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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-10 11:42:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-10 11:42:19 -0700
commit6f630784cc0d92fb58ea326e2bc01aa056279ecb (patch)
treef836a2bb79463d7634f92aa51d324bd548a3832b /drivers/clk/tegra/clk-tegra124-emc.c
parent3a2a8751742133a7bbc49b9d1bcbd52e212edff6 (diff)
parent9ac1eafa885a9b2d3becd4f2e622829b1f5b9b86 (diff)
Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux
Pull clk updates from Stephen Boyd: "This time around we have four lines of diff in the core framework, removing a function that isn't used anymore. Otherwise the main new thing for the common clk framework is that it is selectable in the Kconfig language now. Hopefully this will let clk drivers and clk consumers be testable on more than the architectures that support the clk framework. The goal is to introduce some Kunit tests for the framework. Outside of the core framework we have the usual set of various driver updates and non-critical fixes. The dirstat shows that the new Baikal-T1 driver is the largest addition this time around in terms of lines of code. After that the x86 (Intel), Qualcomm, and Mediatek drivers introduce many lines to support new or upcoming SoCs. After that the dirstat shows the usual suspects working on their SoC support by fixing minor bugs, correcting data and converting some of their DT bindings to YAML. Core: - Allow the COMMON_CLK config to be selectable New Drivers: - Clk driver for Baikal-T1 SoCs - Mediatek MT6765 clock support - Support for Intel Agilex clks - Add support for X1830 and X1000 Ingenic SoC clk controllers - Add support for the new Renesas RZ/G1H (R8A7742) SoC - Add support for Qualcomm's MSM8939 Generic Clock Controller Updates: - Support IDT VersaClock 5P49V5925 - Bunch of updates for HSDK clock generation unit (CGU) driver - Start making audio and GPU clks work on Marvell MMP2/MMP3 SoCs - Add some GPU, NPU, and UFS clks to Qualcomm SM8150 driver - Enable supply regulators for GPU gdscs on Qualcomm SoCs - Add support for Si5342, Si5344 and Si5345 chips - Support custom flags in Xilinx zynq firmware - Various small fixes to the Xilinx clk driver - A single minor rounding fix for the legacy Allwinner clock support - A few patches from Abel Vesa as preparation of adding audiomix clock support on i.MX - A couple of cleanups from Anson Huang for i.MX clk-sscg-pll and clk-pllv3 drivers - Drop dependency on ARM64 for i.MX8M clock driver, to support aarch32 mode on aarch64 hardware - A series from Peng Fan to improve i.MX8M clock drivers, using composite clock for core and bus clk slice - Set a better parent clock for flexcan on i.MX6UL to support CiA102 defined bit rates - A couple changes for EMC frequency scaling on Tegra210 - Support for CPU frequency scaling on Tegra20/Tegra30 - New clk gate for CSI test pattern generator on Tegra210 - Regression fixes for Samsung exynos542x and exynos5433 SoCs - Use of fallthrough; attribute for Samsung s3c24xx - Updates and fixup HDMI and video clocks on Meson8b - Fixup reset polarity on Meson8b - Fix GPU glitch free mux switch on Meson gx and g12 - A minor fix for the currently unused suspend/resume handling on Renesas RZ/A1 and RZ/A2 - Two more conversions of Renesas DT bindings to json-schema - Add support for the USB 2.0 clock selector on Renesas R-Car M3-W+" * tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (155 commits) clk: mediatek: Remove ifr{0,1}_cfg_regs structures clk: baikal-t1: remove redundant assignment to variable 'divider' clk: baikal-t1: fix spelling mistake "Uncompatible" -> "Incompatible" dt-bindings: clock: Add a missing include to MMP Audio Clock binding dt: Add bindings for IDT VersaClock 5P49V5925 clk: vc5: Add support for IDT VersaClock 5P49V6965 clk: Add Baikal-T1 CCU Dividers driver clk: Add Baikal-T1 CCU PLLs driver dt-bindings: clk: Add Baikal-T1 CCU Dividers binding dt-bindings: clk: Add Baikal-T1 CCU PLLs binding clk: mediatek: assign the initial value to clk_init_data of mtk_mux clk: mediatek: Add MT6765 clock support clk: mediatek: add mt6765 clock IDs dt-bindings: clock: mediatek: document clk bindings vcodecsys for Mediatek MT6765 SoC dt-bindings: clock: mediatek: document clk bindings mipi0a for Mediatek MT6765 SoC dt-bindings: clock: mediatek: document clk bindings for Mediatek MT6765 SoC CLK: HSDK: CGU: add support for 148.5MHz clock CLK: HSDK: CGU: support PLL bypassing CLK: HSDK: CGU: check if PLL is bypassed first clk: clk-si5341: Add support for the Si5345 series ...
Diffstat (limited to 'drivers/clk/tegra/clk-tegra124-emc.c')
-rw-r--r--drivers/clk/tegra/clk-tegra124-emc.c540
1 files changed, 540 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-tegra124-emc.c b/drivers/clk/tegra/clk-tegra124-emc.c
new file mode 100644
index 000000000000..745f9faa98d8
--- /dev/null
+++ b/drivers/clk/tegra/clk-tegra124-emc.c
@@ -0,0 +1,540 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * drivers/clk/tegra/clk-emc.c
+ *
+ * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Author:
+ * Mikko Perttunen <mperttunen@nvidia.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/delay.h>
+#include <linux/io.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/emc.h>
+
+#include "clk.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_DIVISOR(x) (((x) & CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_MASK) << \
+ CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR_SHIFT)
+
+#define CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT 29
+#define CLK_SOURCE_EMC_EMC_2X_CLK_SRC_MASK 0x7
+#define CLK_SOURCE_EMC_EMC_2X_CLK_SRC(x) (((x) & CLK_SOURCE_EMC_EMC_2X_CLK_SRC_MASK) << \
+ CLK_SOURCE_EMC_EMC_2X_CLK_SRC_SHIFT)
+
+static const char * const 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
+
+static 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_clk_emc {
+ struct clk_hw hw;
+ void __iomem *clk_regs;
+ struct clk *prev_parent;
+ bool changing_timing;
+
+ struct device_node *emc_node;
+ struct tegra_emc *emc;
+
+ int num_timings;
+ struct emc_timing *timings;
+ spinlock_t *lock;
+};
+
+/* Common clock framework callback implementations */
+
+static unsigned long emc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct tegra_clk_emc *tegra;
+ u32 val, div;
+
+ tegra = container_of(hw, struct tegra_clk_emc, hw);
+
+ /*
+ * CCF wrongly assumes that the parent won't change during set_rate,
+ * so get the parent rate explicitly.
+ */
+ parent_rate = clk_hw_get_rate(clk_hw_get_parent(hw));
+
+ 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.
+ */
+static int emc_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ struct tegra_clk_emc *tegra;
+ u8 ram_code = tegra_read_ram_code();
+ struct emc_timing *timing = NULL;
+ int i, k, t;
+
+ tegra = container_of(hw, struct tegra_clk_emc, hw);
+
+ for (k = 0; k < tegra->num_timings; k++) {
+ if (tegra->timings[k].ram_code == ram_code)
+ break;
+ }
+
+ for (t = k; t < tegra->num_timings; t++) {
+ if (tegra->timings[t].ram_code != ram_code)
+ break;
+ }
+
+ for (i = k; i < t; i++) {
+ timing = tegra->timings + i;
+
+ if (timing->rate < req->rate && i != t - 1)
+ continue;
+
+ if (timing->rate > req->max_rate) {
+ i = max(i, k + 1);
+ req->rate = tegra->timings[i - 1].rate;
+ return 0;
+ }
+
+ if (timing->rate < req->min_rate)
+ continue;
+
+ req->rate = timing->rate;
+ return 0;
+ }
+
+ if (timing) {
+ req->rate = timing->rate;
+ return 0;
+ }
+
+ req->rate = clk_hw_get_rate(hw);
+ return 0;
+}
+
+static u8 emc_get_parent(struct clk_hw *hw)
+{
+ struct tegra_clk_emc *tegra;
+ u32 val;
+
+ tegra = container_of(hw, struct tegra_clk_emc, hw);
+
+ 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 struct tegra_emc *emc_ensure_emc_driver(struct tegra_clk_emc *tegra)
+{
+ struct platform_device *pdev;
+
+ if (tegra->emc)
+ return tegra->emc;
+
+ if (!tegra->emc_node)
+ return NULL;
+
+ pdev = of_find_device_by_node(tegra->emc_node);
+ if (!pdev) {
+ pr_err("%s: could not get external memory controller\n",
+ __func__);
+ return NULL;
+ }
+
+ of_node_put(tegra->emc_node);
+ tegra->emc_node = NULL;
+
+ tegra->emc = platform_get_drvdata(pdev);
+ if (!tegra->emc) {
+ pr_err("%s: cannot find EMC driver\n", __func__);
+ return NULL;
+ }
+
+ return tegra->emc;
+}
+
+static int emc_set_timing(struct tegra_clk_emc *tegra,
+ struct emc_timing *timing)
+{
+ int err;
+ u8 div;
+ u32 car_value;
+ unsigned long flags = 0;
+ struct tegra_emc *emc = emc_ensure_emc_driver(tegra);
+
+ if (!emc)
+ return -ENOENT;
+
+ 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) {
+ WARN_ONCE(1, "parent %s rate mismatch %lu %lu\n",
+ __clk_get_name(timing->parent),
+ clk_get_rate(timing->parent),
+ timing->parent_rate);
+ 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;
+
+ err = tegra_emc_prepare_timing_change(emc, timing->rate);
+ if (err)
+ return err;
+
+ spin_lock_irqsave(tegra->lock, flags);
+
+ car_value = readl(tegra->clk_regs + CLK_SOURCE_EMC);
+
+ car_value &= ~CLK_SOURCE_EMC_EMC_2X_CLK_SRC(~0);
+ car_value |= CLK_SOURCE_EMC_EMC_2X_CLK_SRC(timing->parent_index);
+
+ car_value &= ~CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR(~0);
+ car_value |= CLK_SOURCE_EMC_EMC_2X_CLK_DIVISOR(div);
+
+ writel(car_value, tegra->clk_regs + CLK_SOURCE_EMC);
+
+ spin_unlock_irqrestore(tegra->lock, flags);
+
+ tegra_emc_complete_timing_change(emc, timing->rate);
+
+ clk_hw_reparent(&tegra->hw, __clk_get_hw(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_clk_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)
+ break;
+
+ 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)
+ break;
+
+ 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_clk_emc *tegra;
+ struct emc_timing *timing = NULL;
+ int i, err;
+ u32 ram_code = tegra_read_ram_code();
+
+ tegra = container_of(hw, struct tegra_clk_emc, hw);
+
+ if (clk_hw_get_rate(hw) == 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_clk_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 %pOF: failed to read rate\n", node);
+ return err;
+ }
+
+ timing->rate = tmp;
+
+ err = of_property_read_u32(node, "nvidia,parent-clock-frequency", &tmp);
+ if (err) {
+ pr_err("timing %pOF: failed to read parent rate\n", node);
+ return err;
+ }
+
+ timing->parent_rate = tmp;
+
+ timing->parent = of_clk_get_by_name(node, "emc-parent");
+ if (IS_ERR(timing->parent)) {
+ pr_err("timing %pOF: failed to get parent clock\n", node);
+ return PTR_ERR(timing->parent);
+ }
+
+ timing->parent_index = 0xff;
+ i = match_string(emc_parent_clk_names, ARRAY_SIZE(emc_parent_clk_names),
+ __clk_get_name(timing->parent));
+ if (i < 0) {
+ pr_err("timing %pOF: %s is not a valid parent\n",
+ node, __clk_get_name(timing->parent));
+ clk_put(timing->parent);
+ return -EINVAL;
+ }
+
+ timing->parent_index = i;
+ 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_clk_emc *tegra,
+ struct device_node *node,
+ u32 ram_code)
+{
+ struct emc_timing *timings_ptr;
+ struct device_node *child;
+ int child_count = of_get_child_count(node);
+ int i = 0, err;
+ size_t size;
+
+ size = (tegra->num_timings + child_count) * sizeof(struct emc_timing);
+
+ tegra->timings = krealloc(tegra->timings, size, GFP_KERNEL);
+ if (!tegra->timings)
+ return -ENOMEM;
+
+ timings_ptr = tegra->timings + tegra->num_timings;
+ tegra->num_timings += child_count;
+
+ for_each_child_of_node(node, child) {
+ struct emc_timing *timing = timings_ptr + (i++);
+
+ err = load_one_timing_from_dt(tegra, timing, child);
+ if (err) {
+ of_node_put(child);
+ return err;
+ }
+
+ timing->ram_code = ram_code;
+ }
+
+ sort(timings_ptr, child_count, sizeof(struct emc_timing),
+ cmp_timings, NULL);
+
+ return 0;
+}
+
+static const struct clk_ops tegra_clk_emc_ops = {
+ .recalc_rate = emc_recalc_rate,
+ .determine_rate = emc_determine_rate,
+ .set_rate = emc_set_rate,
+ .get_parent = emc_get_parent,
+};
+
+struct clk *tegra_clk_register_emc(void __iomem *base, struct device_node *np,
+ spinlock_t *lock)
+{
+ struct tegra_clk_emc *tegra;
+ struct clk_init_data init;
+ struct device_node *node;
+ u32 node_ram_code;
+ struct clk *clk;
+ int err;
+
+ tegra = kcalloc(1, sizeof(*tegra), GFP_KERNEL);
+ if (!tegra)
+ return ERR_PTR(-ENOMEM);
+
+ tegra->clk_regs = base;
+ tegra->lock = lock;
+
+ tegra->num_timings = 0;
+
+ for_each_child_of_node(np, node) {
+ err = of_property_read_u32(node, "nvidia,ram-code",
+ &node_ram_code);
+ if (err)
+ continue;
+
+ /*
+ * Store timings for all ram codes as we cannot read the
+ * fuses until the apbmisc driver is loaded.
+ */
+ err = load_timings_from_dt(tegra, node, node_ram_code);
+ if (err) {
+ of_node_put(node);
+ return ERR_PTR(err);
+ }
+ }
+
+ if (tegra->num_timings == 0)
+ pr_warn("%s: no memory timings registered\n", __func__);
+
+ tegra->emc_node = of_parse_phandle(np,
+ "nvidia,external-memory-controller", 0);
+ if (!tegra->emc_node)
+ pr_warn("%s: couldn't find node for EMC driver\n", __func__);
+
+ init.name = "emc";
+ init.ops = &tegra_clk_emc_ops;
+ init.flags = CLK_IS_CRITICAL;
+ 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_hw_get_parent_by_index(
+ &tegra->hw, emc_get_parent(&tegra->hw))->clk;
+ tegra->changing_timing = false;
+
+ /* Allow debugging tools to see the EMC clock */
+ clk_register_clkdev(clk, "emc", "tegra-clk-debug");
+
+ return clk;
+};