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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/drivers/nvs/threewire.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/drivers/nvs/threewire.c')
-rw-r--r--qemu/roms/ipxe/src/drivers/nvs/threewire.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/drivers/nvs/threewire.c b/qemu/roms/ipxe/src/drivers/nvs/threewire.c
new file mode 100644
index 000000000..53f1ad8de
--- /dev/null
+++ b/qemu/roms/ipxe/src/drivers/nvs/threewire.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stddef.h>
+#include <string.h>
+#include <assert.h>
+#include <unistd.h>
+#include <ipxe/threewire.h>
+
+/** @file
+ *
+ * Three-wire serial devices
+ *
+ */
+
+/**
+ * Read data from three-wire device
+ *
+ * @v nvs NVS device
+ * @v address Address from which to read
+ * @v data Data buffer
+ * @v len Length of data buffer
+ * @ret rc Return status code
+ */
+int threewire_read ( struct nvs_device *nvs, unsigned int address,
+ void *data, size_t len ) {
+ struct spi_device *device = nvs_to_spi ( nvs );
+ struct spi_bus *bus = device->bus;
+ int rc;
+
+ assert ( bus->mode == SPI_MODE_THREEWIRE );
+
+ DBGC ( device, "3wire %p reading %zd bytes at %04x\n",
+ device, len, address );
+
+ if ( ( rc = bus->rw ( bus, device, THREEWIRE_READ, address,
+ NULL, data, len ) ) != 0 ) {
+ DBGC ( device, "3wire %p could not read: %s\n",
+ device, strerror ( rc ) );
+ return rc;
+ }
+
+ return 0;
+}
+
+/**
+ * Write data to three-wire device
+ *
+ * @v nvs NVS device
+ * @v address Address from which to read
+ * @v data Data buffer
+ * @v len Length of data buffer
+ * @ret rc Return status code
+ */
+int threewire_write ( struct nvs_device *nvs, unsigned int address,
+ const void *data, size_t len ) {
+ struct spi_device *device = nvs_to_spi ( nvs );
+ struct spi_bus *bus = device->bus;
+ int rc;
+
+ assert ( bus->mode == SPI_MODE_THREEWIRE );
+
+ DBGC ( device, "3wire %p writing %zd bytes at %04x\n",
+ device, len, address );
+
+ /* Enable device for writing */
+ if ( ( rc = bus->rw ( bus, device, THREEWIRE_EWEN,
+ THREEWIRE_EWEN_ADDRESS, NULL, NULL, 0 ) ) != 0 ){
+ DBGC ( device, "3wire %p could not enable writing: %s\n",
+ device, strerror ( rc ) );
+ return rc;
+ }
+
+ /* Write data */
+ if ( ( rc = bus->rw ( bus, device, THREEWIRE_WRITE, address,
+ data, NULL, len ) ) != 0 ) {
+ DBGC ( device, "3wire %p could not write: %s\n",
+ device, strerror ( rc ) );
+ return rc;
+ }
+
+ /* Our model of an SPI bus doesn't provide a mechanism for
+ * "assert CS, wait for MISO to become high, so just wait for
+ * long enough to ensure that the write has completed.
+ */
+ mdelay ( THREEWIRE_WRITE_MDELAY );
+
+ return 0;
+}
+
+/**
+ * Autodetect device address length
+ *
+ * @v device SPI device
+ * @ret rc Return status code
+ */
+int threewire_detect_address_len ( struct spi_device *device ) {
+ struct nvs_device *nvs = &device->nvs;
+ int rc;
+
+ DBGC ( device, "3wire %p autodetecting address length\n", device );
+
+ device->address_len = SPI_AUTODETECT_ADDRESS_LEN;
+ if ( ( rc = threewire_read ( nvs, 0, NULL,
+ ( 1 << nvs->word_len_log2 ) ) ) != 0 ) {
+ DBGC ( device, "3wire %p could not autodetect address "
+ "length: %s\n", device, strerror ( rc ) );
+ return rc;
+ }
+
+ DBGC ( device, "3wire %p autodetected address length %d\n",
+ device, device->address_len );
+ return 0;
+}