[U-Boot] [PATCH v3 1/7] efi_loader: Add network access support
Simon Glass
sjg at chromium.org
Mon May 16 15:24:02 CEST 2016
Hi Alexander,
On 14 May 2016 at 14:34, Alexander Graf <agraf at suse.de> wrote:
>
>
>> Am 14.05.2016 um 21:49 schrieb Simon Glass <sjg at chromium.org>:
>>
>> Hi Alexander,
>>
>>> On 10 May 2016 at 15:25, Alexander Graf <agraf at suse.de> wrote:
>>> We can now successfully boot EFI applications from disk, but users
>>> may want to also run them from a PXE setup.
>>>
>>> This patch implements rudimentary network support, allowing a payload
>>> to send and receive network packets.
>>>
>>> With this patch, I was able to successfully run grub2 with network
>>> access inside of QEMU's -M xlnx-ep108 and on a zcu102 system.
>>>
>>> Signed-off-by: Alexander Graf <agraf at suse.de>
>>>
>>> ---
>>>
>>> v2 -> v3:
>>>
>>> - Align initialization sequence with net code
>>> - Set device to initialized after init call
>>> - Align tx buffers to DMA alignment (rx gets memcpy'd)
>>> - Add comment about eth_rx()
>>> ---
>>> cmd/bootefi.c | 7 ++
>>> include/efi_api.h | 119 ++++++++++++++++++
>>> include/efi_loader.h | 7 ++
>>> include/net.h | 2 +-
>>> lib/efi_loader/Makefile | 1 +
>>> lib/efi_loader/efi_net.c | 314 +++++++++++++++++++++++++++++++++++++++++++++++
>>> net/bootp.c | 2 +
>>> net/net.c | 4 +-
>>> net/tftp.c | 2 +
>>> 9 files changed, 455 insertions(+), 3 deletions(-)
>>> create mode 100644 lib/efi_loader/efi_net.c
>>>
>>> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
>>> index 7f552fc..d3a2331 100644
>>> --- a/cmd/bootefi.c
>>> +++ b/cmd/bootefi.c
>>> @@ -197,6 +197,13 @@ static unsigned long do_bootefi_exec(void *efi, void *fdt)
>>> #ifdef CONFIG_LCD
>>> efi_gop_register();
>>> #endif
>>> +#ifdef CONFIG_NET
>>> + void *nethandle = loaded_image_info.device_handle;
>>> + efi_net_register(&nethandle);
>>> +
>>> + if (!memcmp(bootefi_device_path[0].str, "N\0e\0t", 6))
>>> + loaded_image_info.device_handle = nethandle;
>>> +#endif
>>>
>>> /* Call our payload! */
>>> #ifdef DEBUG_EFI
>>> diff --git a/include/efi_api.h b/include/efi_api.h
>>> index 51d7586..20035d7 100644
>>> --- a/include/efi_api.h
>>> +++ b/include/efi_api.h
>>> @@ -412,4 +412,123 @@ struct efi_gop
>>> struct efi_gop_mode *mode;
>>> };
>>>
>>> +#define EFI_SIMPLE_NETWORK_GUID \
>>> + EFI_GUID(0xa19832b9, 0xac25, 0x11d3, \
>>> + 0x9a, 0x2d, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
>>> +
>>> +struct efi_mac_address {
>>> + char mac_addr[32];
>>> +};
>>> +
>>> +struct efi_ip_address {
>>> + u8 ip_addr[16];
>>> +};
>>> +
>>> +enum efi_simple_network_state {
>>> + EFI_NETWORK_STOPPED,
>>> + EFI_NETWORK_STARTED,
>>> + EFI_NETWORK_INITIALIZED,
>>> +};
>>> +
>>> +struct efi_simple_network_mode {
>>> + enum efi_simple_network_state state;
>>> + u32 hwaddr_size;
>>> + u32 media_header_size;
>>> + u32 max_packet_size;
>>> + u32 nvram_size;
>>> + u32 nvram_access_size;
>>> + u32 receive_filter_mask;
>>> + u32 receive_filter_setting;
>>> + u32 max_mcast_filter_count;
>>> + u32 mcast_filter_count;
>>> + struct efi_mac_address mcast_filter[16];
>>> + struct efi_mac_address current_address;
>>> + struct efi_mac_address broadcast_address;
>>> + struct efi_mac_address permanent_address;
>>> + u8 if_type;
>>> + u8 mac_changeable;
>>> + u8 multitx_supported;
>>> + u8 media_present_supported;
>>> + u8 media_present;
>>> +};
>>> +
>>> +#define EFI_SIMPLE_NETWORK_RECEIVE_UNICAST 0x01,
>>> +#define EFI_SIMPLE_NETWORK_RECEIVE_MULTICAST 0x02,
>>> +#define EFI_SIMPLE_NETWORK_RECEIVE_BROADCAST 0x04,
>>> +#define EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS 0x08,
>>> +#define EFI_SIMPLE_NETWORK_RECEIVE_PROMISCUOUS_MULTICAST 0x10,
>>> +
>>> +struct efi_simple_network
>>> +{
>>> + u64 revision;
>>> + efi_status_t (EFIAPI *start)(struct efi_simple_network *this);
>>> + efi_status_t (EFIAPI *stop)(struct efi_simple_network *this);
>>> + efi_status_t (EFIAPI *initialize)(struct efi_simple_network *this,
>>> + ulong extra_rx, ulong extra_tx);
>>> + efi_status_t (EFIAPI *reset)(struct efi_simple_network *this,
>>> + int extended_verification);
>>> + efi_status_t (EFIAPI *shutdown)(struct efi_simple_network *this);
>>> + efi_status_t (EFIAPI *receive_filters)(struct efi_simple_network *this,
>>> + u32 enable, u32 disable, int reset_mcast_filter,
>>> + ulong mcast_filter_count,
>>> + struct efi_mac_address *mcast_filter);
>>> + efi_status_t (EFIAPI *station_address)(struct efi_simple_network *this,
>>> + int reset, struct efi_mac_address *new_mac);
>>> + efi_status_t (EFIAPI *statistics)(struct efi_simple_network *this,
>>> + int reset, ulong *stat_size, void *stat_table);
>>> + efi_status_t (EFIAPI *mcastiptomac)(struct efi_simple_network *this,
>>> + int ipv6, struct efi_ip_address *ip,
>>> + struct efi_mac_address *mac);
>>> + efi_status_t (EFIAPI *nvdata)(struct efi_simple_network *this,
>>> + int read_write, ulong offset, ulong buffer_size,
>>> + char *buffer);
>>> + efi_status_t (EFIAPI *get_status)(struct efi_simple_network *this,
>>> + u32 *int_status, void **txbuf);
>>> + efi_status_t (EFIAPI *transmit)(struct efi_simple_network *this,
>>> + ulong header_size, ulong buffer_size, void *buffer,
>>> + struct efi_mac_address *src_addr,
>>> + struct efi_mac_address *dest_addr, u16 *protocol);
>>> + efi_status_t (EFIAPI *receive)(struct efi_simple_network *this,
>>> + ulong *header_size, ulong *buffer_size, void *buffer,
>>> + struct efi_mac_address *src_addr,
>>> + struct efi_mac_address *dest_addr, u16 *protocol);
>>> + void (EFIAPI *waitforpacket)(void);
>>> + struct efi_simple_network_mode *mode;
>>> +};
>>> +
>>> +#define EFI_PXE_GUID \
>>> + EFI_GUID(0x03c4e603, 0xac28, 0x11d3, \
>>> + 0x9a, 0x2d, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
>>> +
>>> +struct efi_pxe_packet {
>>> + u8 packet[1472];
>>> +};
>>> +
>>> +struct efi_pxe_mode
>>> +{
>>> + u8 unused[52];
>>> + struct efi_pxe_packet dhcp_discover;
>>> + struct efi_pxe_packet dhcp_ack;
>>> + struct efi_pxe_packet proxy_offer;
>>> + struct efi_pxe_packet pxe_discover;
>>> + struct efi_pxe_packet pxe_reply;
>>> +};
>>> +
>>> +struct efi_pxe {
>>> + u64 rev;
>>> + void (EFIAPI *start)(void);
>>> + void (EFIAPI *stop)(void);
>>> + void (EFIAPI *dhcp)(void);
>>> + void (EFIAPI *discover)(void);
>>> + void (EFIAPI *mftp)(void);
>>> + void (EFIAPI *udpwrite)(void);
>>> + void (EFIAPI *udpread)(void);
>>> + void (EFIAPI *setipfilter)(void);
>>> + void (EFIAPI *arp)(void);
>>> + void (EFIAPI *setparams)(void);
>>> + void (EFIAPI *setstationip)(void);
>>> + void (EFIAPI *setpackets)(void);
>>> + struct efi_pxe_mode *mode;
>>> +};
>>> +
>>> #endif
>>> diff --git a/include/efi_loader.h b/include/efi_loader.h
>>> index 88b8149..8005454 100644
>>> --- a/include/efi_loader.h
>>> +++ b/include/efi_loader.h
>>> @@ -91,6 +91,12 @@ extern struct list_head efi_obj_list;
>>> int efi_disk_register(void);
>>> /* Called by bootefi to make GOP (graphical) interface available */
>>> int efi_gop_register(void);
>>> +/* Called by bootefi to make the network interface available */
>>> +int efi_net_register(void **handle);
>>> +
>>> +/* Called by networking code to memorize the dhcp ack package */
>>> +void efi_net_set_dhcp_ack(void *pkt, int len);
>>> +
>>> /*
>>> * Stub implementation for a protocol opener that just returns the handle as
>>> * interface
>>> @@ -157,5 +163,6 @@ static inline void ascii2unicode(u16 *unicode, char *ascii)
>>> static inline void efi_restore_gd(void) { }
>>> static inline void efi_set_bootdev(const char *dev, const char *devnr,
>>> const char *path) { }
>>> +static inline void efi_net_set_dhcp_ack(void *pkt, int len) { }
>>>
>>> #endif
>>> diff --git a/include/net.h b/include/net.h
>>> index 05800c4..5ee5929 100644
>>> --- a/include/net.h
>>> +++ b/include/net.h
>>> @@ -269,7 +269,7 @@ int eth_getenv_enetaddr_by_index(const char *base_name, int index,
>>> int eth_init(void); /* Initialize the device */
>>> int eth_send(void *packet, int length); /* Send a packet */
>>>
>>> -#ifdef CONFIG_API
>>> +#if defined(CONFIG_API) || defined(CONFIG_EFI_LOADER)
>>> int eth_receive(void *packet, int length); /* Receive a packet*/
>>> extern void (*push_packet)(void *packet, int length);
>>> #endif
>>> diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile
>>> index 83e31f6..2a3849e 100644
>>> --- a/lib/efi_loader/Makefile
>>> +++ b/lib/efi_loader/Makefile
>>> @@ -11,3 +11,4 @@ obj-y += efi_image_loader.o efi_boottime.o efi_runtime.o efi_console.o
>>> obj-y += efi_memory.o
>>> obj-$(CONFIG_LCD) += efi_gop.o
>>> obj-$(CONFIG_PARTITIONS) += efi_disk.o
>>> +obj-$(CONFIG_NET) += efi_net.o
>>> diff --git a/lib/efi_loader/efi_net.c b/lib/efi_loader/efi_net.c
>>> new file mode 100644
>>> index 0000000..a95ff3c
>>> --- /dev/null
>>> +++ b/lib/efi_loader/efi_net.c
>>> @@ -0,0 +1,314 @@
>>> +/*
>>> + * EFI application network access support
>>> + *
>>> + * Copyright (c) 2016 Alexander Graf
>>> + *
>>> + * SPDX-License-Identifier: GPL-2.0+
>>> + */
>>> +
>>> +#include <common.h>
>>> +#include <efi_loader.h>
>>> +#include <inttypes.h>
>>> +#include <lcd.h>
>>> +#include <malloc.h>
>>> +
>>> +DECLARE_GLOBAL_DATA_PTR;
>>> +
>>> +static const efi_guid_t efi_net_guid = EFI_SIMPLE_NETWORK_GUID;
>>> +static const efi_guid_t efi_pxe_guid = EFI_PXE_GUID;
>>> +static struct efi_pxe_packet *dhcp_ack;
>>> +static bool new_rx_packet;
>>> +static void *new_tx_packet;
>>> +
>>> +struct efi_net_obj {
>>> + /* Generic EFI object parent class data */
>>> + struct efi_object parent;
>>> + /* EFI Interface callback struct for network */
>>> + struct efi_simple_network net;
>>> + struct efi_simple_network_mode net_mode;
>>> + /* Device path to the network adapter */
>>> + struct efi_device_path_file_path dp[2];
>>> + /* PXE struct to transmit dhcp data */
>>> + struct efi_pxe pxe;
>>> + struct efi_pxe_mode pxe_mode;
>>> +};
>>> +
>>> +static efi_status_t EFIAPI efi_net_start(struct efi_simple_network *this)
>>> +{
>>> + EFI_ENTRY("%p", this);
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_stop(struct efi_simple_network *this)
>>> +{
>>> + EFI_ENTRY("%p", this);
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_initialize(struct efi_simple_network *this,
>>> + ulong extra_rx, ulong extra_tx)
>>> +{
>>> + struct efi_net_obj *netobj = container_of(this, struct efi_net_obj, net);
>>> + int ret;
>>> + EFI_ENTRY("%p, %lx, %lx", this, extra_rx, extra_tx);
>>> +
>>> + eth_halt();
>>> + eth_set_current();
>>> + ret = eth_init();
>>> + if (ret < 0) {
>>> + eth_halt();
>>> + return EFI_EXIT(EFI_DEVICE_ERROR);
>>> + }
>>> +
>>> + netobj->net_mode.state = EFI_NETWORK_INITIALIZED;
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_reset(struct efi_simple_network *this,
>>> + int extended_verification)
>>> +{
>>> + EFI_ENTRY("%p, %x", this, extended_verification);
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_shutdown(struct efi_simple_network *this)
>>> +{
>>> + EFI_ENTRY("%p", this);
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_receive_filters(
>>> + struct efi_simple_network *this, u32 enable, u32 disable,
>>> + int reset_mcast_filter, ulong mcast_filter_count,
>>> + struct efi_mac_address *mcast_filter)
>>> +{
>>> + EFI_ENTRY("%p, %x, %x, %x, %lx, %p", this, enable, disable,
>>> + reset_mcast_filter, mcast_filter_count, mcast_filter);
>>> +
>>> + /* XXX Do we care? */
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_station_address(
>>> + struct efi_simple_network *this, int reset,
>>> + struct efi_mac_address *new_mac)
>>> +{
>>> + EFI_ENTRY("%p, %x, %p", this, reset, new_mac);
>>> +
>>> + return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_statistics(struct efi_simple_network *this,
>>> + int reset, ulong *stat_size,
>>> + void *stat_table)
>>> +{
>>> + EFI_ENTRY("%p, %x, %p, %p", this, reset, stat_size, stat_table);
>>> +
>>> + return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_mcastiptomac(struct efi_simple_network *this,
>>> + int ipv6,
>>> + struct efi_ip_address *ip,
>>> + struct efi_mac_address *mac)
>>> +{
>>> + EFI_ENTRY("%p, %x, %p, %p", this, ipv6, ip, mac);
>>> +
>>> + return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_nvdata(struct efi_simple_network *this,
>>> + int read_write, ulong offset,
>>> + ulong buffer_size, char *buffer)
>>> +{
>>> + EFI_ENTRY("%p, %x, %lx, %lx, %p", this, read_write, offset, buffer_size,
>>> + buffer);
>>> +
>>> + return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_get_status(struct efi_simple_network *this,
>>> + u32 *int_status, void **txbuf)
>>> +{
>>> + EFI_ENTRY("%p, %p, %p", this, int_status, txbuf);
>>> +
>>> + /* We send packets synchronously, so nothing is outstanding */
>>> + if (int_status)
>>> + *int_status = 0;
>>> + if (txbuf)
>>> + *txbuf = new_tx_packet;
>>> +
>>> + new_tx_packet = NULL;
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_transmit(struct efi_simple_network *this,
>>> + ulong header_size, ulong buffer_size, void *buffer,
>>> + struct efi_mac_address *src_addr,
>>> + struct efi_mac_address *dest_addr, u16 *protocol)
>>> +{
>>> + EFI_ENTRY("%p, %lx, %lx, %p, %p, %p, %p", this, header_size,
>>> + buffer_size, buffer, src_addr, dest_addr, protocol);
>>> +
>>> + if (header_size) {
>>> + /* We would need to create the header if header_size != 0 */
>>> + return EFI_EXIT(EFI_INVALID_PARAMETER);
>>> + }
>>> +
>>> + /*
>>> + * Some drivers need to have DMA aligned buffers, so if
>>> + * it's misaligned, let's use our own.
>>> + */
>>> + if ((ulong)buffer & (ARCH_DMA_MINALIGN - 1)) {
>>> + void *packet = memalign(ARCH_DMA_MINALIGN, buffer_size);
>>> + memcpy(packet, buffer, buffer_size);
>>> + net_send_packet(packet, buffer_size);
>>> + free(packet);
>>> + } else {
>>> + net_send_packet(buffer, buffer_size);
>>> + }
>>> +
>>> + new_tx_packet = buffer;
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static void efi_net_push(void *pkt, int len)
>>> +{
>>> + new_rx_packet = true;
>>> +}
>>> +
>>> +static efi_status_t EFIAPI efi_net_receive(struct efi_simple_network *this,
>>> + ulong *header_size, ulong *buffer_size, void *buffer,
>>> + struct efi_mac_address *src_addr,
>>> + struct efi_mac_address *dest_addr, u16 *protocol)
>>> +{
>>> + EFI_ENTRY("%p, %p, %p, %p, %p, %p, %p", this, header_size,
>>> + buffer_size, buffer, src_addr, dest_addr, protocol);
>>> +
>>> + push_packet = efi_net_push;
>>> + /* XXX With device model this reads multiple packets, we only want 1 */
>>> + eth_rx();
>>> + push_packet = NULL;
>>> +
>>> + if (!new_rx_packet)
>>> + return EFI_EXIT(EFI_NOT_READY);
>>> +
>>> + if (*buffer_size < net_rx_packet_len) {
>>> + /* Packet doesn't fit, try again with bigger buf */
>>> + *buffer_size = net_rx_packet_len;
>>> + return EFI_EXIT(EFI_BUFFER_TOO_SMALL);
>>> + }
>>> +
>>> + memcpy(buffer, net_rx_packet, net_rx_packet_len);
>>> + *buffer_size = net_rx_packet_len;
>>> + new_rx_packet = false;
>>> +
>>> + return EFI_EXIT(EFI_SUCCESS);
>>> +}
>>> +
>>> +static efi_status_t efi_net_open_dp(void *handle, efi_guid_t *protocol,
>>> + void **protocol_interface, void *agent_handle,
>>> + void *controller_handle, uint32_t attributes)
>>> +{
>>> + struct efi_simple_network *net = handle;
>>> + struct efi_net_obj *netobj = container_of(net, struct efi_net_obj, net);
>>> +
>>> + *protocol_interface = netobj->dp;
>>> +
>>> + return EFI_SUCCESS;
>>> +}
>>> +
>>> +static efi_status_t efi_net_open_pxe(void *handle, efi_guid_t *protocol,
>>> + void **protocol_interface, void *agent_handle,
>>> + void *controller_handle, uint32_t attributes)
>>> +{
>>> + struct efi_simple_network *net = handle;
>>> + struct efi_net_obj *netobj = container_of(net, struct efi_net_obj, net);
>>> +
>>> + *protocol_interface = &netobj->pxe;
>>> +
>>> + return EFI_SUCCESS;
>>> +}
>>> +
>>> +void efi_net_set_dhcp_ack(void *pkt, int len)
>>> +{
>>> + int maxsize = sizeof(*dhcp_ack);
>>> +
>>> + if (!dhcp_ack)
>>> + dhcp_ack = malloc(maxsize);
>>> +
>>> + memcpy(dhcp_ack, pkt, min(len, maxsize));
>>> +}
>>> +
>>> +/* This gets called from do_bootefi_exec(). */
>>> +int efi_net_register(void **handle)
>>> +{
>>> + struct efi_net_obj *netobj;
>>> + struct efi_device_path_file_path dp_net = {
>>> + .dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
>>> + .dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
>>> + .dp.length = sizeof(dp_net),
>>> + .str = { 'N', 'e', 't' },
>>> + };
>>> + struct efi_device_path_file_path dp_end = {
>>> + .dp.type = DEVICE_PATH_TYPE_END,
>>> + .dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
>>> + .dp.length = sizeof(dp_end),
>>> + };
>>> +
>>> + if (!eth_get_dev()) {
>>> + /* No eth device active, don't expose any */
>>> + return 0;
>>> + }
>>> +
>>> + /* We only expose the "active" eth device, so one is enough */
>>> + netobj = calloc(1, sizeof(*netobj));
>>> +
>>> + /* Fill in object data */
>>> + netobj->parent.protocols[0].guid = &efi_net_guid;
>>> + netobj->parent.protocols[0].open = efi_return_handle;
>>> + netobj->parent.protocols[1].guid = &efi_guid_device_path;
>>> + netobj->parent.protocols[1].open = efi_net_open_dp;
>>> + netobj->parent.protocols[2].guid = &efi_pxe_guid;
>>> + netobj->parent.protocols[2].open = efi_net_open_pxe;
>>> + netobj->parent.handle = &netobj->net;
>>> + netobj->net.start = efi_net_start;
>>> + netobj->net.stop = efi_net_stop;
>>> + netobj->net.initialize = efi_net_initialize;
>>> + netobj->net.reset = efi_net_reset;
>>> + netobj->net.shutdown = efi_net_shutdown;
>>> + netobj->net.receive_filters = efi_net_receive_filters;
>>> + netobj->net.station_address = efi_net_station_address;
>>> + netobj->net.statistics = efi_net_statistics;
>>> + netobj->net.mcastiptomac = efi_net_mcastiptomac;
>>> + netobj->net.nvdata = efi_net_nvdata;
>>> + netobj->net.get_status = efi_net_get_status;
>>> + netobj->net.transmit = efi_net_transmit;
>>> + netobj->net.receive = efi_net_receive;
>>> + netobj->net.mode = &netobj->net_mode;
>>> + netobj->net_mode.state = EFI_NETWORK_STARTED;
>>> + netobj->dp[0] = dp_net;
>>> + netobj->dp[1] = dp_end;
>>> + memcpy(netobj->net_mode.current_address.mac_addr, eth_get_ethaddr(), 6);
>>> + netobj->net_mode.max_packet_size = PKTSIZE;
>>
>> Why is this statically created? Shouldn't it come from the U-Boot
>> ethernet tables dynamically when it is needed?
>
> The driver as is only exposes a single interface for the currently selected network device. My main goal behind this was pxe boot - where you usually load the payload from tftp and continue acting on the same interface later on.
>
> I guess we could create devices for all network devices as well. I remember that I wanted to only expose network if it's really necessary because of resource usage. But I don't remember exactly what resource the peoblem was otoh ;).
I think in general (given that you are writing this code and this is
the best opportunity to get the design right) that things like this
should look up U-Boot tables rather than creating their own. So a
model where the device is scanned as needed seems better. Then if we
want to change the constraints later, e.g. devices appear that were
not previously present, then we can deal with that.
I understand with block devices your point that there is no single
table of block devices. However, this support will be applied soon
(see u-boot-dm/master), even without driver model. I think we should
fix these things rather than work around them, as the code will be
more maintainable that way.
In this case I wonder if we should have an EFI device uclass, and
allow devices to have this as a child? It would allow for easy
enumeration and avoid another system-specific device table (something
that driver model is trying to reduce).
Regards,
Simon
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