feat(st-ddr): add STM32MP2 driver

Add driver to support DDR on STM32MP2 platform. It drives the DDR PHY
and its firmware, as well as the DDR controller.

Signed-off-by: Nicolas Le Bayon <nicolas.le.bayon@st.com>
Signed-off-by: Maxime Méré <maxime.mere@foss.st.com>
Change-Id: I93de2db1b9378d5654e76b3bf6f3407d80bc4ca5
diff --git a/drivers/st/ddr/stm32mp2_ram.c b/drivers/st/ddr/stm32mp2_ram.c
new file mode 100644
index 0000000..95f05e7
--- /dev/null
+++ b/drivers/st/ddr/stm32mp2_ram.c
@@ -0,0 +1,210 @@
+/*
+ * Copyright (C) 2021-2024, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+ */
+
+#include <errno.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <common/fdt_wrappers.h>
+#include <drivers/clk.h>
+#include <drivers/st/stm32mp2_ddr.h>
+#include <drivers/st/stm32mp2_ddr_helpers.h>
+#include <drivers/st/stm32mp2_ram.h>
+#include <drivers/st/stm32mp_ddr.h>
+#include <drivers/st/stm32mp_ddr_test.h>
+#include <drivers/st/stm32mp_ram.h>
+
+#include <lib/mmio.h>
+#include <libfdt.h>
+
+#include <platform_def.h>
+
+static struct stm32mp_ddr_priv ddr_priv_data;
+static bool ddr_self_refresh;
+
+static int ddr_dt_get_ui_param(void *fdt, int node, struct stm32mp_ddr_config *config)
+{
+	int ret;
+	uint32_t size;
+
+	size = sizeof(struct user_input_basic) / sizeof(int);
+	ret = fdt_read_uint32_array(fdt, node, "st,phy-basic", size, (uint32_t *)&config->uib);
+
+	VERBOSE("%s: %s[0x%x] = %d\n", __func__, "st,phy-basic", size, ret);
+	if (ret != 0) {
+		ERROR("%s: can't read %s, error=%d\n", __func__, "st,phy-basic", ret);
+		return -EINVAL;
+	}
+
+	size = sizeof(struct user_input_advanced) / sizeof(int);
+	ret = fdt_read_uint32_array(fdt, node, "st,phy-advanced", size, (uint32_t *)&config->uia);
+
+	VERBOSE("%s: %s[0x%x] = %d\n", __func__, "st,phy-advanced", size, ret);
+	if (ret != 0) {
+		ERROR("%s: can't read %s, error=%d\n", __func__, "st,phy-advanced", ret);
+		return -EINVAL;
+	}
+
+	size = sizeof(struct user_input_mode_register) / sizeof(int);
+	ret = fdt_read_uint32_array(fdt, node, "st,phy-mr", size, (uint32_t *)&config->uim);
+
+	VERBOSE("%s: %s[0x%x] = %d\n", __func__, "st,phy-mr", size, ret);
+	if (ret != 0) {
+		ERROR("%s: can't read %s, error=%d\n", __func__, "st,phy-mr", ret);
+		return -EINVAL;
+	}
+
+	size = sizeof(struct user_input_swizzle) / sizeof(int);
+	ret = fdt_read_uint32_array(fdt, node, "st,phy-swizzle", size, (uint32_t *)&config->uis);
+
+	VERBOSE("%s: %s[0x%x] = %d\n", __func__, "st,phy-swizzle", size, ret);
+	if (ret != 0) {
+		ERROR("%s: can't read %s, error=%d\n", __func__, "st,phy-swizzle", ret);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int stm32mp2_ddr_setup(void)
+{
+	struct stm32mp_ddr_priv *priv = &ddr_priv_data;
+	int ret;
+	struct stm32mp_ddr_config config;
+	int node;
+	uintptr_t uret;
+	void *fdt;
+
+	const struct stm32mp_ddr_param param[] = {
+		CTL_PARAM(reg),
+		CTL_PARAM(timing),
+		CTL_PARAM(map),
+		CTL_PARAM(perf)
+	};
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -ENOENT;
+	}
+
+	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
+	if (node < 0) {
+		ERROR("%s: can't read DDR node in DT\n", __func__);
+		return -EINVAL;
+	}
+
+	ret = stm32mp_ddr_dt_get_info(fdt, node, &config.info);
+	if (ret < 0) {
+		return ret;
+	}
+
+	ret = stm32mp_ddr_dt_get_param(fdt, node, param, ARRAY_SIZE(param), (uintptr_t)&config);
+	if (ret < 0) {
+		return ret;
+	}
+
+	ret = ddr_dt_get_ui_param(fdt, node, &config);
+	if (ret < 0) {
+		return ret;
+	}
+
+	config.self_refresh = false;
+
+	if (stm32mp_is_wakeup_from_standby()) {
+		config.self_refresh = true;
+	}
+
+	/*  Map dynamically RETRAM area to save or restore PHY retention registers */
+	if (stm32mp_map_retram() != 0) {
+		panic();
+	}
+
+	stm32mp2_ddr_init(priv, &config);
+
+	/*  Unmap RETRAM, no more used until next DDR initialization call */
+	if (stm32mp_unmap_retram() != 0) {
+		panic();
+	}
+
+	priv->info.size = config.info.size;
+
+	VERBOSE("%s : ram size(%lx, %lx)\n", __func__, priv->info.base, priv->info.size);
+
+	if (stm32mp_map_ddr_non_cacheable() != 0) {
+		panic();
+	}
+
+	if (config.self_refresh) {
+		uret = stm32mp_ddr_test_rw_access();
+		if (uret != 0UL) {
+			ERROR("DDR rw test: can't access memory @ 0x%lx\n", uret);
+			panic();
+		}
+
+		/* TODO Restore area overwritten by training */
+		//stm32_restore_ddr_training_area();
+	} else {
+		size_t retsize;
+
+		uret = stm32mp_ddr_test_data_bus();
+		if (uret != 0UL) {
+			ERROR("DDR data bus test: can't access memory @ 0x%lx\n", uret);
+			panic();
+		}
+
+		uret = stm32mp_ddr_test_addr_bus(config.info.size);
+		if (uret != 0UL) {
+			ERROR("DDR addr bus test: can't access memory @ 0x%lx\n", uret);
+			panic();
+		}
+
+		retsize = stm32mp_ddr_check_size();
+		if (retsize < config.info.size) {
+			ERROR("DDR size: 0x%zx does not match DT config: 0x%zx\n",
+			      retsize, config.info.size);
+			panic();
+		}
+
+		INFO("Memory size = 0x%zx (%zu MB)\n", retsize, retsize / (1024U * 1024U));
+	}
+
+	/*
+	 * Initialization sequence has configured DDR registers with settings.
+	 * The Self Refresh (SR) mode corresponding to these settings has now
+	 * to be set.
+	 */
+	ddr_set_sr_mode(ddr_read_sr_mode());
+
+	if (stm32mp_unmap_ddr() != 0) {
+		panic();
+	}
+
+	/* Save DDR self_refresh state */
+	ddr_self_refresh = config.self_refresh;
+
+	return 0;
+}
+
+bool stm32mp2_ddr_is_restored(void)
+{
+	return ddr_self_refresh;
+}
+
+int stm32mp2_ddr_probe(void)
+{
+	struct stm32mp_ddr_priv *priv = &ddr_priv_data;
+
+	VERBOSE("STM32MP DDR probe\n");
+
+	priv->ctl = (struct stm32mp_ddrctl *)stm32mp_ddrctrl_base();
+	priv->phy = (struct stm32mp_ddrphy *)stm32mp_ddrphyc_base();
+	priv->pwr = stm32mp_pwr_base();
+	priv->rcc = stm32mp_rcc_base();
+
+	priv->info.base = STM32MP_DDR_BASE;
+	priv->info.size = 0;
+
+	return stm32mp2_ddr_setup();
+}