Merge changes from topic "arm_fpga_auto" into integration

* changes:
  feat(arm_fpga): write UART baud base clock frequency into DTB
  feat(arm_fpga): query PL011 to learn system frequency
  refactor(arm_fpga): move command line code into separate function
  fix(fdt): avoid output on missing DT property
  feat(arm_fpga): add ITS autodetection
  feat(arm_fpga): determine GICR base by probing
  feat(gicv3): introduce GIC component identification
  feat(libfdt): also allow changing base address
  fix(arm_fpga): avoid re-linking from executable ELF file

4 files changed, 275 insertions, 62 deletions

diff --git a/plat/arm/board/arm_fpga/build_axf.ld.S b/plat/arm/board/arm_fpga/build_axf.ld.S
index b4bc7d884..d8254e5b2 100644
--- a/plat/arm/board/arm_fpga/build_axf.ld.S
+++ b/plat/arm/board/arm_fpga/build_axf.ld.S
@@ -15,11 +15,11 @@
 OUTPUT_FORMAT("elf64-littleaarch64")
 OUTPUT_ARCH(aarch64)
 
-INPUT(./bl31/bl31.elf)
 INPUT(./rom_trampoline.o)
 INPUT(./kernel_trampoline.o)
 
 TARGET(binary)
+INPUT(./bl31.bin)
 INPUT(./fdts/arm_fpga.dtb)
 
 ENTRY(_start)
@@ -33,7 +33,7 @@ SECTIONS
 
 	.bl31 (BL31_BASE): {
 		ASSERT(. == ALIGN(PAGE_SIZE), "BL31_BASE is not page aligned");
-		*bl31.elf(.text* .data* .rodata* ro* .bss*)
+		*bl31.bin
 	}
 
 	.dtb (FPGA_PRELOADED_DTB_BASE): {
diff --git a/plat/arm/board/arm_fpga/fpga_bl31_setup.c b/plat/arm/board/arm_fpga/fpga_bl31_setup.c
index 2b5ca4af7..e1b3abb28 100644
--- a/plat/arm/board/arm_fpga/fpga_bl31_setup.c
+++ b/plat/arm/board/arm_fpga/fpga_bl31_setup.c
@@ -13,6 +13,7 @@
 #include <drivers/delay_timer.h>
 #include <drivers/generic_delay_timer.h>
 #include <lib/extensions/spe.h>
+#include <lib/mmio.h>
 #include <libfdt.h>
 
 #include "fpga_private.h"
@@ -20,6 +21,7 @@
 #include <platform_def.h>
 
 static entry_point_info_t bl33_image_ep_info;
+static unsigned int system_freq;
 volatile uint32_t secondary_core_spinlock;
 
 uintptr_t plat_get_ns_image_entrypoint(void)
@@ -118,18 +120,187 @@ entry_point_info_t *bl31_plat_get_next_image_ep_info(uint32_t type)
 	}
 }
 
-unsigned int plat_get_syscnt_freq2(void)
+/*
+ * Even though we sell the FPGA UART as an SBSA variant, it is actually
+ * a full fledged PL011. So the baudrate divider registers exist.
+ */
+#ifndef UARTIBRD
+#define UARTIBRD	0x024
+#define UARTFBRD	0x028
+#endif
+
+/* Round an integer to the closest multiple of a value. */
+static unsigned int round_multiple(unsigned int x, unsigned int multiple)
+{
+	if (multiple < 2) {
+		return x;
+	}
+
+	return ((x + (multiple / 2 - 1)) / multiple) * multiple;
+}
+
+#define PL011_FRAC_SHIFT	6
+#define FPGA_DEFAULT_BAUDRATE	38400
+#define PL011_OVERSAMPLING	16
+static unsigned int pl011_freq_from_divider(unsigned int divider)
+{
+	unsigned int freq;
+
+	freq = divider * FPGA_DEFAULT_BAUDRATE * PL011_OVERSAMPLING;
+
+	return freq >> PL011_FRAC_SHIFT;
+}
+
+/*
+ * The FPGAs run most peripherals from one main clock, among them the CPUs,
+ * the arch timer, and the UART baud base clock.
+ * The SCP knows this frequency and programs the UART clock divider for a
+ * 38400 bps baudrate. Recalculate the base input clock from there.
+ */
+static unsigned int fpga_get_system_frequency(void)
 {
 	const void *fdt = (void *)(uintptr_t)FPGA_PRELOADED_DTB_BASE;
-	int node;
+	int node, err;
 
+	/*
+	 * If the arch timer DT node has an explicit clock-frequency property
+	 * set, use that, to allow people overriding auto-detection.
+	 */
 	node = fdt_node_offset_by_compatible(fdt, 0, "arm,armv8-timer");
+	if (node >= 0) {
+		uint32_t freq;
+
+		err = fdt_read_uint32(fdt, node, "clock-frequency", &freq);
+		if (err >= 0) {
+			return freq;
+		}
+	}
+
+	node = fdt_node_offset_by_compatible(fdt, 0, "arm,pl011");
+	if (node >= 0) {
+		uintptr_t pl011_base;
+		unsigned int divider;
+
+		err = fdt_get_reg_props_by_index(fdt, node, 0,
+						 &pl011_base, NULL);
+		if (err >= 0) {
+			divider = mmio_read_32(pl011_base + UARTIBRD);
+			divider <<= PL011_FRAC_SHIFT;
+			divider += mmio_read_32(pl011_base + UARTFBRD);
+
+			/*
+			 * The result won't be exact, due to rounding errors,
+			 * but the input frequency was a multiple of 250 KHz.
+			 */
+			return round_multiple(pl011_freq_from_divider(divider),
+					      250000);
+		} else {
+			WARN("Cannot read PL011 MMIO base\n");
+		}
+	} else {
+		WARN("No PL011 DT node\n");
+	}
+
+	/* No PL011 DT node or calculation failed. */
+	return FPGA_DEFAULT_TIMER_FREQUENCY;
+}
+
+unsigned int plat_get_syscnt_freq2(void)
+{
+	if (system_freq == 0U) {
+		system_freq = fpga_get_system_frequency();
+	}
+
+	return system_freq;
+}
+
+static void fpga_dtb_update_clock(void *fdt, unsigned int freq)
+{
+	uint32_t freq_dtb = fdt32_to_cpu(freq);
+	uint32_t phandle;
+	int node, err;
+
+	node = fdt_node_offset_by_compatible(fdt, 0, "arm,pl011");
 	if (node < 0) {
-		return FPGA_DEFAULT_TIMER_FREQUENCY;
+		WARN("%s(): No PL011 DT node found\n", __func__);
+
+		return;
+	}
+
+	err = fdt_read_uint32(fdt, node, "clocks", &phandle);
+	if (err != 0) {
+		WARN("Cannot find clocks property\n");
+
+		return;
 	}
 
-	return fdt_read_uint32_default(fdt, node, "clock-frequency",
-				       FPGA_DEFAULT_TIMER_FREQUENCY);
+	node = fdt_node_offset_by_phandle(fdt, phandle);
+	if (node < 0) {
+		WARN("Cannot get phandle\n");
+
+		return;
+	}
+
+	err = fdt_setprop_inplace(fdt, node,
+				  "clock-frequency",
+				  &freq_dtb,
+				  sizeof(freq_dtb));
+	if (err < 0) {
+		WARN("Could not update DT baud clock frequency\n");
+
+		return;
+	}
+}
+
+#define CMDLINE_SIGNATURE	"CMD:"
+
+static int fpga_dtb_set_commandline(void *fdt, const char *cmdline)
+{
+	int chosen;
+	const char *eol;
+	char nul = 0;
+	int slen, err;
+
+	chosen = fdt_add_subnode(fdt, 0, "chosen");
+	if (chosen == -FDT_ERR_EXISTS) {
+		chosen = fdt_path_offset(fdt, "/chosen");
+	}
+
+	if (chosen < 0) {
+		return chosen;
+	}
+
+	/*
+	 * There is most likely an EOL at the end of the
+	 * command line, make sure we terminate the line there.
+	 * We can't replace the EOL with a NUL byte in the
+	 * source, as this is in read-only memory. So we first
+	 * create the property without any termination, then
+	 * append a single NUL byte.
+	 */
+	eol = strchr(cmdline, '\n');
+	if (eol == NULL) {
+		eol = strchr(cmdline, 0);
+	}
+	/* Skip the signature and omit the EOL/NUL byte. */
+	slen = eol - (cmdline + strlen(CMDLINE_SIGNATURE));
+	/*
+	 * Let's limit the size of the property, just in case
+	 * we find the signature by accident. The Linux kernel
+	 * limits to 4096 characters at most (in fact 2048 for
+	 * arm64), so that sounds like a reasonable number.
+	 */
+	if (slen > 4095) {
+		slen = 4095;
+	}
+
+	err = fdt_setprop(fdt, chosen, "bootargs",
+			  cmdline + strlen(CMDLINE_SIGNATURE), slen);
+	if (err != 0) {
+		return err;
+	}
+
+	return fdt_appendprop(fdt, chosen, "bootargs", &nul, 1);
 }
 
 static void fpga_prepare_dtb(void)
@@ -151,55 +322,13 @@ static void fpga_prepare_dtb(void)
 	}
 
 	/* Check for the command line signature. */
-	if (!strncmp(cmdline, "CMD:", 4)) {
-		int chosen;
-
-		INFO("using command line at 0x%x\n", FPGA_PRELOADED_CMD_LINE);
-
-		chosen = fdt_add_subnode(fdt, 0, "chosen");
-		if (chosen == -FDT_ERR_EXISTS) {
-			chosen = fdt_path_offset(fdt, "/chosen");
-		}
-		if (chosen < 0) {
-			ERROR("cannot find /chosen node: %d\n", chosen);
+	if (!strncmp(cmdline, CMDLINE_SIGNATURE, strlen(CMDLINE_SIGNATURE))) {
+		err = fpga_dtb_set_commandline(fdt, cmdline);
+		if (err == 0) {
+			INFO("using command line at 0x%x\n",
+			     FPGA_PRELOADED_CMD_LINE);
 		} else {
-			const char *eol;
-			char nul = 0;
-			int slen;
-
-			/*
-			 * There is most likely an EOL at the end of the
-			 * command line, make sure we terminate the line there.
-			 * We can't replace the EOL with a NUL byte in the
-			 * source, as this is in read-only memory. So we first
-			 * create the property without any termination, then
-			 * append a single NUL byte.
-			 */
-			eol = strchr(cmdline, '\n');
-			if (!eol) {
-				eol = strchr(cmdline, 0);
-			}
-			/* Skip the signature and omit the EOL/NUL byte. */
-			slen = eol - (cmdline + 4);
-
-			/*
-			 * Let's limit the size of the property, just in case
-			 * we find the signature by accident. The Linux kernel
-			 * limits to 4096 characters at most (in fact 2048 for
-			 * arm64), so that sounds like a reasonable number.
-			 */
-			if (slen > 4095) {
-				slen = 4095;
-			}
-			err = fdt_setprop(fdt, chosen, "bootargs",
-					  cmdline + 4, slen);
-			if (!err) {
-				err = fdt_appendprop(fdt, chosen, "bootargs",
-						     &nul, 1);
-			}
-			if (err) {
-				ERROR("Could not set command line: %d\n", err);
-			}
+			ERROR("failed to put command line into DTB: %d\n", err);
 		}
 	}
 
@@ -224,6 +353,7 @@ static void fpga_prepare_dtb(void)
 			INFO("Adjusting GICR DT region to cover %u cores\n",
 			      nr_cores);
 			err = fdt_adjust_gic_redist(fdt, nr_cores,
+						    fpga_get_redist_base(),
 						    fpga_get_redist_size());
 			if (err < 0) {
 				ERROR("Error %d fixing up GIC DT node\n", err);
@@ -231,6 +361,8 @@ static void fpga_prepare_dtb(void)
 		}
 	}
 
+	fpga_dtb_update_clock(fdt, system_freq);
+
 	/* Check whether we support the SPE PMU. Remove the DT node if not. */
 	if (!spe_supported()) {
 		int node = fdt_node_offset_by_compatible(fdt, 0,
@@ -241,6 +373,16 @@ static void fpga_prepare_dtb(void)
 		}
 	}
 
+	/* Check whether we have an ITS. Remove the DT node if not. */
+	if (!fpga_has_its()) {
+		int node = fdt_node_offset_by_compatible(fdt, 0,
+							 "arm,gic-v3-its");
+
+		if (node >= 0) {
+			fdt_del_node(fdt, node);
+		}
+	}
+
 	err = fdt_pack(fdt);
 	if (err < 0) {
 		ERROR("Failed to pack Device Tree at %p: error %d\n", fdt, err);
diff --git a/plat/arm/board/arm_fpga/fpga_gicv3.c b/plat/arm/board/arm_fpga/fpga_gicv3.c
index 4a97beb96..e06a9da56 100644
--- a/plat/arm/board/arm_fpga/fpga_gicv3.c
+++ b/plat/arm/board/arm_fpga/fpga_gicv3.c
@@ -1,13 +1,14 @@
 /*
- * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020-2021, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
 #include <common/debug.h>
 #include <common/fdt_wrappers.h>
-#include <drivers/arm/gicv3.h>
+#include <drivers/arm/arm_gicv3_common.h>
 #include <drivers/arm/gic_common.h>
+#include <drivers/arm/gicv3.h>
 #include <lib/mmio.h>
 #include <libfdt.h>
 
@@ -21,6 +22,7 @@ static const interrupt_prop_t fpga_interrupt_props[] = {
 };
 
 static uintptr_t fpga_rdistif_base_addrs[PLATFORM_CORE_COUNT];
+static int nr_itses;
 
 static unsigned int fpga_mpidr_to_core_pos(unsigned long mpidr)
 {
@@ -38,6 +40,8 @@ static gicv3_driver_data_t fpga_gicv3_driver_data = {
 void plat_fpga_gic_init(void)
 {
 	const void *fdt = (void *)(uintptr_t)FPGA_PRELOADED_DTB_BASE;
+	uintptr_t gicr_base = 0U;
+	uint32_t iidr;
 	int node, ret;
 
 	node = fdt_node_offset_by_compatible(fdt, 0, "arm,gic-v3");
@@ -54,11 +58,66 @@ void plat_fpga_gic_init(void)
 		return;
 	}
 
-	ret = fdt_get_reg_props_by_index(fdt, node, 1,
-				 &fpga_gicv3_driver_data.gicr_base, NULL);
-	if (ret < 0) {
-		WARN("Could not read GIC redistributor address from DT.\n");
-		return;
+	iidr = mmio_read_32(fpga_gicv3_driver_data.gicd_base + GICD_IIDR);
+	if (((iidr & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_600) ||
+	    ((iidr & IIDR_MODEL_MASK) == IIDR_MODEL_ARM_GIC_700)) {
+		unsigned int frame_id;
+
+		/*
+		 * According to the GIC TRMs, if there are any ITSes, they
+		 * start four 64K pages after the distributor. After all
+		 * the ITSes then follow the redistributors.
+		 */
+		gicr_base = fpga_gicv3_driver_data.gicd_base + (4U << 16);
+
+		do {
+			uint64_t its_typer;
+
+			/* Each GIC component can be identified by its ID. */
+			frame_id = gicv3_get_component_partnum(gicr_base);
+
+			if (frame_id == PIDR_COMPONENT_ARM_REDIST) {
+				INFO("Found %d ITSes, redistributors start at 0x%llx\n",
+				     nr_itses, (unsigned long long)gicr_base);
+				break;
+			}
+
+			if (frame_id != PIDR_COMPONENT_ARM_ITS) {
+				WARN("GICv3: found unexpected frame 0x%x\n",
+					frame_id);
+				gicr_base = 0U;
+				break;
+			}
+
+			/*
+			 * Found an ITS, now work out if it supports virtual
+			 * SGIs (for direct guest injection). If yes, each
+			 * ITS occupies four 64K pages, otherwise just two.
+			 */
+			its_typer = mmio_read_64(gicr_base + GITS_TYPER);
+			if ((its_typer & GITS_TYPER_VSGI) != 0U) {
+				gicr_base += 4U << 16;
+			} else {
+				gicr_base += 2U << 16;
+			}
+			nr_itses++;
+		} while (true);
+	}
+
+	/*
+	 * If this is not a GIC-600 or -700, or the autodetection above failed,
+	 * use the base address from the device tree.
+	 */
+	if (gicr_base == 0U) {
+		ret = fdt_get_reg_props_by_index(fdt, node, 1,
+					&fpga_gicv3_driver_data.gicr_base,
+					NULL);
+		if (ret < 0) {
+			WARN("Could not read GIC redistributor address from DT.\n");
+			return;
+		}
+	} else {
+		fpga_gicv3_driver_data.gicr_base = gicr_base;
 	}
 
 	gicv3_driver_init(&fpga_gicv3_driver_data);
@@ -91,3 +150,13 @@ uintptr_t fpga_get_redist_size(void)
 
 	return gicv3_redist_size(typer_val);
 }
+
+uintptr_t fpga_get_redist_base(void)
+{
+	return fpga_gicv3_driver_data.gicr_base;
+}
+
+bool fpga_has_its(void)
+{
+	return nr_itses > 0;
+}
diff --git a/plat/arm/board/arm_fpga/fpga_private.h b/plat/arm/board/arm_fpga/fpga_private.h
index cc809c4e4..84d651cea 100644
--- a/plat/arm/board/arm_fpga/fpga_private.h
+++ b/plat/arm/board/arm_fpga/fpga_private.h
@@ -26,6 +26,8 @@ void fpga_pwr_gic_off(void);
 unsigned int plat_fpga_calc_core_pos(uint32_t mpid);
 unsigned int fpga_get_nr_gic_cores(void);
 uintptr_t fpga_get_redist_size(void);
+uintptr_t fpga_get_redist_base(void);
+bool fpga_has_its(void);
 
 #endif /* __ASSEMBLER__ */