x86: qemu: split qfw command interface and qfw core

This patch splits qfw command interface and qfw core function into two
files, and introduces a new Kconfig option (CONFIG_QFW) for qfw core.

Now when qfw command interface is enabled, it will automatically select
qfw core. This patch also makes the ACPI table generation select
CONFIG_QFW.

Signed-off-by: Miao Yan <yanmiaobest@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

3 files changed, 191 insertions, 0 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index af8667f..fa53700 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -138,4 +138,10 @@ config WINBOND_W83627
 	  legacy UART or other devices in the Winbond Super IO chips
 	  on X86 platforms.
 
+config QFW
+	bool
+	help
+	  Hidden option to enable QEMU fw_cfg interface. This will be selected by
+	  either CONFIG_CMD_QEMU_FW_CFG or CONFIG_GENERATE_ACPI_TABLE.
+
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 5969d34..4893086 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -43,3 +43,4 @@ obj-$(CONFIG_PCA9551_LED) += pca9551_led.o
 obj-$(CONFIG_RESET) += reset-uclass.o
 obj-$(CONFIG_FSL_DEVICE_DISABLE) += fsl_devdis.o
 obj-$(CONFIG_WINBOND_W83627) += winbond_w83627.o
+obj-$(CONFIG_QFW) += qemu_fw_cfg.o
diff --git a/drivers/misc/qemu_fw_cfg.c b/drivers/misc/qemu_fw_cfg.c
new file mode 100644
index 0000000..a574bd1
--- /dev/null
+++ b/drivers/misc/qemu_fw_cfg.c
@@ -0,0 +1,184 @@
+/*
+ * (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <errno.h>
+#include <malloc.h>
+#include <qemu_fw_cfg.h>
+#include <asm/io.h>
+#include <linux/list.h>
+
+static bool fwcfg_present;
+static bool fwcfg_dma_present;
+
+static LIST_HEAD(fw_list);
+
+/* Read configuration item using fw_cfg PIO interface */
+static void qemu_fwcfg_read_entry_pio(uint16_t entry,
+		uint32_t size, void *address)
+{
+	uint32_t i = 0;
+	uint8_t *data = address;
+
+	/*
+	 * writting FW_CFG_INVALID will cause read operation to resume at
+	 * last offset, otherwise read will start at offset 0
+	 */
+	if (entry != FW_CFG_INVALID)
+		outw(entry, FW_CONTROL_PORT);
+	while (size--)
+		data[i++] = inb(FW_DATA_PORT);
+}
+
+/* Read configuration item using fw_cfg DMA interface */
+static void qemu_fwcfg_read_entry_dma(uint16_t entry,
+		uint32_t size, void *address)
+{
+	struct fw_cfg_dma_access dma;
+
+	dma.length = cpu_to_be32(size);
+	dma.address = cpu_to_be64((uintptr_t)address);
+	dma.control = cpu_to_be32(FW_CFG_DMA_READ);
+
+	/*
+	 * writting FW_CFG_INVALID will cause read operation to resume at
+	 * last offset, otherwise read will start at offset 0
+	 */
+	if (entry != FW_CFG_INVALID)
+		dma.control |= cpu_to_be32(FW_CFG_DMA_SELECT | (entry << 16));
+
+	barrier();
+
+	debug("qemu_fwcfg_dma_read_entry: addr %p, length %u control 0x%x\n",
+	      address, size, be32_to_cpu(dma.control));
+
+	outl(cpu_to_be32((uint32_t)&dma), FW_DMA_PORT_HIGH);
+
+	while (be32_to_cpu(dma.control) & ~FW_CFG_DMA_ERROR)
+		__asm__ __volatile__ ("pause");
+}
+
+bool qemu_fwcfg_present(void)
+{
+	return fwcfg_present;
+}
+
+bool qemu_fwcfg_dma_present(void)
+{
+	return fwcfg_dma_present;
+}
+
+void qemu_fwcfg_read_entry(uint16_t entry, uint32_t length, void *address)
+{
+	if (fwcfg_dma_present)
+		qemu_fwcfg_read_entry_dma(entry, length, address);
+	else
+		qemu_fwcfg_read_entry_pio(entry, length, address);
+}
+
+int qemu_fwcfg_online_cpus(void)
+{
+	uint16_t nb_cpus;
+
+	if (!fwcfg_present)
+		return -ENODEV;
+
+	qemu_fwcfg_read_entry(FW_CFG_NB_CPUS, 2, &nb_cpus);
+
+	return le16_to_cpu(nb_cpus);
+}
+
+int qemu_fwcfg_read_firmware_list(void)
+{
+	int i;
+	uint32_t count;
+	struct fw_file *file;
+	struct list_head *entry;
+
+	/* don't read it twice */
+	if (!list_empty(&fw_list))
+		return 0;
+
+	qemu_fwcfg_read_entry(FW_CFG_FILE_DIR, 4, &count);
+	if (!count)
+		return 0;
+
+	count = be32_to_cpu(count);
+	for (i = 0; i < count; i++) {
+		file = malloc(sizeof(*file));
+		if (!file) {
+			printf("error: allocating resource\n");
+			goto err;
+		}
+		qemu_fwcfg_read_entry(FW_CFG_INVALID,
+				      sizeof(struct fw_cfg_file), &file->cfg);
+		file->addr = 0;
+		list_add_tail(&file->list, &fw_list);
+	}
+
+	return 0;
+
+err:
+	list_for_each(entry, &fw_list) {
+		file = list_entry(entry, struct fw_file, list);
+		free(file);
+	}
+
+	return -ENOMEM;
+}
+
+struct fw_file *qemu_fwcfg_find_file(const char *name)
+{
+	struct list_head *entry;
+	struct fw_file *file;
+
+	list_for_each(entry, &fw_list) {
+		file = list_entry(entry, struct fw_file, list);
+		if (!strcmp(file->cfg.name, name))
+			return file;
+	}
+
+	return NULL;
+}
+
+struct fw_file *qemu_fwcfg_file_iter_init(struct fw_cfg_file_iter *iter)
+{
+	iter->entry = fw_list.next;
+	return list_entry((struct list_head *)iter->entry,
+			  struct fw_file, list);
+}
+
+struct fw_file *qemu_fwcfg_file_iter_next(struct fw_cfg_file_iter *iter)
+{
+	iter->entry = ((struct list_head *)iter->entry)->next;
+	return list_entry((struct list_head *)iter->entry,
+			  struct fw_file, list);
+}
+
+bool qemu_fwcfg_file_iter_end(struct fw_cfg_file_iter *iter)
+{
+	return iter->entry == &fw_list;
+}
+
+void qemu_fwcfg_init(void)
+{
+	uint32_t qemu;
+	uint32_t dma_enabled;
+
+	fwcfg_present = false;
+	fwcfg_dma_present = false;
+
+	qemu_fwcfg_read_entry_pio(FW_CFG_SIGNATURE, 4, &qemu);
+	if (be32_to_cpu(qemu) == QEMU_FW_CFG_SIGNATURE)
+		fwcfg_present = true;
+
+	if (fwcfg_present) {
+		qemu_fwcfg_read_entry_pio(FW_CFG_ID, 1, &dma_enabled);
+		if (dma_enabled & FW_CFG_DMA_ENABLED)
+			fwcfg_dma_present = true;
+	}
+}