WIP FPC-III support

[linux/fpc-iii.git] / arch / mips / alchemy / common / clock.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Alchemy clocks.
 *
 * Exposes all configurable internal clock sources to the clk framework.
 *
 * We have:
 *  - Root source, usually 12MHz supplied by an external crystal
 *  - 3 PLLs which generate multiples of root rate [AUX, CPU, AUX2]
 *
 * Dividers:
 *  - 6 clock dividers with:
 *   * selectable source [one of the PLLs],
 *   * output divided between [2 .. 512 in steps of 2] (!Au1300)
 *     or [1 .. 256 in steps of 1] (Au1300),
 *   * can be enabled individually.
 *
 * - up to 6 "internal" (fixed) consumers which:
 *   * take either AUXPLL or one of the above 6 dividers as input,
 *   * divide this input by 1, 2, or 4 (and 3 on Au1300).
 *   * can be disabled separately.
 *
 * Misc clocks:
 * - sysbus clock: CPU core clock (CPUPLL) divided by 2, 3 or 4.
 *    depends on board design and should be set by bootloader, read-only.
 * - peripheral clock: half the rate of sysbus clock, source for a lot
 *    of peripheral blocks, read-only.
 * - memory clock: clk rate to main memory chips, depends on board
 *    design and is read-only,
 * - lrclk: the static bus clock signal for synchronous operation.
 *    depends on board design, must be set by bootloader,
 *    but may be required to correctly configure devices attached to
 *    the static bus. The Au1000/1500/1100 manuals call it LCLK, on
 *    later models it's called RCLK.
 */

#include <linux/init.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <asm/mach-au1x00/au1000.h>

/* Base clock: 12MHz is the default in all databooks, and I haven't
 * found any board yet which uses a different rate.
 */
#define ALCHEMY_ROOTCLK_RATE    12000000

/*
 * the internal sources which can be driven by the PLLs and dividers.
 * Names taken from the databooks, refer to them for more information,
 * especially which ones are share a clock line.
 */
static const char * const alchemy_au1300_intclknames[] = {
        "lcd_intclk", "gpemgp_clk", "maempe_clk", "maebsa_clk",
        "EXTCLK0", "EXTCLK1"
};

static const char * const alchemy_au1200_intclknames[] = {
        "lcd_intclk", NULL, NULL, NULL, "EXTCLK0", "EXTCLK1"
};

static const char * const alchemy_au1550_intclknames[] = {
        "usb_clk", "psc0_intclk", "psc1_intclk", "pci_clko",
        "EXTCLK0", "EXTCLK1"
};

static const char * const alchemy_au1100_intclknames[] = {
        "usb_clk", "lcd_intclk", NULL, "i2s_clk", "EXTCLK0", "EXTCLK1"
};

static const char * const alchemy_au1500_intclknames[] = {
        NULL, "usbd_clk", "usbh_clk", "pci_clko", "EXTCLK0", "EXTCLK1"
};

static const char * const alchemy_au1000_intclknames[] = {
        "irda_clk", "usbd_clk", "usbh_clk", "i2s_clk", "EXTCLK0",
        "EXTCLK1"
};

/* aliases for a few on-chip sources which are either shared
 * or have gone through name changes.
 */
static struct clk_aliastable {
        char *alias;
        char *base;
        int cputype;
} alchemy_clk_aliases[] __initdata = {
        { "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
        { "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
        { "irda_clk", "usb_clk",    ALCHEMY_CPU_AU1100 },
        { "usbh_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
        { "usbd_clk", "usb_clk",    ALCHEMY_CPU_AU1550 },
        { "psc2_intclk", "usb_clk", ALCHEMY_CPU_AU1550 },
        { "psc3_intclk", "EXTCLK0", ALCHEMY_CPU_AU1550 },
        { "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1200 },
        { "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1200 },
        { "psc0_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
        { "psc2_intclk", "EXTCLK0", ALCHEMY_CPU_AU1300 },
        { "psc1_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },
        { "psc3_intclk", "EXTCLK1", ALCHEMY_CPU_AU1300 },

        { NULL, NULL, 0 },
};

#define IOMEM(x)        ((void __iomem *)(KSEG1ADDR(CPHYSADDR(x))))

/* access locks to SYS_FREQCTRL0/1 and SYS_CLKSRC registers */
static spinlock_t alchemy_clk_fg0_lock;
static spinlock_t alchemy_clk_fg1_lock;
static spinlock_t alchemy_clk_csrc_lock;

/* CPU Core clock *****************************************************/

static unsigned long alchemy_clk_cpu_recalc(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        unsigned long t;

        /*
         * On early Au1000, sys_cpupll was write-only. Since these
         * silicon versions of Au1000 are not sold, we don't bend
         * over backwards trying to determine the frequency.
         */
        if (unlikely(au1xxx_cpu_has_pll_wo()))
                t = 396000000;
        else {
                t = alchemy_rdsys(AU1000_SYS_CPUPLL) & 0x7f;
                if (alchemy_get_cputype() < ALCHEMY_CPU_AU1300)
                        t &= 0x3f;
                t *= parent_rate;
        }

        return t;
}

void __init alchemy_set_lpj(void)
{
        preset_lpj = alchemy_clk_cpu_recalc(NULL, ALCHEMY_ROOTCLK_RATE);
        preset_lpj /= 2 * HZ;
}

static const struct clk_ops alchemy_clkops_cpu = {
        .recalc_rate    = alchemy_clk_cpu_recalc,
};

static struct clk __init *alchemy_clk_setup_cpu(const char *parent_name,
                                                int ctype)
{
        struct clk_init_data id;
        struct clk_hw *h;
        struct clk *clk;

        h = kzalloc(sizeof(*h), GFP_KERNEL);
        if (!h)
                return ERR_PTR(-ENOMEM);

        id.name = ALCHEMY_CPU_CLK;
        id.parent_names = &parent_name;
        id.num_parents = 1;
        id.flags = 0;
        id.ops = &alchemy_clkops_cpu;
        h->init = &id;

        clk = clk_register(NULL, h);
        if (IS_ERR(clk)) {
                pr_err("failed to register clock\n");
                kfree(h);
        }

        return clk;
}

/* AUXPLLs ************************************************************/

struct alchemy_auxpll_clk {
        struct clk_hw hw;
        unsigned long reg;      /* au1300 has also AUXPLL2 */
        int maxmult;            /* max multiplier */
};
#define to_auxpll_clk(x) container_of(x, struct alchemy_auxpll_clk, hw)

static unsigned long alchemy_clk_aux_recalc(struct clk_hw *hw,
                                            unsigned long parent_rate)
{
        struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);

        return (alchemy_rdsys(a->reg) & 0xff) * parent_rate;
}

static int alchemy_clk_aux_setr(struct clk_hw *hw,
                                unsigned long rate,
                                unsigned long parent_rate)
{
        struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
        unsigned long d = rate;

        if (rate)
                d /= parent_rate;
        else
                d = 0;

        /* minimum is 84MHz, max is 756-1032 depending on variant */
        if (((d < 7) && (d != 0)) || (d > a->maxmult))
                return -EINVAL;

        alchemy_wrsys(d, a->reg);
        return 0;
}

static long alchemy_clk_aux_roundr(struct clk_hw *hw,
                                            unsigned long rate,
                                            unsigned long *parent_rate)
{
        struct alchemy_auxpll_clk *a = to_auxpll_clk(hw);
        unsigned long mult;

        if (!rate || !*parent_rate)
                return 0;

        mult = rate / (*parent_rate);

        if (mult && (mult < 7))
                mult = 7;
        if (mult > a->maxmult)
                mult = a->maxmult;

        return (*parent_rate) * mult;
}

static const struct clk_ops alchemy_clkops_aux = {
        .recalc_rate    = alchemy_clk_aux_recalc,
        .set_rate       = alchemy_clk_aux_setr,
        .round_rate     = alchemy_clk_aux_roundr,
};

static struct clk __init *alchemy_clk_setup_aux(const char *parent_name,
                                                char *name, int maxmult,
                                                unsigned long reg)
{
        struct clk_init_data id;
        struct clk *c;
        struct alchemy_auxpll_clk *a;

        a = kzalloc(sizeof(*a), GFP_KERNEL);
        if (!a)
                return ERR_PTR(-ENOMEM);

        id.name = name;
        id.parent_names = &parent_name;
        id.num_parents = 1;
        id.flags = CLK_GET_RATE_NOCACHE;
        id.ops = &alchemy_clkops_aux;

        a->reg = reg;
        a->maxmult = maxmult;
        a->hw.init = &id;

        c = clk_register(NULL, &a->hw);
        if (!IS_ERR(c))
                clk_register_clkdev(c, name, NULL);
        else
                kfree(a);

        return c;
}

/* sysbus_clk *********************************************************/

static struct clk __init  *alchemy_clk_setup_sysbus(const char *pn)
{
        unsigned long v = (alchemy_rdsys(AU1000_SYS_POWERCTRL) & 3) + 2;
        struct clk *c;

        c = clk_register_fixed_factor(NULL, ALCHEMY_SYSBUS_CLK,
                                      pn, 0, 1, v);
        if (!IS_ERR(c))
                clk_register_clkdev(c, ALCHEMY_SYSBUS_CLK, NULL);
        return c;
}

/* Peripheral Clock ***************************************************/

static struct clk __init *alchemy_clk_setup_periph(const char *pn)
{
        /* Peripheral clock runs at half the rate of sysbus clk */
        struct clk *c;

        c = clk_register_fixed_factor(NULL, ALCHEMY_PERIPH_CLK,
                                      pn, 0, 1, 2);
        if (!IS_ERR(c))
                clk_register_clkdev(c, ALCHEMY_PERIPH_CLK, NULL);
        return c;
}

/* mem clock **********************************************************/

static struct clk __init *alchemy_clk_setup_mem(const char *pn, int ct)
{
        void __iomem *addr = IOMEM(AU1000_MEM_PHYS_ADDR);
        unsigned long v;
        struct clk *c;
        int div;

        switch (ct) {
        case ALCHEMY_CPU_AU1550:
        case ALCHEMY_CPU_AU1200:
                v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
                div = (v & (1 << 15)) ? 1 : 2;
                break;
        case ALCHEMY_CPU_AU1300:
                v = __raw_readl(addr + AU1550_MEM_SDCONFIGB);
                div = (v & (1 << 31)) ? 1 : 2;
                break;
        case ALCHEMY_CPU_AU1000:
        case ALCHEMY_CPU_AU1500:
        case ALCHEMY_CPU_AU1100:
        default:
                div = 2;
                break;
        }

        c = clk_register_fixed_factor(NULL, ALCHEMY_MEM_CLK, pn,
                                      0, 1, div);
        if (!IS_ERR(c))
                clk_register_clkdev(c, ALCHEMY_MEM_CLK, NULL);
        return c;
}

/* lrclk: external synchronous static bus clock ***********************/

static struct clk __init *alchemy_clk_setup_lrclk(const char *pn, int t)
{
        /* Au1000, Au1500: MEM_STCFG0[11]: If bit is set, lrclk=pclk/5,
         * otherwise lrclk=pclk/4.
         * All other variants: MEM_STCFG0[15:13] = divisor.
         * L/RCLK = periph_clk / (divisor + 1)
         * On Au1000, Au1500, Au1100 it's called LCLK,
         * on later models it's called RCLK, but it's the same thing.
         */
        struct clk *c;
        unsigned long v = alchemy_rdsmem(AU1000_MEM_STCFG0);

        switch (t) {
        case ALCHEMY_CPU_AU1000:
        case ALCHEMY_CPU_AU1500:
                v = 4 + ((v >> 11) & 1);
                break;
        default:        /* all other models */
                v = ((v >> 13) & 7) + 1;
        }
        c = clk_register_fixed_factor(NULL, ALCHEMY_LR_CLK,
                                      pn, 0, 1, v);
        if (!IS_ERR(c))
                clk_register_clkdev(c, ALCHEMY_LR_CLK, NULL);
        return c;
}

/* Clock dividers and muxes *******************************************/

/* data for fgen and csrc mux-dividers */
struct alchemy_fgcs_clk {
        struct clk_hw hw;
        spinlock_t *reglock;    /* register lock                  */
        unsigned long reg;      /* SYS_FREQCTRL0/1                */
        int shift;              /* offset in register             */
        int parent;             /* parent before disable [Au1300] */
        int isen;               /* is it enabled?                 */
        int *dt;                /* dividertable for csrc          */
};
#define to_fgcs_clk(x) container_of(x, struct alchemy_fgcs_clk, hw)

static long alchemy_calc_div(unsigned long rate, unsigned long prate,
                               int scale, int maxdiv, unsigned long *rv)
{
        long div1, div2;

        div1 = prate / rate;
        if ((prate / div1) > rate)
                div1++;

        if (scale == 2) {       /* only div-by-multiple-of-2 possible */
                if (div1 & 1)
                        div1++; /* stay <=prate */
        }

        div2 = (div1 / scale) - 1;      /* value to write to register */

        if (div2 > maxdiv)
                div2 = maxdiv;
        if (rv)
                *rv = div2;

        div1 = ((div2 + 1) * scale);
        return div1;
}

static int alchemy_clk_fgcs_detr(struct clk_hw *hw,
                                 struct clk_rate_request *req,
                                 int scale, int maxdiv)
{
        struct clk_hw *pc, *bpc, *free;
        long tdv, tpr, pr, nr, br, bpr, diff, lastdiff;
        int j;

        lastdiff = INT_MAX;
        bpr = 0;
        bpc = NULL;
        br = -EINVAL;
        free = NULL;

        /* look at the rates each enabled parent supplies and select
         * the one that gets closest to but not over the requested rate.
         */
        for (j = 0; j < 7; j++) {
                pc = clk_hw_get_parent_by_index(hw, j);
                if (!pc)
                        break;

                /* if this parent is currently unused, remember it.
                 * XXX: we would actually want clk_has_active_children()
                 * but this is a good-enough approximation for now.
                 */
                if (!clk_hw_is_prepared(pc)) {
                        if (!free)
                                free = pc;
                }

                pr = clk_hw_get_rate(pc);
                if (pr < req->rate)
                        continue;

                /* what can hardware actually provide */
                tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv, NULL);
                nr = pr / tdv;
                diff = req->rate - nr;
                if (nr > req->rate)
                        continue;

                if (diff < lastdiff) {
                        lastdiff = diff;
                        bpr = pr;
                        bpc = pc;
                        br = nr;
                }
                if (diff == 0)
                        break;
        }

        /* if we couldn't get the exact rate we wanted from the enabled
         * parents, maybe we can tell an available disabled/inactive one
         * to give us a rate we can divide down to the requested rate.
         */
        if (lastdiff && free) {
                for (j = (maxdiv == 4) ? 1 : scale; j <= maxdiv; j += scale) {
                        tpr = req->rate * j;
                        if (tpr < 0)
                                break;
                        pr = clk_hw_round_rate(free, tpr);

                        tdv = alchemy_calc_div(req->rate, pr, scale, maxdiv,
                                               NULL);
                        nr = pr / tdv;
                        diff = req->rate - nr;
                        if (nr > req->rate)
                                continue;
                        if (diff < lastdiff) {
                                lastdiff = diff;
                                bpr = pr;
                                bpc = free;
                                br = nr;
                        }
                        if (diff == 0)
                                break;
                }
        }

        if (br < 0)
                return br;

        req->best_parent_rate = bpr;
        req->best_parent_hw = bpc;
        req->rate = br;

        return 0;
}

static int alchemy_clk_fgv1_en(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v, flags;

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v |= (1 << 1) << c->shift;
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static int alchemy_clk_fgv1_isen(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 1);

        return v & 1;
}

static void alchemy_clk_fgv1_dis(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v, flags;

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~((1 << 1) << c->shift);
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);
}

static int alchemy_clk_fgv1_setp(struct clk_hw *hw, u8 index)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v, flags;

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        if (index)
                v |= (1 << c->shift);
        else
                v &= ~(1 << c->shift);
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static u8 alchemy_clk_fgv1_getp(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);

        return (alchemy_rdsys(c->reg) >> c->shift) & 1;
}

static int alchemy_clk_fgv1_setr(struct clk_hw *hw, unsigned long rate,
                                 unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long div, v, flags, ret;
        int sh = c->shift + 2;

        if (!rate || !parent_rate || rate > (parent_rate / 2))
                return -EINVAL;
        ret = alchemy_calc_div(rate, parent_rate, 2, 512, &div);
        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~(0xff << sh);
        v |= div << sh;
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static unsigned long alchemy_clk_fgv1_recalc(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v = alchemy_rdsys(c->reg) >> (c->shift + 2);

        v = ((v & 0xff) + 1) * 2;
        return parent_rate / v;
}

static int alchemy_clk_fgv1_detr(struct clk_hw *hw,
                                 struct clk_rate_request *req)
{
        return alchemy_clk_fgcs_detr(hw, req, 2, 512);
}

/* Au1000, Au1100, Au15x0, Au12x0 */
static const struct clk_ops alchemy_clkops_fgenv1 = {
        .recalc_rate    = alchemy_clk_fgv1_recalc,
        .determine_rate = alchemy_clk_fgv1_detr,
        .set_rate       = alchemy_clk_fgv1_setr,
        .set_parent     = alchemy_clk_fgv1_setp,
        .get_parent     = alchemy_clk_fgv1_getp,
        .enable         = alchemy_clk_fgv1_en,
        .disable        = alchemy_clk_fgv1_dis,
        .is_enabled     = alchemy_clk_fgv1_isen,
};

static void __alchemy_clk_fgv2_en(struct alchemy_fgcs_clk *c)
{
        unsigned long v = alchemy_rdsys(c->reg);

        v &= ~(3 << c->shift);
        v |= (c->parent & 3) << c->shift;
        alchemy_wrsys(v, c->reg);
        c->isen = 1;
}

static int alchemy_clk_fgv2_en(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long flags;

        /* enable by setting the previous parent clock */
        spin_lock_irqsave(c->reglock, flags);
        __alchemy_clk_fgv2_en(c);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static int alchemy_clk_fgv2_isen(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);

        return ((alchemy_rdsys(c->reg) >> c->shift) & 3) != 0;
}

static void alchemy_clk_fgv2_dis(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v, flags;

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~(3 << c->shift);  /* set input mux to "disabled" state */
        alchemy_wrsys(v, c->reg);
        c->isen = 0;
        spin_unlock_irqrestore(c->reglock, flags);
}

static int alchemy_clk_fgv2_setp(struct clk_hw *hw, u8 index)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long flags;

        spin_lock_irqsave(c->reglock, flags);
        c->parent = index + 1;  /* value to write to register */
        if (c->isen)
                __alchemy_clk_fgv2_en(c);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static u8 alchemy_clk_fgv2_getp(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long flags, v;

        spin_lock_irqsave(c->reglock, flags);
        v = c->parent - 1;
        spin_unlock_irqrestore(c->reglock, flags);
        return v;
}

/* fg0-2 and fg4-6 share a "scale"-bit. With this bit cleared, the
 * dividers behave exactly as on previous models (dividers are multiples
 * of 2); with the bit set, dividers are multiples of 1, halving their
 * range, but making them also much more flexible.
 */
static int alchemy_clk_fgv2_setr(struct clk_hw *hw, unsigned long rate,
                                 unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        int sh = c->shift + 2;
        unsigned long div, v, flags, ret;

        if (!rate || !parent_rate || rate > parent_rate)
                return -EINVAL;

        v = alchemy_rdsys(c->reg) & (1 << 30); /* test "scale" bit */
        ret = alchemy_calc_div(rate, parent_rate, v ? 1 : 2,
                               v ? 256 : 512, &div);

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~(0xff << sh);
        v |= (div & 0xff) << sh;
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static unsigned long alchemy_clk_fgv2_recalc(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        int sh = c->shift + 2;
        unsigned long v, t;

        v = alchemy_rdsys(c->reg);
        t = parent_rate / (((v >> sh) & 0xff) + 1);
        if ((v & (1 << 30)) == 0)               /* test scale bit */
                t /= 2;

        return t;
}

static int alchemy_clk_fgv2_detr(struct clk_hw *hw,
                                 struct clk_rate_request *req)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        int scale, maxdiv;

        if (alchemy_rdsys(c->reg) & (1 << 30)) {
                scale = 1;
                maxdiv = 256;
        } else {
                scale = 2;
                maxdiv = 512;
        }

        return alchemy_clk_fgcs_detr(hw, req, scale, maxdiv);
}

/* Au1300 larger input mux, no separate disable bit, flexible divider */
static const struct clk_ops alchemy_clkops_fgenv2 = {
        .recalc_rate    = alchemy_clk_fgv2_recalc,
        .determine_rate = alchemy_clk_fgv2_detr,
        .set_rate       = alchemy_clk_fgv2_setr,
        .set_parent     = alchemy_clk_fgv2_setp,
        .get_parent     = alchemy_clk_fgv2_getp,
        .enable         = alchemy_clk_fgv2_en,
        .disable        = alchemy_clk_fgv2_dis,
        .is_enabled     = alchemy_clk_fgv2_isen,
};

static const char * const alchemy_clk_fgv1_parents[] = {
        ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
};

static const char * const alchemy_clk_fgv2_parents[] = {
        ALCHEMY_AUXPLL2_CLK, ALCHEMY_CPU_CLK, ALCHEMY_AUXPLL_CLK
};

static const char * const alchemy_clk_fgen_names[] = {
        ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
        ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK };

static int __init alchemy_clk_init_fgens(int ctype)
{
        struct clk *c;
        struct clk_init_data id;
        struct alchemy_fgcs_clk *a;
        unsigned long v;
        int i, ret;

        switch (ctype) {
        case ALCHEMY_CPU_AU1000...ALCHEMY_CPU_AU1200:
                id.ops = &alchemy_clkops_fgenv1;
                id.parent_names = alchemy_clk_fgv1_parents;
                id.num_parents = 2;
                break;
        case ALCHEMY_CPU_AU1300:
                id.ops = &alchemy_clkops_fgenv2;
                id.parent_names = alchemy_clk_fgv2_parents;
                id.num_parents = 3;
                break;
        default:
                return -ENODEV;
        }
        id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;

        a = kzalloc((sizeof(*a)) * 6, GFP_KERNEL);
        if (!a)
                return -ENOMEM;

        spin_lock_init(&alchemy_clk_fg0_lock);
        spin_lock_init(&alchemy_clk_fg1_lock);
        ret = 0;
        for (i = 0; i < 6; i++) {
                id.name = alchemy_clk_fgen_names[i];
                a->shift = 10 * (i < 3 ? i : i - 3);
                if (i > 2) {
                        a->reg = AU1000_SYS_FREQCTRL1;
                        a->reglock = &alchemy_clk_fg1_lock;
                } else {
                        a->reg = AU1000_SYS_FREQCTRL0;
                        a->reglock = &alchemy_clk_fg0_lock;
                }

                /* default to first parent if bootloader has set
                 * the mux to disabled state.
                 */
                if (ctype == ALCHEMY_CPU_AU1300) {
                        v = alchemy_rdsys(a->reg);
                        a->parent = (v >> a->shift) & 3;
                        if (!a->parent) {
                                a->parent = 1;
                                a->isen = 0;
                        } else
                                a->isen = 1;
                }

                a->hw.init = &id;
                c = clk_register(NULL, &a->hw);
                if (IS_ERR(c))
                        ret++;
                else
                        clk_register_clkdev(c, id.name, NULL);
                a++;
        }

        return ret;
}

/* internal sources muxes *********************************************/

static int alchemy_clk_csrc_isen(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v = alchemy_rdsys(c->reg);

        return (((v >> c->shift) >> 2) & 7) != 0;
}

static void __alchemy_clk_csrc_en(struct alchemy_fgcs_clk *c)
{
        unsigned long v = alchemy_rdsys(c->reg);

        v &= ~((7 << 2) << c->shift);
        v |= ((c->parent & 7) << 2) << c->shift;
        alchemy_wrsys(v, c->reg);
        c->isen = 1;
}

static int alchemy_clk_csrc_en(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long flags;

        /* enable by setting the previous parent clock */
        spin_lock_irqsave(c->reglock, flags);
        __alchemy_clk_csrc_en(c);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static void alchemy_clk_csrc_dis(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v, flags;

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~((3 << 2) << c->shift);   /* mux to "disabled" state */
        alchemy_wrsys(v, c->reg);
        c->isen = 0;
        spin_unlock_irqrestore(c->reglock, flags);
}

static int alchemy_clk_csrc_setp(struct clk_hw *hw, u8 index)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long flags;

        spin_lock_irqsave(c->reglock, flags);
        c->parent = index + 1;  /* value to write to register */
        if (c->isen)
                __alchemy_clk_csrc_en(c);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static u8 alchemy_clk_csrc_getp(struct clk_hw *hw)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);

        return c->parent - 1;
}

static unsigned long alchemy_clk_csrc_recalc(struct clk_hw *hw,
                                             unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long v = (alchemy_rdsys(c->reg) >> c->shift) & 3;

        return parent_rate / c->dt[v];
}

static int alchemy_clk_csrc_setr(struct clk_hw *hw, unsigned long rate,
                                 unsigned long parent_rate)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        unsigned long d, v, flags;
        int i;

        if (!rate || !parent_rate || rate > parent_rate)
                return -EINVAL;

        d = (parent_rate + (rate / 2)) / rate;
        if (d > 4)
                return -EINVAL;
        if ((d == 3) && (c->dt[2] != 3))
                d = 4;

        for (i = 0; i < 4; i++)
                if (c->dt[i] == d)
                        break;

        if (i >= 4)
                return -EINVAL; /* oops */

        spin_lock_irqsave(c->reglock, flags);
        v = alchemy_rdsys(c->reg);
        v &= ~(3 << c->shift);
        v |= (i & 3) << c->shift;
        alchemy_wrsys(v, c->reg);
        spin_unlock_irqrestore(c->reglock, flags);

        return 0;
}

static int alchemy_clk_csrc_detr(struct clk_hw *hw,
                                 struct clk_rate_request *req)
{
        struct alchemy_fgcs_clk *c = to_fgcs_clk(hw);
        int scale = c->dt[2] == 3 ? 1 : 2; /* au1300 check */

        return alchemy_clk_fgcs_detr(hw, req, scale, 4);
}

static const struct clk_ops alchemy_clkops_csrc = {
        .recalc_rate    = alchemy_clk_csrc_recalc,
        .determine_rate = alchemy_clk_csrc_detr,
        .set_rate       = alchemy_clk_csrc_setr,
        .set_parent     = alchemy_clk_csrc_setp,
        .get_parent     = alchemy_clk_csrc_getp,
        .enable         = alchemy_clk_csrc_en,
        .disable        = alchemy_clk_csrc_dis,
        .is_enabled     = alchemy_clk_csrc_isen,
};

static const char * const alchemy_clk_csrc_parents[] = {
        /* disabled at index 0 */ ALCHEMY_AUXPLL_CLK,
        ALCHEMY_FG0_CLK, ALCHEMY_FG1_CLK, ALCHEMY_FG2_CLK,
        ALCHEMY_FG3_CLK, ALCHEMY_FG4_CLK, ALCHEMY_FG5_CLK
};

/* divider tables */
static int alchemy_csrc_dt1[] = { 1, 4, 1, 2 }; /* rest */
static int alchemy_csrc_dt2[] = { 1, 4, 3, 2 }; /* Au1300 */

static int __init alchemy_clk_setup_imux(int ctype)
{
        struct alchemy_fgcs_clk *a;
        const char * const *names;
        struct clk_init_data id;
        unsigned long v;
        int i, ret, *dt;
        struct clk *c;

        id.ops = &alchemy_clkops_csrc;
        id.parent_names = alchemy_clk_csrc_parents;
        id.num_parents = 7;
        id.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE;

        dt = alchemy_csrc_dt1;
        switch (ctype) {
        case ALCHEMY_CPU_AU1000:
                names = alchemy_au1000_intclknames;
                break;
        case ALCHEMY_CPU_AU1500:
                names = alchemy_au1500_intclknames;
                break;
        case ALCHEMY_CPU_AU1100:
                names = alchemy_au1100_intclknames;
                break;
        case ALCHEMY_CPU_AU1550:
                names = alchemy_au1550_intclknames;
                break;
        case ALCHEMY_CPU_AU1200:
                names = alchemy_au1200_intclknames;
                break;
        case ALCHEMY_CPU_AU1300:
                dt = alchemy_csrc_dt2;
                names = alchemy_au1300_intclknames;
                break;
        default:
                return -ENODEV;
        }

        a = kcalloc(6, sizeof(*a), GFP_KERNEL);
        if (!a)
                return -ENOMEM;

        spin_lock_init(&alchemy_clk_csrc_lock);
        ret = 0;

        for (i = 0; i < 6; i++) {
                id.name = names[i];
                if (!id.name)
                        goto next;

                a->shift = i * 5;
                a->reg = AU1000_SYS_CLKSRC;
                a->reglock = &alchemy_clk_csrc_lock;
                a->dt = dt;

                /* default to first parent clock if mux is initially
                 * set to disabled state.
                 */
                v = alchemy_rdsys(a->reg);
                a->parent = ((v >> a->shift) >> 2) & 7;
                if (!a->parent) {
                        a->parent = 1;
                        a->isen = 0;
                } else
                        a->isen = 1;

                a->hw.init = &id;
                c = clk_register(NULL, &a->hw);
                if (IS_ERR(c))
                        ret++;
                else
                        clk_register_clkdev(c, id.name, NULL);
next:
                a++;
        }

        return ret;
}


/**********************************************************************/


#define ERRCK(x)                                                \
        if (IS_ERR(x)) {                                        \
                ret = PTR_ERR(x);                               \
                goto out;                                       \
        }

static int __init alchemy_clk_init(void)
{
        int ctype = alchemy_get_cputype(), ret, i;
        struct clk_aliastable *t = alchemy_clk_aliases;
        struct clk *c;

        /* Root of the Alchemy clock tree: external 12MHz crystal osc */
        c = clk_register_fixed_rate(NULL, ALCHEMY_ROOT_CLK, NULL,
                                           0, ALCHEMY_ROOTCLK_RATE);
        ERRCK(c)

        /* CPU core clock */
        c = alchemy_clk_setup_cpu(ALCHEMY_ROOT_CLK, ctype);
        ERRCK(c)

        /* AUXPLLs: max 1GHz on Au1300, 748MHz on older models */
        i = (ctype == ALCHEMY_CPU_AU1300) ? 84 : 63;
        c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK, ALCHEMY_AUXPLL_CLK,
                                  i, AU1000_SYS_AUXPLL);
        ERRCK(c)

        if (ctype == ALCHEMY_CPU_AU1300) {
                c = alchemy_clk_setup_aux(ALCHEMY_ROOT_CLK,
                                          ALCHEMY_AUXPLL2_CLK, i,
                                          AU1300_SYS_AUXPLL2);
                ERRCK(c)
        }

        /* sysbus clock: cpu core clock divided by 2, 3 or 4 */
        c = alchemy_clk_setup_sysbus(ALCHEMY_CPU_CLK);
        ERRCK(c)

        /* peripheral clock: runs at half rate of sysbus clk */
        c = alchemy_clk_setup_periph(ALCHEMY_SYSBUS_CLK);
        ERRCK(c)

        /* SDR/DDR memory clock */
        c = alchemy_clk_setup_mem(ALCHEMY_SYSBUS_CLK, ctype);
        ERRCK(c)

        /* L/RCLK: external static bus clock for synchronous mode */
        c = alchemy_clk_setup_lrclk(ALCHEMY_PERIPH_CLK, ctype);
        ERRCK(c)

        /* Frequency dividers 0-5 */
        ret = alchemy_clk_init_fgens(ctype);
        if (ret) {
                ret = -ENODEV;
                goto out;
        }

        /* diving muxes for internal sources */
        ret = alchemy_clk_setup_imux(ctype);
        if (ret) {
                ret = -ENODEV;
                goto out;
        }

        /* set up aliases drivers might look for */
        while (t->base) {
                if (t->cputype == ctype)
                        clk_add_alias(t->alias, NULL, t->base, NULL);
                t++;
        }

        pr_info("Alchemy clocktree installed\n");
        return 0;

out:
        return ret;
}
postcore_initcall(alchemy_clk_init);