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-rw-r--r--drivers/clk/pxa/clk-pxa.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/clk/pxa/clk-pxa.c b/drivers/clk/pxa/clk-pxa.c
new file mode 100644
index 000000000..374098ebb
--- /dev/null
+++ b/drivers/clk/pxa/clk-pxa.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Marvell PXA family clocks
+ *
+ * Copyright (C) 2014 Robert Jarzmik
+ *
+ * Common clock code for PXA clocks ("CKEN" type clocks + DT)
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/soc/pxa/smemc.h>
+
+#include <dt-bindings/clock/pxa-clock.h>
+#include "clk-pxa.h"
+
+#define KHz 1000
+#define MHz (1000 * 1000)
+
+#define MDREFR_K0DB4 (1 << 29) /* SDCLK0 Divide by 4 Control/Status */
+#define MDREFR_K2FREE (1 << 25) /* SDRAM Free-Running Control */
+#define MDREFR_K1FREE (1 << 24) /* SDRAM Free-Running Control */
+#define MDREFR_K0FREE (1 << 23) /* SDRAM Free-Running Control */
+#define MDREFR_SLFRSH (1 << 22) /* SDRAM Self-Refresh Control/Status */
+#define MDREFR_APD (1 << 20) /* SDRAM/SSRAM Auto-Power-Down Enable */
+#define MDREFR_K2DB2 (1 << 19) /* SDCLK2 Divide by 2 Control/Status */
+#define MDREFR_K2RUN (1 << 18) /* SDCLK2 Run Control/Status */
+#define MDREFR_K1DB2 (1 << 17) /* SDCLK1 Divide by 2 Control/Status */
+#define MDREFR_K1RUN (1 << 16) /* SDCLK1 Run Control/Status */
+#define MDREFR_E1PIN (1 << 15) /* SDCKE1 Level Control/Status */
+#define MDREFR_K0DB2 (1 << 14) /* SDCLK0 Divide by 2 Control/Status */
+#define MDREFR_K0RUN (1 << 13) /* SDCLK0 Run Control/Status */
+#define MDREFR_E0PIN (1 << 12) /* SDCKE0 Level Control/Status */
+#define MDREFR_DB2_MASK (MDREFR_K2DB2 | MDREFR_K1DB2)
+#define MDREFR_DRI_MASK 0xFFF
+
+static DEFINE_SPINLOCK(pxa_clk_lock);
+
+static struct clk *pxa_clocks[CLK_MAX];
+static struct clk_onecell_data onecell_data = {
+ .clks = pxa_clocks,
+ .clk_num = CLK_MAX,
+};
+
+struct pxa_clk {
+ struct clk_hw hw;
+ struct clk_fixed_factor lp;
+ struct clk_fixed_factor hp;
+ struct clk_gate gate;
+ bool (*is_in_low_power)(void);
+};
+
+#define to_pxa_clk(_hw) container_of(_hw, struct pxa_clk, hw)
+
+static unsigned long cken_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct pxa_clk *pclk = to_pxa_clk(hw);
+ struct clk_fixed_factor *fix;
+
+ if (!pclk->is_in_low_power || pclk->is_in_low_power())
+ fix = &pclk->lp;
+ else
+ fix = &pclk->hp;
+ __clk_hw_set_clk(&fix->hw, hw);
+ return clk_fixed_factor_ops.recalc_rate(&fix->hw, parent_rate);
+}
+
+static const struct clk_ops cken_rate_ops = {
+ .recalc_rate = cken_recalc_rate,
+};
+
+static u8 cken_get_parent(struct clk_hw *hw)
+{
+ struct pxa_clk *pclk = to_pxa_clk(hw);
+
+ if (!pclk->is_in_low_power)
+ return 0;
+ return pclk->is_in_low_power() ? 0 : 1;
+}
+
+static const struct clk_ops cken_mux_ops = {
+ .get_parent = cken_get_parent,
+ .set_parent = dummy_clk_set_parent,
+};
+
+void __init clkdev_pxa_register(int ckid, const char *con_id,
+ const char *dev_id, struct clk *clk)
+{
+ if (!IS_ERR(clk) && (ckid != CLK_NONE))
+ pxa_clocks[ckid] = clk;
+ if (!IS_ERR(clk))
+ clk_register_clkdev(clk, con_id, dev_id);
+}
+
+int __init clk_pxa_cken_init(const struct desc_clk_cken *clks,
+ int nb_clks, void __iomem *clk_regs)
+{
+ int i;
+ struct pxa_clk *pxa_clk;
+ struct clk *clk;
+
+ for (i = 0; i < nb_clks; i++) {
+ pxa_clk = kzalloc(sizeof(*pxa_clk), GFP_KERNEL);
+ if (!pxa_clk)
+ return -ENOMEM;
+ pxa_clk->is_in_low_power = clks[i].is_in_low_power;
+ pxa_clk->lp = clks[i].lp;
+ pxa_clk->hp = clks[i].hp;
+ pxa_clk->gate = clks[i].gate;
+ pxa_clk->gate.reg = clk_regs + clks[i].cken_reg;
+ pxa_clk->gate.lock = &pxa_clk_lock;
+ clk = clk_register_composite(NULL, clks[i].name,
+ clks[i].parent_names, 2,
+ &pxa_clk->hw, &cken_mux_ops,
+ &pxa_clk->hw, &cken_rate_ops,
+ &pxa_clk->gate.hw, &clk_gate_ops,
+ clks[i].flags);
+ clkdev_pxa_register(clks[i].ckid, clks[i].con_id,
+ clks[i].dev_id, clk);
+ }
+ return 0;
+}
+
+void __init clk_pxa_dt_common_init(struct device_node *np)
+{
+ of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data);
+}
+
+void pxa2xx_core_turbo_switch(bool on)
+{
+ unsigned long flags;
+ unsigned int unused, clkcfg;
+
+ local_irq_save(flags);
+
+ asm("mrc p14, 0, %0, c6, c0, 0" : "=r" (clkcfg));
+ clkcfg &= ~CLKCFG_TURBO & ~CLKCFG_HALFTURBO;
+ if (on)
+ clkcfg |= CLKCFG_TURBO;
+ clkcfg |= CLKCFG_FCS;
+
+ asm volatile(
+ " b 2f\n"
+ " .align 5\n"
+ "1: mcr p14, 0, %1, c6, c0, 0\n"
+ " b 3f\n"
+ "2: b 1b\n"
+ "3: nop\n"
+ : "=&r" (unused) : "r" (clkcfg));
+
+ local_irq_restore(flags);
+}
+
+void pxa2xx_cpll_change(struct pxa2xx_freq *freq,
+ u32 (*mdrefr_dri)(unsigned int),
+ void __iomem *cccr)
+{
+ unsigned int clkcfg = freq->clkcfg;
+ unsigned int unused, preset_mdrefr, postset_mdrefr;
+ unsigned long flags;
+ void __iomem *mdrefr = pxa_smemc_get_mdrefr();
+
+ local_irq_save(flags);
+
+ /* Calculate the next MDREFR. If we're slowing down the SDRAM clock
+ * we need to preset the smaller DRI before the change. If we're
+ * speeding up we need to set the larger DRI value after the change.
+ */
+ preset_mdrefr = postset_mdrefr = readl(mdrefr);
+ if ((preset_mdrefr & MDREFR_DRI_MASK) > mdrefr_dri(freq->membus_khz)) {
+ preset_mdrefr = (preset_mdrefr & ~MDREFR_DRI_MASK);
+ preset_mdrefr |= mdrefr_dri(freq->membus_khz);
+ }
+ postset_mdrefr =
+ (postset_mdrefr & ~MDREFR_DRI_MASK) |
+ mdrefr_dri(freq->membus_khz);
+
+ /* If we're dividing the memory clock by two for the SDRAM clock, this
+ * must be set prior to the change. Clearing the divide must be done
+ * after the change.
+ */
+ if (freq->div2) {
+ preset_mdrefr |= MDREFR_DB2_MASK;
+ postset_mdrefr |= MDREFR_DB2_MASK;
+ } else {
+ postset_mdrefr &= ~MDREFR_DB2_MASK;
+ }
+
+ /* Set new the CCCR and prepare CLKCFG */
+ writel(freq->cccr, cccr);
+
+ asm volatile(
+ " ldr r4, [%1]\n"
+ " b 2f\n"
+ " .align 5\n"
+ "1: str %3, [%1] /* preset the MDREFR */\n"
+ " mcr p14, 0, %2, c6, c0, 0 /* set CLKCFG[FCS] */\n"
+ " str %4, [%1] /* postset the MDREFR */\n"
+ " b 3f\n"
+ "2: b 1b\n"
+ "3: nop\n"
+ : "=&r" (unused)
+ : "r" (mdrefr), "r" (clkcfg), "r" (preset_mdrefr),
+ "r" (postset_mdrefr)
+ : "r4", "r5");
+
+ local_irq_restore(flags);
+}
+
+int pxa2xx_determine_rate(struct clk_rate_request *req,
+ struct pxa2xx_freq *freqs, int nb_freqs)
+{
+ int i, closest_below = -1, closest_above = -1;
+ unsigned long rate;
+
+ for (i = 0; i < nb_freqs; i++) {
+ rate = freqs[i].cpll;
+ if (rate == req->rate)
+ break;
+ if (rate < req->min_rate)
+ continue;
+ if (rate > req->max_rate)
+ continue;
+ if (rate <= req->rate)
+ closest_below = i;
+ if ((rate >= req->rate) && (closest_above == -1))
+ closest_above = i;
+ }
+
+ req->best_parent_hw = NULL;
+
+ if (i < nb_freqs) {
+ rate = req->rate;
+ } else if (closest_below >= 0) {
+ rate = freqs[closest_below].cpll;
+ } else if (closest_above >= 0) {
+ rate = freqs[closest_above].cpll;
+ } else {
+ pr_debug("%s(rate=%lu) no match\n", __func__, req->rate);
+ return -EINVAL;
+ }
+
+ pr_debug("%s(rate=%lu) rate=%lu\n", __func__, req->rate, rate);
+ req->rate = rate;
+
+ return 0;
+}