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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/memory/da8xx-ddrctl.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/memory/da8xx-ddrctl.c')
-rw-r--r--drivers/memory/da8xx-ddrctl.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/drivers/memory/da8xx-ddrctl.c b/drivers/memory/da8xx-ddrctl.c
new file mode 100644
index 000000000..872addd0e
--- /dev/null
+++ b/drivers/memory/da8xx-ddrctl.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TI da8xx DDR2/mDDR controller driver
+ *
+ * Copyright (C) 2016 BayLibre SAS
+ *
+ * Author:
+ * Bartosz Golaszewski <bgolaszewski@baylibre.com>
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+
+/*
+ * REVISIT: Linux doesn't have a good framework for the kind of performance
+ * knobs this driver controls. We can't use device tree properties as it deals
+ * with hardware configuration rather than description. We also don't want to
+ * commit to maintaining some random sysfs attributes.
+ *
+ * For now we just hardcode the register values for the boards that need
+ * some changes (as is the case for the LCD controller on da850-lcdk - the
+ * first board we support here). When linux gets an appropriate framework,
+ * we'll easily convert the driver to it.
+ */
+
+struct da8xx_ddrctl_config_knob {
+ const char *name;
+ u32 reg;
+ u32 mask;
+ u32 shift;
+};
+
+static const struct da8xx_ddrctl_config_knob da8xx_ddrctl_knobs[] = {
+ {
+ .name = "da850-pbbpr",
+ .reg = 0x20,
+ .mask = 0xffffff00,
+ .shift = 0,
+ },
+};
+
+struct da8xx_ddrctl_setting {
+ const char *name;
+ u32 val;
+};
+
+struct da8xx_ddrctl_board_settings {
+ const char *board;
+ const struct da8xx_ddrctl_setting *settings;
+};
+
+static const struct da8xx_ddrctl_setting da850_lcdk_ddrctl_settings[] = {
+ {
+ .name = "da850-pbbpr",
+ .val = 0x20,
+ },
+ { }
+};
+
+static const struct da8xx_ddrctl_board_settings da8xx_ddrctl_board_confs[] = {
+ {
+ .board = "ti,da850-lcdk",
+ .settings = da850_lcdk_ddrctl_settings,
+ },
+};
+
+static const struct da8xx_ddrctl_config_knob *
+da8xx_ddrctl_match_knob(const struct da8xx_ddrctl_setting *setting)
+{
+ const struct da8xx_ddrctl_config_knob *knob;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(da8xx_ddrctl_knobs); i++) {
+ knob = &da8xx_ddrctl_knobs[i];
+
+ if (strcmp(knob->name, setting->name) == 0)
+ return knob;
+ }
+
+ return NULL;
+}
+
+static const struct da8xx_ddrctl_setting *da8xx_ddrctl_get_board_settings(void)
+{
+ const struct da8xx_ddrctl_board_settings *board_settings;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(da8xx_ddrctl_board_confs); i++) {
+ board_settings = &da8xx_ddrctl_board_confs[i];
+
+ if (of_machine_is_compatible(board_settings->board))
+ return board_settings->settings;
+ }
+
+ return NULL;
+}
+
+static int da8xx_ddrctl_probe(struct platform_device *pdev)
+{
+ const struct da8xx_ddrctl_config_knob *knob;
+ const struct da8xx_ddrctl_setting *setting;
+ struct resource *res;
+ void __iomem *ddrctl;
+ struct device *dev;
+ u32 reg;
+
+ dev = &pdev->dev;
+
+ setting = da8xx_ddrctl_get_board_settings();
+ if (!setting) {
+ dev_err(dev, "no settings defined for this board\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ddrctl = devm_ioremap_resource(dev, res);
+ if (IS_ERR(ddrctl)) {
+ dev_err(dev, "unable to map memory controller registers\n");
+ return PTR_ERR(ddrctl);
+ }
+
+ for (; setting->name; setting++) {
+ knob = da8xx_ddrctl_match_knob(setting);
+ if (!knob) {
+ dev_warn(dev,
+ "no such config option: %s\n", setting->name);
+ continue;
+ }
+
+ if (knob->reg + sizeof(u32) > resource_size(res)) {
+ dev_warn(dev,
+ "register offset of '%s' exceeds mapped memory size\n",
+ knob->name);
+ continue;
+ }
+
+ reg = readl(ddrctl + knob->reg);
+ reg &= knob->mask;
+ reg |= setting->val << knob->shift;
+
+ dev_dbg(dev, "writing 0x%08x to %s\n", reg, setting->name);
+
+ writel(reg, ddrctl + knob->reg);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id da8xx_ddrctl_of_match[] = {
+ { .compatible = "ti,da850-ddr-controller", },
+ { },
+};
+
+static struct platform_driver da8xx_ddrctl_driver = {
+ .probe = da8xx_ddrctl_probe,
+ .driver = {
+ .name = "da850-ddr-controller",
+ .of_match_table = da8xx_ddrctl_of_match,
+ },
+};
+module_platform_driver(da8xx_ddrctl_driver);
+
+MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
+MODULE_DESCRIPTION("TI da8xx DDR2/mDDR controller driver");
+MODULE_LICENSE("GPL v2");