hw/ppc/e500: Implement pflash handling
Allows e500 boards to have their root file system reside on flash using
only builtin devices located in the eLBC memory region.
Note that the flash memory area is only created when a -pflash argument is
given, and that the size is determined by the given file. The idea is to
put users into control.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221018210146.193159-6-shentey@gmail.com>
[danielhb: use memory_region_size() in mmio_size]
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
diff --git a/docs/system/ppc/ppce500.rst b/docs/system/ppc/ppce500.rst
index 7b5eb3c..fa40e57 100644
--- a/docs/system/ppc/ppce500.rst
+++ b/docs/system/ppc/ppce500.rst
@@ -165,3 +165,18 @@
.. code-block:: bash
-netdev tap,ifname=tap0,script=no,downscript=no,id=net0 -device eTSEC,netdev=net0
+
+Root file system on flash drive
+-------------------------------
+
+Rather than using a root file system on ram disk, it is possible to have it on
+CFI flash. Given an ext2 image whose size must be a power of two, it can be used
+as follows:
+
+.. code-block:: bash
+
+ $ qemu-system-ppc64 -M ppce500 -cpu e500mc -smp 4 -m 2G \
+ -display none -serial stdio \
+ -kernel vmlinux \
+ -drive if=pflash,file=/path/to/rootfs.ext2,format=raw \
+ -append "rootwait root=/dev/mtdblock0"
diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
index 791fe78..769a1ea 100644
--- a/hw/ppc/Kconfig
+++ b/hw/ppc/Kconfig
@@ -126,6 +126,7 @@
select ETSEC
select GPIO_MPC8XXX
select OPENPIC
+ select PFLASH_CFI01
select PLATFORM_BUS
select PPCE500_PCI
select SERIAL
diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index 3e950ea..2fe4966 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -23,8 +23,10 @@
#include "e500-ccsr.h"
#include "net/net.h"
#include "qemu/config-file.h"
+#include "hw/block/flash.h"
#include "hw/char/serial.h"
#include "hw/pci/pci.h"
+#include "sysemu/block-backend-io.h"
#include "sysemu/sysemu.h"
#include "sysemu/kvm.h"
#include "sysemu/reset.h"
@@ -267,6 +269,31 @@
}
}
+static void create_devtree_flash(SysBusDevice *sbdev,
+ PlatformDevtreeData *data)
+{
+ g_autofree char *name = NULL;
+ uint64_t num_blocks = object_property_get_uint(OBJECT(sbdev),
+ "num-blocks",
+ &error_fatal);
+ uint64_t sector_length = object_property_get_uint(OBJECT(sbdev),
+ "sector-length",
+ &error_fatal);
+ uint64_t bank_width = object_property_get_uint(OBJECT(sbdev),
+ "width",
+ &error_fatal);
+ hwaddr flashbase = 0;
+ hwaddr flashsize = num_blocks * sector_length;
+ void *fdt = data->fdt;
+
+ name = g_strdup_printf("%s/nor@%" PRIx64, data->node, flashbase);
+ qemu_fdt_add_subnode(fdt, name);
+ qemu_fdt_setprop_string(fdt, name, "compatible", "cfi-flash");
+ qemu_fdt_setprop_sized_cells(fdt, name, "reg",
+ 1, flashbase, 1, flashsize);
+ qemu_fdt_setprop_cell(fdt, name, "bank-width", bank_width);
+}
+
static void platform_bus_create_devtree(PPCE500MachineState *pms,
void *fdt, const char *mpic)
{
@@ -276,6 +303,8 @@
uint64_t addr = pmc->platform_bus_base;
uint64_t size = pmc->platform_bus_size;
int irq_start = pmc->platform_bus_first_irq;
+ SysBusDevice *sbdev;
+ bool ambiguous;
/* Create a /platform node that we can put all devices into */
@@ -302,6 +331,13 @@
/* Loop through all dynamic sysbus devices and create nodes for them */
foreach_dynamic_sysbus_device(sysbus_device_create_devtree, &data);
+ sbdev = SYS_BUS_DEVICE(object_resolve_path_type("", TYPE_PFLASH_CFI01,
+ &ambiguous));
+ if (sbdev) {
+ assert(!ambiguous);
+ create_devtree_flash(sbdev, &data);
+ }
+
g_free(node);
}
@@ -856,6 +892,7 @@
unsigned int pci_irq_nrs[PCI_NUM_PINS] = {1, 2, 3, 4};
IrqLines *irqs;
DeviceState *dev, *mpicdev;
+ DriveInfo *dinfo;
CPUPPCState *firstenv = NULL;
MemoryRegion *ccsr_addr_space;
SysBusDevice *s;
@@ -1024,6 +1061,48 @@
pmc->platform_bus_base,
&pms->pbus_dev->mmio);
+ dinfo = drive_get(IF_PFLASH, 0, 0);
+ if (dinfo) {
+ BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
+ BlockDriverState *bs = blk_bs(blk);
+ uint64_t mmio_size = memory_region_size(&pms->pbus_dev->mmio);
+ uint64_t size = bdrv_getlength(bs);
+ uint32_t sector_len = 64 * KiB;
+
+ if (!is_power_of_2(size)) {
+ error_report("Size of pflash file must be a power of two.");
+ exit(1);
+ }
+
+ if (size > mmio_size) {
+ error_report("Size of pflash file must not be bigger than %" PRIu64
+ " bytes.", mmio_size);
+ exit(1);
+ }
+
+ if (!QEMU_IS_ALIGNED(size, sector_len)) {
+ error_report("Size of pflash file must be a multiple of %" PRIu32
+ ".", sector_len);
+ exit(1);
+ }
+
+ dev = qdev_new(TYPE_PFLASH_CFI01);
+ qdev_prop_set_drive(dev, "drive", blk);
+ qdev_prop_set_uint32(dev, "num-blocks", size / sector_len);
+ qdev_prop_set_uint64(dev, "sector-length", sector_len);
+ qdev_prop_set_uint8(dev, "width", 2);
+ qdev_prop_set_bit(dev, "big-endian", true);
+ qdev_prop_set_uint16(dev, "id0", 0x89);
+ qdev_prop_set_uint16(dev, "id1", 0x18);
+ qdev_prop_set_uint16(dev, "id2", 0x0000);
+ qdev_prop_set_uint16(dev, "id3", 0x0);
+ qdev_prop_set_string(dev, "name", "e500.flash");
+ sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
+
+ memory_region_add_subregion(&pms->pbus_dev->mmio, 0,
+ pflash_cfi01_get_memory(PFLASH_CFI01(dev)));
+ }
+
/*
* Smart firmware defaults ahead!
*
