the clock */ |
| data = xgene_clk_read(pclk->param.csr_reg + |
| pclk->param.reg_clk_offset); |
| data &= ~pclk->param.reg_clk_mask; |
| xgene_clk_write(data, pclk->param.csr_reg + |
| pclk->param.reg_clk_offset); |
| } |
| |
| if (pclk->lock) |
| spin_unlock_irqrestore(pclk->lock, flags); |
| } |
| |
| static int xgene_clk_is_enabled(struct clk_hw *hw) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| u32 data = 0; |
| |
| if (pclk->param.csr_reg != NULL) { |
| pr_debug("%s clock checking\n", clk_hw_get_name(hw)); |
| data = xgene_clk_read(pclk->param.csr_reg + |
| pclk->param.reg_clk_offset); |
| pr_debug("%s clock is %s\n", clk_hw_get_name(hw), |
| data & pclk->param.reg_clk_mask ? "enabled" : |
| "disabled"); |
| } |
| |
| if (pclk->param.csr_reg == NULL) |
| return 1; |
| return data & pclk->param.reg_clk_mask ? 1 : 0; |
| } |
| |
| static unsigned long xgene_clk_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| u32 data; |
| |
| if (pclk->param.divider_reg) { |
| data = xgene_clk_read(pclk->param.divider_reg + |
| pclk->param.reg_divider_offset); |
| data >>= pclk->param.reg_divider_shift; |
| data &= (1 << pclk->param.reg_divider_width) - 1; |
| |
| pr_debug("%s clock recalc rate %ld parent %ld\n", |
| clk_hw_get_name(hw), |
| parent_rate / data, parent_rate); |
| |
| return parent_rate / data; |
| } else { |
| pr_debug("%s clock recalc rate %ld parent %ld\n", |
| clk_hw_get_name(hw), parent_rate, parent_rate); |
| return parent_rate; |
| } |
| } |
| |
| static int xgene_clk_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| unsigned long flags = 0; |
| u32 data; |
| u32 divider; |
| u32 divider_save; |
| |
| if (pclk->lock) |
| spin_lock_irqsave(pclk->lock, flags); |
| |
| if (pclk->param.divider_reg) { |
| /* Let's compute the divider */ |
| if (rate > parent_rate) |
| rate = parent_rate; |
| divider_save = divider = parent_rate / rate; /* Rounded down */ |
| divider &= (1 << pclk->param.reg_divider_width) - 1; |
| divider <<= pclk->param.reg_divider_shift; |
| |
| /* Set new divider */ |
| data = xgene_clk_read(pclk->param.divider_reg + |
| pclk->param.reg_divider_offset); |
| data &= ~(((1 << pclk->param.reg_divider_width) - 1) |
| << pclk->param.reg_divider_shift); |
| data |= divider; |
| xgene_clk_write(data, pclk->param.divider_reg + |
| pclk->param.reg_divider_offset); |
| pr_debug("%s clock set rate %ld\n", clk_hw_get_name(hw), |
| parent_rate / divider_save); |
| } else { |
| divider_save = 1; |
| } |
| |
| if (pclk->lock) |
| spin_unlock_irqrestore(pclk->lock, flags); |
| |
| return parent_rate / divider_save; |
| } |
| |
| static long xgene_clk_round_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long *prate) |
| { |
| struct xgene_clk *pclk = to_xgene_clk(hw); |
| unsigned long parent_rate = *prate; |
| u32 divider; |
| |
| if (pclk->param.divider_reg) { |
| /* Let's compute the divider */ |
| if (rate > parent_rate) |
| rate = parent_rate; |
| divider = parent_rate / rate; /* Rounded down */ |
| } else { |
| divider = 1; |
| } |
| |
| return parent_rate / divider; |
| } |
| |
| static const struct clk_ops xgene_clk_ops = { |
| .enable = xgene_clk_enable, |
| .disable = xgene_clk_disable, |
| .is_enabled = xgene_clk_is_enabled, |
| .recalc_rate = xgene_clk_recalc_rate, |
| .set_rate = xgene_clk_set_rate, |
| .round_rate = xgene_clk_round_rate, |
| }; |
| |
| static struct clk *xgene_register_clk(struct device *dev, |
| const char *name, const char *parent_name, |
| struct xgene_dev_parameters *parameters, spinlock_t *lock) |
| { |
| struct xgene_clk *apmclk; |
| struct clk *clk; |
| struct clk_init_data init; |
| int rc; |
| |
| /* allocate the APM clock structure */ |
| apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL); |
| if (!apmclk) { |
| pr_err("%s: could not allocate APM clk\n", __func__); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| init.name = name; |
| init.ops = &xgene_clk_ops; |
| init.flags = 0; |
| init.parent_names = parent_name ? &parent_name : NULL; |
| init.num_parents = parent_name ? 1 : 0; |
| |
| apmclk->lock = lock; |
| apmclk->hw.init = &init; |
| apmclk->param = *parameters; |
| |
| /* Register the clock */ |
| clk = clk_register(dev, &apmclk->hw); |
| if (IS_ERR(clk)) { |
| pr_err("%s: could not register clk %s\n", __func__, name); |
| kfree(apmclk); |
| return clk; |
| } |
| |
| /* Register the clock for lookup */ |
| rc = clk_register_clkdev(clk, name, NULL); |
| if (rc != 0) { |
| pr_err("%s: could not register lookup clk %s\n", |
| __func__, name); |
| } |
| return clk; |
| } |
| |
| static void __init xgene_devclk_init(struct device_node *np) |
| { |
| const char *clk_name = np->full_name; |
| struct clk *clk; |
| struct resource res; |
| int rc; |
| struct xgene_dev_parameters parameters; |
| int i; |
| |
| /* Check if the entry is disabled */ |
| if (!of_device_is_available(np)) |
| return; |
| |
| /* Parse the DTS register for resource */ |
| parameters.csr_reg = NULL; |
| parameters.divider_reg = NULL; |
| for (i = 0; i < 2; i++) { |
| void __iomem *map_res; |
| rc = of_address_to_resource(np, i, &res); |
| if (rc != 0) { |
| if (i == 0) { |
| pr_err("no DTS register for %s\n", |
| np->full_name); |
| return; |
| } |
| break; |
| } |
| map_res = of_iomap(np, i); |
| if (map_res == NULL) { |
| pr_err("Unable to map resource %d for %s\n", |
| i, np->full_name); |
| goto err; |
| } |
| if (strcmp(res.name, "div-reg") == 0) |
| parameters.divider_reg = map_res; |
| else /* if (strcmp(res->name, "csr-reg") == 0) */ |
| parameters.csr_reg = map_res; |
| } |
| if (of_property_read_u32(np, "csr-offset", ¶meters.reg_csr_offset)) |
| parameters.reg_csr_offset = 0; |
| if (of_property_read_u32(np, "csr-mask", ¶meters.reg_csr_mask)) |
| parameters.reg_csr_mask = 0xF; |
| if (of_property_read_u32(np, "enable-offset", |
| ¶meters.reg_clk_offset)) |
| parameters.reg_clk_offset = 0x8; |
| if (of_property_read_u32(np, "enable-mask", ¶meters.reg_clk_mask)) |
| parameters.reg_clk_mask = 0xF; |
| if (of_property_read_u32(np, "divider-offset", |
| ¶meters.reg_divider_offset)) |
| parameters.reg_divider_offset = 0; |
| if (of_property_read_u32(np, "divider-width", |
| ¶meters.reg_divider_width)) |
| parameters.reg_divider_width = 0; |
| if (of_property_read_u32(np, "divider-shift", |
| ¶meters.reg_divider_shift)) |
| parameters.reg_divider_shift = 0; |
| of_property_read_string(np, "clock-output-names", &clk_name); |
| |
| clk = xgene_register_clk(NULL, clk_name, |
| of_clk_get_parent_name(np, 0), ¶meters, &clk_lock); |
| if (IS_ERR(clk)) |
| goto err; |
| pr_debug("Add %s clock\n", clk_name); |
| rc = of_clk_add_provider(np, of_clk_src_simple_get, clk); |
| if (rc != 0) |
| pr_err("%s: could register provider clk %s\n", __func__, |
| np->full_name); |
| |
| return; |
| |
| err: |
| if (parameters.csr_reg) |
| iounmap(parameters.csr_reg); |
| if (parameters.divider_reg) |
| iounmap(parameters.divider_reg); |
| } |
| |
| CLK_OF_DECLARE(xgene_socpll_clock, "apm,xgene-socpll-clock", xgene_socpllclk_init); |
| CLK_OF_DECLARE(xgene_pcppll_clock, "apm,xgene-pcppll-clock", xgene_pcppllclk_init); |
| CLK_OF_DECLARE(xgene_socpll_v2_clock, "apm,xgene-socpll-v2-clock", |
| xgene_socpllclk_init); |
| CLK_OF_DECLARE(xgene_pcppll_v2_clock, "apm,xgene-pcppll-v2-clock", |
| xgene_pcppllclk_init); |
| CLK_OF_DECLARE(xgene_dev_clock, "apm,xgene-device-clock", xgene_devclk_init); |