@@ -14,4 +14,4 @@ obj-y += clk-tegra-super-gen4.o
obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += clk-tegra20.o
obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += clk-tegra30.o
obj-$(CONFIG_ARCH_TEGRA_114_SOC) += clk-tegra114.o
-obj-$(CONFIG_ARCH_TEGRA_124_SOC) += clk-tegra124.o
+obj-$(CONFIG_ARCH_TEGRA_124_SOC) += clk-tegra124.o clk-emc.o
new file mode 100644
@@ -0,0 +1,454 @@
+/*
+ * drivers/clk/tegra/clk-emc.c
+ *
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Author:
+ * Mikko Perttunen <mperttunen@nvidia.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/sort.h>
+#include <linux/string.h>
+
+#include <soc/tegra/fuse.h>
+#include <soc/tegra/memory.h>
+
+#define CLK_SOURCE_EMC 0x19c
+#define CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_SHIFT 0
+#define CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_MASK 0xff
+#define CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT 29
+#define CLK_SOURCE_EMC_EMC_2X_CLK_SRC_MASK 0x7
+
+const char *emc_parent_clk_names[] = {
+ "pll_m", "pll_c", "pll_p", "clk_m", "pll_m_ud",
+ "pll_c2", "pll_c3", "pll_c_ud"
+};
+
+/* List of clock sources for various parents the EMC clock can have.
+ * When we change the timing to a timing with a parent that has the same
+ * clock source as the current parent, we must first change to a backup
+ * timing that has a different clock source.
+ */
+
+#define EMC_SRC_PLL_M 0
+#define EMC_SRC_PLL_C 1
+#define EMC_SRC_PLL_P 2
+#define EMC_SRC_CLK_M 3
+#define EMC_SRC_PLL_C2 4
+#define EMC_SRC_PLL_C3 5
+const char emc_parent_clk_sources[] = {
+ EMC_SRC_PLL_M, EMC_SRC_PLL_C, EMC_SRC_PLL_P, EMC_SRC_CLK_M,
+ EMC_SRC_PLL_M, EMC_SRC_PLL_C2, EMC_SRC_PLL_C3, EMC_SRC_PLL_C
+};
+
+struct emc_timing {
+ unsigned long rate, parent_rate;
+ u8 parent_index;
+ struct clk *parent;
+ u32 ram_code;
+};
+
+struct tegra_emc {
+ struct clk_hw hw;
+ void __iomem *clk_regs;
+ struct clk *prev_parent;
+ bool changing_timing;
+
+ int num_timings;
+ struct emc_timing *timings;
+};
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Common clock framework callback implementations *
+ * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+unsigned long emc_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct tegra_emc *tegra = container_of(hw, struct tegra_emc, hw);
+ u32 val, div;
+
+ /* CCF wrongly assumes that the parent won't change during set_rate,
+ * so get the parent rate explicitly.
+ */
+ parent_rate = __clk_get_rate(__clk_get_parent(hw->clk));
+
+ val = readl(tegra->clk_regs + CLK_SOURCE_EMC);
+ div = val & CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_MASK;
+
+ return parent_rate / (div + 2) * 2;
+}
+
+/* Rounds up unless no higher rate exists, in which case down. This way is
+ * safer since things have EMC rate floors. Also don't touch parent_rate
+ * since we don't want the CCF to play with our parent clocks.
+ */
+long emc_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct tegra_emc *tegra = container_of(hw, struct tegra_emc, hw);
+ u8 ram_code = tegra_read_ram_code();
+ struct emc_timing *timing;
+ int i;
+
+ /* Returning the original rate will lead to a more sensible error
+ * message when emc_set_rate fails.
+ */
+ if (tegra->num_timings == 0)
+ return rate;
+
+ for (i = 0; i < tegra->num_timings; ++i) {
+ timing = tegra->timings + i;
+ if (timing->ram_code != ram_code)
+ continue;
+
+ if (timing->rate >= rate)
+ return timing->rate;
+ }
+
+ return tegra->timings[tegra->num_timings - 1].rate;
+}
+
+u8 emc_get_parent(struct clk_hw *hw)
+{
+ struct tegra_emc *tegra = container_of(hw, struct tegra_emc, hw);
+ u32 val;
+
+ val = readl(tegra->clk_regs + CLK_SOURCE_EMC);
+
+ return (val >> CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT)
+ & CLK_SOURCE_EMC_EMC_2X_CLK_SRC_MASK;
+}
+
+static int emc_set_timing(struct tegra_emc *tegra, struct emc_timing *timing)
+{
+ int err;
+ u8 div;
+ u32 car_value;
+
+ pr_debug("going to rate %ld prate %ld p %s\n",
+ timing->rate, timing->parent_rate,
+ __clk_get_name(timing->parent));
+
+ if (emc_get_parent(&tegra->hw) == timing->parent_index &&
+ clk_get_rate(timing->parent) != timing->parent_rate) {
+ BUG();
+ return -EINVAL;
+ }
+
+ tegra->changing_timing = true;
+
+ err = clk_set_rate(timing->parent, timing->parent_rate);
+ if (err) {
+ pr_err("cannot change parent %s rate to %ld: %d\n",
+ __clk_get_name(timing->parent),
+ timing->parent_rate, err);
+
+ return err;
+ }
+
+ err = clk_prepare_enable(timing->parent);
+ if (err) {
+ pr_err("cannot enable parent clock: %d\n", err);
+ return err;
+ }
+
+ div = timing->parent_rate / (timing->rate / 2) - 2;
+
+ car_value = 0;
+ car_value |= timing->parent_index <<
+ CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT;
+ car_value |= div << CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_SHIFT;
+
+ tegra_emc_prepare_timing_change(timing->rate);
+
+ writel(car_value, tegra->clk_regs + CLK_SOURCE_EMC);
+
+ tegra_emc_complete_timing_change(timing->rate);
+
+ __clk_reparent(tegra->hw.clk, timing->parent);
+ clk_disable_unprepare(tegra->prev_parent);
+
+ tegra->prev_parent = timing->parent;
+ tegra->changing_timing = false;
+
+ return 0;
+}
+
+/* Get backup timing to use as an intermediate step when a change between
+ * two timings with the same clock source has been requested. First try to
+ * find a timing with a higher clock rate to avoid a rate below any set rate
+ * floors. If that is not possible, find a lower rate.
+ */
+static struct emc_timing *get_backup_timing(struct tegra_emc *tegra,
+ int timing_index)
+{
+ int i;
+ u32 ram_code = tegra_read_ram_code();
+ struct emc_timing *timing;
+
+ for (i = timing_index+1; i < tegra->num_timings; ++i) {
+ timing = tegra->timings + i;
+ if (timing->ram_code != ram_code)
+ continue;
+
+ if (emc_parent_clk_sources[timing->parent_index] !=
+ emc_parent_clk_sources[
+ tegra->timings[timing_index].parent_index])
+ return timing;
+ }
+
+ for (i = timing_index-1; i >= 0; --i) {
+ timing = tegra->timings + i;
+ if (timing->ram_code != ram_code)
+ continue;
+
+ if (emc_parent_clk_sources[timing->parent_index] !=
+ emc_parent_clk_sources[
+ tegra->timings[timing_index].parent_index])
+ return timing;
+ }
+
+ return NULL;
+}
+
+static int emc_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct tegra_emc *tegra = container_of(hw, struct tegra_emc, hw);
+ struct emc_timing *timing = NULL;
+ int i, err;
+ u32 ram_code = tegra_read_ram_code();
+
+ if (__clk_get_rate(hw->clk) == rate)
+ return 0;
+
+ /* When emc_set_timing changes the parent rate, CCF will propagate
+ * that downward to us, so ignore any set_rate calls while a rate
+ * change is already going on.
+ */
+ if (tegra->changing_timing)
+ return 0;
+
+ for (i = 0; i < tegra->num_timings; ++i) {
+ if (tegra->timings[i].rate == rate &&
+ tegra->timings[i].ram_code == ram_code) {
+ timing = tegra->timings + i;
+ break;
+ }
+ }
+
+ if (!timing) {
+ pr_err("cannot switch to rate %ld without emc table\n", rate);
+ return -EINVAL;
+ }
+
+ if (emc_parent_clk_sources[emc_get_parent(hw)] ==
+ emc_parent_clk_sources[timing->parent_index] &&
+ clk_get_rate(timing->parent) != timing->parent_rate) {
+ /* Parent clock source not changed but parent rate has changed,
+ * need to temporarily switch to another parent
+ */
+
+ struct emc_timing *backup_timing;
+
+ backup_timing = get_backup_timing(tegra, i);
+ if (!backup_timing) {
+ pr_err("cannot find backup timing\n");
+ return -EINVAL;
+ }
+
+ pr_debug("using %ld as backup rate when going to %ld\n",
+ backup_timing->rate, rate);
+
+ err = emc_set_timing(tegra, backup_timing);
+ if (err) {
+ pr_err("cannot set backup timing: %d\n", err);
+ return err;
+ }
+ }
+
+ return emc_set_timing(tegra, timing);
+}
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Initialization and deinitialization *
+ * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+static int load_one_timing_from_dt(struct tegra_emc *tegra,
+ struct emc_timing *timing,
+ struct device_node *node)
+{
+ int err, i;
+ u32 tmp;
+
+ err = of_property_read_u32(node, "clock-frequency", &tmp);
+ if (err) {
+ pr_err("timing %s: failed to read rate\n", node->full_name);
+ return err;
+ }
+
+ timing->rate = tmp;
+
+ err = of_property_read_u32(node, "nvidia,parent-clock-frequency", &tmp);
+ if (err) {
+ pr_err("timing %s: failed to read parent rate\n",
+ node->full_name);
+ return err;
+ }
+
+ timing->parent_rate = tmp;
+
+ timing->parent = of_clk_get_by_name(node, "emc-parent");
+ if (IS_ERR(timing->parent)) {
+ pr_err("timing %s: failed to get parent clock\n",
+ node->full_name);
+ return PTR_ERR(timing->parent);
+ }
+
+ timing->parent_index = 0xff;
+ for (i = 0; i < ARRAY_SIZE(emc_parent_clk_names); ++i) {
+ if (!strcmp(emc_parent_clk_names[i],
+ __clk_get_name(timing->parent))) {
+ timing->parent_index = i;
+ break;
+ }
+ }
+ if (timing->parent_index == 0xff) {
+ pr_err("timing %s: %s is not a valid parent\n",
+ node->full_name, __clk_get_name(timing->parent));
+ clk_put(timing->parent);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int cmp_timings(const void *_a, const void *_b)
+{
+ const struct emc_timing *a = _a;
+ const struct emc_timing *b = _b;
+
+ if (a->rate < b->rate)
+ return -1;
+ else if (a->rate == b->rate)
+ return 0;
+ else
+ return 1;
+}
+
+static int load_timings_from_dt(struct tegra_emc *tegra,
+ struct device_node *node,
+ u32 ram_code)
+{
+ struct device_node *child;
+ int child_count = of_get_child_count(node);
+ int i = 0, err;
+
+ tegra->timings = kcalloc(child_count, sizeof(struct emc_timing),
+ GFP_KERNEL);
+ if (!tegra->timings)
+ return -ENOMEM;
+
+ tegra->num_timings = child_count;
+
+ for_each_child_of_node(node, child) {
+ struct emc_timing *timing = tegra->timings + (i++);
+
+ err = load_one_timing_from_dt(tegra, timing, child);
+ if (err)
+ return err;
+
+ timing->ram_code = ram_code;
+ }
+
+ sort(tegra->timings, tegra->num_timings, sizeof(struct emc_timing),
+ cmp_timings, NULL);
+
+ return 0;
+}
+
+const struct clk_ops tegra_clk_emc_ops = {
+ .recalc_rate = emc_recalc_rate,
+ .round_rate = emc_round_rate,
+ .set_rate = emc_set_rate,
+ .get_parent = emc_get_parent,
+};
+
+struct clk *tegra_emc_init(struct device_node *np, void __iomem *clk_regs)
+{
+ struct tegra_emc *tegra;
+ struct clk *clk;
+ struct clk_init_data init;
+ struct device_node *node;
+ u32 node_ram_code;
+ int err;
+
+ tegra = kcalloc(1, sizeof(*tegra), GFP_KERNEL);
+ if (!tegra)
+ return ERR_PTR(-ENOMEM);
+
+ tegra->clk_regs = clk_regs;
+
+ tegra->num_timings = 0;
+
+ for_each_child_of_node(np, node) {
+ if (strcmp(node->name, "emc-timings"))
+ continue;
+
+ err = of_property_read_u32(node, "nvidia,ram-code",
+ &node_ram_code);
+ if (err) {
+ pr_warn("skipping timing without ram-code\n");
+ continue;
+ }
+
+ err = load_timings_from_dt(tegra, node, node_ram_code);
+ if (err)
+ return ERR_PTR(err);
+ break;
+ }
+
+ if (tegra->num_timings == 0)
+ pr_warn("no memory timings registered\n");
+
+ init.name = "emc";
+ init.ops = &tegra_clk_emc_ops;
+ init.flags = 0;
+ init.parent_names = emc_parent_clk_names;
+ init.num_parents = ARRAY_SIZE(emc_parent_clk_names);
+
+ tegra->hw.init = &init;
+
+ clk = clk_register(NULL, &tegra->hw);
+ if (IS_ERR(clk))
+ return clk;
+
+ tegra->prev_parent = clk_get_parent_by_index(
+ tegra->hw.clk, emc_get_parent(&tegra->hw));
+ tegra->changing_timing = false;
+
+ /* Allow debugging tools to see the EMC clock */
+ clk_register_clkdev(clk, "emc", "tegra-clk-debug");
+
+ clk_prepare_enable(clk);
+
+ return clk;
+};
@@ -1383,7 +1383,6 @@ static struct tegra_clk_init_table init_table[] __initdata = {
{TEGRA124_CLK_XUSB_HOST_SRC, TEGRA124_CLK_PLL_RE_OUT, 112000000, 0},
{TEGRA124_CLK_SATA, TEGRA124_CLK_PLL_P, 104000000, 0},
{TEGRA124_CLK_SATA_OOB, TEGRA124_CLK_PLL_P, 204000000, 0},
- {TEGRA124_CLK_EMC, TEGRA124_CLK_CLK_MAX, 0, 1},
{TEGRA124_CLK_CCLK_G, TEGRA124_CLK_CLK_MAX, 0, 1},
{TEGRA124_CLK_MSELECT, TEGRA124_CLK_CLK_MAX, 0, 1},
{TEGRA124_CLK_CSITE, TEGRA124_CLK_CLK_MAX, 0, 1},
@@ -1439,6 +1438,9 @@ static void __init tegra124_clock_init(struct device_node *np)
tegra_super_clk_gen4_init(clk_base, pmc_base, tegra124_clks,
&pll_x_params);
tegra_add_of_provider(np);
+
+ clks[TEGRA124_CLK_EMC] = tegra_emc_init(np, clk_base);
+
tegra_register_devclks(devclks, ARRAY_SIZE(devclks));
tegra_clk_apply_init_table = tegra124_clock_apply_init_table;
@@ -623,6 +623,8 @@ void tegra_super_clk_gen4_init(void __iomem *clk_base,
void __iomem *pmc_base, struct tegra_clk *tegra_clks,
struct tegra_clk_pll_params *pll_params);
+struct clk *tegra_emc_init(struct device_node *np, void __iomem *clk_regs);
+
void tegra114_clock_tune_cpu_trimmers_high(void);
void tegra114_clock_tune_cpu_trimmers_low(void);
void tegra114_clock_tune_cpu_trimmers_init(void);