[U-Boot] [RFC v2 2/2] arm64: zynqmp: spl: install a PMU firmware config object at runtime
Luca Ceresoli
luca at lucaceresoli.net
Thu Mar 21 15:48:57 UTC 2019
Optionally allow U-Boot to load at the PMU firmware configuration object
into the Power Management Unit (PMU) on Xilinx ZynqMP.
The configuration object is required by the PMU FW to enable most SoC
peripherals. So far the only way to boot using U-Boot SPL was to hard-code
the configuration object in the PMU firmware. Allow a different boot
process, where the PMU FW is equal for any ZynqMP chip and its
configuration is passed at runtime by U-Boot SPL.
All the code for Inter-processor communication with the PMU is isolated in
a new file (pmu_ipc.c). The code is inspired by the same feature as
implemented in the Xilinx First Stage Bootloader (FSBL) and Arm Trusted
Firmware:
* https://github.com/Xilinx/embeddedsw/blob/fb647e6b4c00f5154eba52a88b948195b6f1dc2b/lib/sw_apps/zynqmp_fsbl/src/xfsbl_misc_drivers.c#L295
* https://github.com/ARM-software/arm-trusted-firmware/blob/c48d02bade88b07fa7f43aa44e5217f68e5d047f/plat/xilinx/zynqmp/pm_service/pm_api_sys.c#L357
The load is logged on the console during boot:
U-Boot SPL 2018.01 (Mar 20 2019 - 08:12:21)
Loading PMUFW cfg obj (2008 bytes)
EL Level: EL3
...
Signed-off-by: Luca Ceresoli <luca at lucaceresoli.net>
---
Changes RFC v1 -> RFC v2:
- Load the cfg_obj in SPL, not U-Boot proper: this required a complete
reimplementation since we cannot rely on ATF now
- Update and refine the Kconfig option help
Todo:
- don't compile pm_cfg_obj.c from source, load it from a binary file
---
board/xilinx/zynqmp/Kconfig | 26 ++++++++
board/xilinx/zynqmp/Makefile | 5 ++
board/xilinx/zynqmp/pmu_ipc.c | 116 ++++++++++++++++++++++++++++++++++
board/xilinx/zynqmp/pmu_ipc.h | 14 ++++
board/xilinx/zynqmp/zynqmp.c | 11 ++++
5 files changed, 172 insertions(+)
create mode 100644 board/xilinx/zynqmp/pmu_ipc.c
create mode 100644 board/xilinx/zynqmp/pmu_ipc.h
diff --git a/board/xilinx/zynqmp/Kconfig b/board/xilinx/zynqmp/Kconfig
index 7d1f7398c3e9..4201e38571e7 100644
--- a/board/xilinx/zynqmp/Kconfig
+++ b/board/xilinx/zynqmp/Kconfig
@@ -15,4 +15,30 @@ config CMD_ZYNQMP
and authentication feature enabled while generating
BOOT.BIN using Xilinx bootgen tool.
+config ZYNQMP_LOAD_PM_CFG_OBJ_FILE
+ string "PMU firmware configuration object to load at runtime"
+ help
+ Path to a PMU firmware configuration object to be built into
+ U-Boot and loaded at runtime by SPL into the PMU firmware.
+
+ The ZynqMP Power Management Unit (PMU) needs a configuration
+ object for most SoC peripherals to work. It can be either
+ hard-coded in the PMUFW or passed at runtime.
+
+ If the configuration object is not hard-coded in the PMU
+ firmware, U-Boot SPL can load it at runtime. To enable this
+ feature set here the file name (absolute path or relative to
+ board/xilinx/zynqmp/). It will be loaded into the PMU firmware by
+ U-Boot SPL during board initialization.
+
+ Note: if your pm_cfg_obj.c is generated by the Xilinx tools,
+ you must remove any linking directives from the
+ XPm_ConfigObject declaration! E.g.:
+
+ -const u32 XPm_ConfigObject[] __attribute__((used, section(".sys_cfg_data"))) = {
+ +const u32 XPm_ConfigObject[] = {
+
+ Leave this option empty if your PMU firmware has a hard-coded
+ configuration object or you are loading it by any other means.
+
endif
diff --git a/board/xilinx/zynqmp/Makefile b/board/xilinx/zynqmp/Makefile
index 80f8ca7e1e4b..0d8f52ecd631 100644
--- a/board/xilinx/zynqmp/Makefile
+++ b/board/xilinx/zynqmp/Makefile
@@ -33,6 +33,11 @@ ifneq ($(call ifdef_any_of, CONFIG_ZYNQMP_PSU_INIT_ENABLED CONFIG_SPL_BUILD),)
obj-y += $(init-objs)
endif
+ifneq ($(CONFIG_ZYNQMP_LOAD_PM_CFG_OBJ_FILE),"")
+CFLAGS_zynqmp.o += -DZYNQMP_LOAD_PM_CFG_OBJ -I$(srctree)/$(src)
+obj-$(CONFIG_SPL_BUILD) += pmu_ipc.o
+endif
+
obj-$(CONFIG_MMC_SDHCI_ZYNQ) += tap_delays.o
ifndef CONFIG_SPL_BUILD
diff --git a/board/xilinx/zynqmp/pmu_ipc.c b/board/xilinx/zynqmp/pmu_ipc.c
new file mode 100644
index 000000000000..6306d33d6f17
--- /dev/null
+++ b/board/xilinx/zynqmp/pmu_ipc.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Inter-Processor Communication with the Platform Management Unit (PMU)
+ * firmware.
+ *
+ * (C) Copyright 2019 Luca Ceresoli
+ * Luca Ceresoli <luca at lucaceresoli.net>
+ */
+
+#include "pmu_ipc.h"
+#include <common.h>
+#include <asm/io.h>
+
+/* IPI bitmasks, register base and register offsets */
+#define IPI_BIT_MASK_APU 0x00001
+#define IPI_BIT_MASK_PMU0 0x10000
+#define IPI_REG_BASE_APU 0xFF300000
+#define IPI_REG_BASE_PMU0 0xFF330000
+#define IPI_REG_OFFSET_TRIG 0x00
+#define IPI_REG_OFFSET_OBR 0x04
+
+/* IPI mailbox buffer offsets */
+#define IPI_BUF_BASE_APU 0xFF990400
+#define IPI_BUF_OFFSET_TARGET_PMU 0x1C0
+#define IPI_BUF_OFFSET_REQ 0x00
+#define IPI_BUF_OFFSET_RESP 0x20
+
+/* Xilinx FSBL sets 8, ATF sets 6. Which one is correct? */
+#define PMUFW_PAYLOAD_ARG_CNT 6
+
+/* PMUFW commands */
+#define PMUFW_CMD_SET_CONFIGURATION 2
+
+static void pmu_ipc_send_request(const u32 *req, size_t req_len)
+{
+ u32 *mbx = IPI_BUF_BASE_APU +
+ IPI_BUF_OFFSET_TARGET_PMU +
+ IPI_BUF_OFFSET_REQ;
+ size_t i;
+
+ for (i = 0; i < req_len; i++)
+ writel(req[i], &mbx[i]);
+}
+
+static void pmu_ipc_read_response(unsigned int *value, size_t count)
+{
+ u32 *mbx = IPI_BUF_BASE_APU +
+ IPI_BUF_OFFSET_TARGET_PMU +
+ IPI_BUF_OFFSET_RESP;
+ size_t i;
+
+ for (i = 0; i < count; i++)
+ value[i] = readl(&mbx[i]);
+}
+
+/**
+ * Send request to PMU and get the response.
+ *
+ * @req Request buffer. Byte 0 is the API ID, other bytes are optional
+ * parameters.
+ * @req_len Request length in number of 32-bit words.
+ * @res Response buffer. Byte 0 is the error code, other bytes are
+ * optional parameters. Optional, if @res_maxlen==0 the parameters
+ * will not be read.
+ * @res_maxlen Space allocated for the response in number of 32-bit words.
+ *
+ * @return Error code returned by the PMU (i.e. the first word of the response)
+ */
+static int pmu_ipc_request(const u32 *req, size_t req_len,
+ u32 *res, size_t res_maxlen)
+{
+ u32 status;
+
+ if (req_len > PMUFW_PAYLOAD_ARG_CNT ||
+ res_maxlen > PMUFW_PAYLOAD_ARG_CNT)
+ return -EINVAL;
+
+ pmu_ipc_send_request(req, req_len);
+
+ /* Raise Inter-Processor Interrupt to PMU and wait for response */
+ writel(IPI_BIT_MASK_PMU0, IPI_REG_BASE_APU + IPI_REG_OFFSET_TRIG);
+ do {
+ status = readl(IPI_REG_BASE_APU + IPI_REG_OFFSET_OBR);
+ } while (status & IPI_BIT_MASK_PMU0);
+
+ pmu_ipc_read_response(res, res_maxlen);
+
+ return 0;
+}
+
+/**
+ * Send a configuration object to the PMU firmware.
+ *
+ * @cfg_obj Pointer to the configuration object
+ * @size Size of @cfg_obj in bytes
+ */
+void zynqmp_pmufw_load_config_object(const void *cfg_obj, size_t size)
+{
+ const u32 *ocm = (u32 *)CONFIG_SPL_TEXT_BASE;
+ const u32 request[] = {
+ PMUFW_CMD_SET_CONFIGURATION,
+ CONFIG_SPL_TEXT_BASE
+ };
+ u32 response;
+ int err;
+
+ printf("Loading PMUFW cfg obj (%ld bytes)\n", size);
+
+ memcpy(ocm, cfg_obj, size);
+
+ err = pmu_ipc_request(request, ARRAY_SIZE(request), &response, 1);
+ if (err)
+ panic("Cannot load PMUFW configuration object (%d)\n", err);
+ if (response != 0)
+ panic("PMUFW returned 0x%08x status!\n", response);
+}
diff --git a/board/xilinx/zynqmp/pmu_ipc.h b/board/xilinx/zynqmp/pmu_ipc.h
new file mode 100644
index 000000000000..37bb72c1b20a
--- /dev/null
+++ b/board/xilinx/zynqmp/pmu_ipc.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2019 Luca Ceresoli
+ * Luca Ceresoli <luca at lucaceresoli.net>
+ */
+
+#ifndef __ZYNQMP_PMU_IPC_H__
+#define __ZYNQMP_PMU_IPC_H__
+
+#include <linux/types.h>
+
+void zynqmp_pmufw_load_config_object(const void *cfg_obj, size_t size);
+
+#endif /* __ZYNQMP_PMU_IPC_H__ */
diff --git a/board/xilinx/zynqmp/zynqmp.c b/board/xilinx/zynqmp/zynqmp.c
index 5e1d2116bc32..1d5e25961863 100644
--- a/board/xilinx/zynqmp/zynqmp.c
+++ b/board/xilinx/zynqmp/zynqmp.c
@@ -4,6 +4,8 @@
* Michal Simek <michal.simek at xilinx.com>
*/
+#include "pmu_ipc.h"
+
#include <common.h>
#include <sata.h>
#include <ahci.h>
@@ -302,6 +304,10 @@ static char *zynqmp_get_silicon_idcode_name(void)
}
#endif
+#ifdef ZYNQMP_LOAD_PM_CFG_OBJ
+#include CONFIG_ZYNQMP_LOAD_PM_CFG_OBJ_FILE
+#endif
+
int board_early_init_f(void)
{
int ret = 0;
@@ -332,6 +338,11 @@ int board_early_init_f(void)
int board_init(void)
{
+#if defined(CONFIG_SPL_BUILD) && defined(ZYNQMP_LOAD_PM_CFG_OBJ)
+ zynqmp_pmufw_load_config_object(XPm_ConfigObject,
+ sizeof(XPm_ConfigObject));
+#endif
+
printf("EL Level:\tEL%d\n", current_el());
#if defined(CONFIG_FPGA) && defined(CONFIG_FPGA_ZYNQMPPL) && \
--
2.17.1
More information about the U-Boot
mailing list