stm32mp1: Add DDR support and its security with TZC400

The DDR driver is under dual license, BSD and GPLv2.
The configuration parameters are taken from device tree.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Nicolas Le Bayon <nicolas.le.bayon@st.com>
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
diff --git a/drivers/st/ddr/stm32mp1_ram.c b/drivers/st/ddr/stm32mp1_ram.c
new file mode 100644
index 0000000..6d515ec
--- /dev/null
+++ b/drivers/st/ddr/stm32mp1_ram.c
@@ -0,0 +1,308 @@
+/*
+ * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+ */
+
+#include <arch_helpers.h>
+#include <boot_api.h>
+#include <debug.h>
+#include <dt-bindings/clock/stm32mp1-clks.h>
+#include <errno.h>
+#include <libfdt.h>
+#include <mmio.h>
+#include <platform_def.h>
+#include <stm32mp1_clk.h>
+#include <stm32mp1_ddr.h>
+#include <stm32mp1_ddr_helpers.h>
+#include <stm32mp1_dt.h>
+#include <stm32mp1_private.h>
+#include <stm32mp1_ram.h>
+#include <stm32mp1_rcc.h>
+
+#define DDR_PATTERN	0xAAAAAAAAU
+#define DDR_ANTIPATTERN	0x55555555U
+
+static struct ddr_info ddr_priv_data;
+
+int stm32mp1_ddr_clk_enable(struct ddr_info *priv, uint16_t mem_speed)
+{
+	unsigned long ddrphy_clk, ddr_clk, mem_speed_hz;
+
+	ddr_enable_clock();
+
+	ddrphy_clk = stm32mp1_clk_get_rate(DDRPHYC);
+
+	VERBOSE("DDR: mem_speed (%d MHz), RCC %ld MHz\n",
+		mem_speed, ddrphy_clk / 1000U / 1000U);
+
+	mem_speed_hz = (uint32_t)mem_speed * 1000U * 1000U;
+
+	/* Max 10% frequency delta */
+	if (ddrphy_clk > mem_speed_hz) {
+		ddr_clk = ddrphy_clk - mem_speed_hz;
+	} else {
+		ddr_clk = mem_speed_hz - ddrphy_clk;
+	}
+	if (ddr_clk > mem_speed_hz) {
+		ERROR("DDR expected freq %d MHz, current is %ld MHz\n",
+		      mem_speed, ddrphy_clk / 1000U / 1000U);
+		return -1;
+	}
+	return 0;
+}
+
+/*******************************************************************************
+ * This function tests the DDR data bus wiring.
+ * This is inspired from the Data Bus Test algorithm written by Michael Barr
+ * in "Programming Embedded Systems in C and C++" book.
+ * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
+ * File: memtest.c - This source code belongs to Public Domain.
+ * Returns 0 if success, and address value else.
+ ******************************************************************************/
+static uint32_t ddr_test_data_bus(void)
+{
+	uint32_t pattern;
+
+	for (pattern = 1U; pattern != 0U; pattern <<= 1) {
+		mmio_write_32(STM32MP1_DDR_BASE, pattern);
+
+		if (mmio_read_32(STM32MP1_DDR_BASE) != pattern) {
+			return (uint32_t)STM32MP1_DDR_BASE;
+		}
+	}
+
+	return 0;
+}
+
+/*******************************************************************************
+ * This function tests the DDR address bus wiring.
+ * This is inspired from the Data Bus Test algorithm written by Michael Barr
+ * in "Programming Embedded Systems in C and C++" book.
+ * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
+ * File: memtest.c - This source code belongs to Public Domain.
+ * Returns 0 if success, and address value else.
+ ******************************************************************************/
+static uint32_t ddr_test_addr_bus(void)
+{
+	uint64_t addressmask = (ddr_priv_data.info.size - 1U);
+	uint64_t offset;
+	uint64_t testoffset = 0;
+
+	/* Write the default pattern at each of the power-of-two offsets. */
+	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
+	     offset <<= 1) {
+		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)offset,
+			      DDR_PATTERN);
+	}
+
+	/* Check for address bits stuck high. */
+	mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
+		      DDR_ANTIPATTERN);
+
+	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
+	     offset <<= 1) {
+		if (mmio_read_32(STM32MP1_DDR_BASE + (uint32_t)offset) !=
+		    DDR_PATTERN) {
+			return (uint32_t)(STM32MP1_DDR_BASE + offset);
+		}
+	}
+
+	mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN);
+
+	/* Check for address bits stuck low or shorted. */
+	for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U;
+	     testoffset <<= 1) {
+		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
+			      DDR_ANTIPATTERN);
+
+		if (mmio_read_32(STM32MP1_DDR_BASE) != DDR_PATTERN) {
+			return STM32MP1_DDR_BASE;
+		}
+
+		for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
+		     offset <<= 1) {
+			if ((mmio_read_32(STM32MP1_DDR_BASE +
+					  (uint32_t)offset) != DDR_PATTERN) &&
+			    (offset != testoffset)) {
+				return (uint32_t)(STM32MP1_DDR_BASE + offset);
+			}
+		}
+
+		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
+			      DDR_PATTERN);
+	}
+
+	return 0;
+}
+
+/*******************************************************************************
+ * This function checks the DDR size. It has to be run with Data Cache off.
+ * This test is run before data have been put in DDR, and is only done for
+ * cold boot. The DDR data can then be overwritten, and it is not useful to
+ * restore its content.
+ * Returns DDR computed size.
+ ******************************************************************************/
+static uint32_t ddr_check_size(void)
+{
+	uint32_t offset = sizeof(uint32_t);
+
+	mmio_write_32(STM32MP1_DDR_BASE, DDR_PATTERN);
+
+	while (offset < STM32MP1_DDR_MAX_SIZE) {
+		mmio_write_32(STM32MP1_DDR_BASE + offset, DDR_ANTIPATTERN);
+		dsb();
+
+		if (mmio_read_32(STM32MP1_DDR_BASE) != DDR_PATTERN) {
+			break;
+		}
+
+		offset <<= 1;
+	}
+
+	INFO("Memory size = 0x%x (%d MB)\n", offset, offset / (1024U * 1024U));
+
+	return offset;
+}
+
+static int stm32mp1_ddr_setup(void)
+{
+	struct ddr_info *priv = &ddr_priv_data;
+	int ret;
+	struct stm32mp1_ddr_config config;
+	int node, len;
+	uint32_t tamp_clk_off = 0, uret, idx;
+	void *fdt;
+
+#define PARAM(x, y)							\
+	{								\
+		.name = x,						\
+		.offset = offsetof(struct stm32mp1_ddr_config, y),	\
+		.size = sizeof(config.y) / sizeof(uint32_t)		\
+	}
+
+#define CTL_PARAM(x) PARAM("st,ctl-"#x, c_##x)
+#define PHY_PARAM(x) PARAM("st,phy-"#x, p_##x)
+
+	const struct {
+		const char *name; /* Name in DT */
+		const uint32_t offset; /* Offset in config struct */
+		const uint32_t size;   /* Size of parameters */
+	} param[] = {
+		CTL_PARAM(reg),
+		CTL_PARAM(timing),
+		CTL_PARAM(map),
+		CTL_PARAM(perf),
+		PHY_PARAM(reg),
+		PHY_PARAM(timing),
+		PHY_PARAM(cal)
+	};
+
+	if (fdt_get_address(&fdt) == 0) {
+		return -ENOENT;
+	}
+
+	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
+	if (node < 0) {
+		ERROR("%s: Cannot read DDR node in DT\n", __func__);
+		return -EINVAL;
+	}
+
+	config.info.speed =
+		(uint16_t)fdt_read_uint32_default(node, "st,mem-speed",
+						  STM32MP1_DDR_SPEED_DFLT);
+	config.info.size = fdt_read_uint32_default(node, "st,mem-size",
+						   STM32MP1_DDR_SIZE_DFLT);
+	config.info.name = fdt_getprop(fdt, node, "st,mem-name", &len);
+	if (config.info.name == NULL) {
+		VERBOSE("%s: no st,mem-name\n", __func__);
+		return -EINVAL;
+	}
+	INFO("RAM: %s\n", config.info.name);
+
+	for (idx = 0; idx < ARRAY_SIZE(param); idx++) {
+		ret = fdt_read_uint32_array(node, param[idx].name,
+					    (void *)((uint32_t)&config +
+						     param[idx].offset),
+					    param[idx].size);
+
+		VERBOSE("%s: %s[0x%x] = %d\n", __func__,
+			param[idx].name, param[idx].size, ret);
+		if (ret != 0) {
+			ERROR("%s: Cannot read %s\n",
+			      __func__, param[idx].name);
+			return -EINVAL;
+		}
+	}
+
+	if (!stm32mp1_clk_is_enabled(RTCAPB)) {
+		tamp_clk_off = 1;
+		if (stm32mp1_clk_enable(RTCAPB) != 0) {
+			return -EINVAL;
+		}
+	}
+
+	if (tamp_clk_off != 0U) {
+		if (stm32mp1_clk_disable(RTCAPB) != 0) {
+			return -EINVAL;
+		}
+	}
+
+	/* Disable axidcg clock gating during init */
+	mmio_clrbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
+
+	stm32mp1_ddr_init(priv, &config);
+
+	/* Enable axidcg clock gating */
+	mmio_setbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
+
+	priv->info.size = config.info.size;
+
+	VERBOSE("%s : ram size(%x, %x)\n", __func__,
+		(uint32_t)priv->info.base, (uint32_t)priv->info.size);
+
+	dcsw_op_all(DC_OP_CISW);
+	write_sctlr(read_sctlr() & ~SCTLR_C_BIT);
+
+	uret = ddr_test_data_bus();
+	if (uret != 0U) {
+		ERROR("DDR data bus test: can't access memory @ 0x%x\n",
+		      uret);
+		panic();
+	}
+
+	uret = ddr_test_addr_bus();
+	if (uret != 0U) {
+		ERROR("DDR addr bus test: can't access memory @ 0x%x\n",
+		      uret);
+		panic();
+	}
+
+	uret = ddr_check_size();
+	if (uret < config.info.size) {
+		ERROR("DDR size: 0x%x does not match DT config: 0x%x\n",
+		      uret, config.info.size);
+		panic();
+	}
+
+	write_sctlr(read_sctlr() | SCTLR_C_BIT);
+
+	return 0;
+}
+
+int stm32mp1_ddr_probe(void)
+{
+	struct ddr_info *priv = &ddr_priv_data;
+
+	VERBOSE("STM32MP DDR probe\n");
+
+	priv->ctl = (struct stm32mp1_ddrctl *)DDRCTRL_BASE;
+	priv->phy = (struct stm32mp1_ddrphy *)DDRPHYC_BASE;
+	priv->pwr = PWR_BASE;
+	priv->rcc = RCC_BASE;
+
+	priv->info.base = STM32MP1_DDR_BASE;
+	priv->info.size = 0;
+
+	return stm32mp1_ddr_setup();
+}