From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from loongson.cn (loongson.cn [114.242.206.163])
 by mx.groups.io with SMTP id smtpd.web09.10093.1637833405933309252
 for <devel@edk2.groups.io>;
 Thu, 25 Nov 2021 01:43:26 -0800
Authentication-Results: mx.groups.io;
 dkim=missing; spf=pass (domain: loongson.cn, ip: 114.242.206.163, mailfrom: maobibo@loongson.cn)
Received: from [10.20.42.25] (unknown [10.20.42.25])
	by mail.loongson.cn (Coremail) with SMTP id AQAAf9Dx79O5Wp9hYFIBAA--.5841S3;
	Thu, 25 Nov 2021 17:43:21 +0800 (CST)
To: Gerd Hoffmann <kraxel@redhat.com>
Cc: devel@edk2.groups.io
From: maobibo@loongson.cn
Subject: one possible issue with ovmf fvb
Message-ID: <444f3f42-cc2c-f255-389e-504b31789fcd@loongson.cn>
Date: Thu, 25 Nov 2021 17:43:20 +0800
User-Agent: Mozilla/5.0 (X11; Linux mips64; rv:52.0) Gecko/20100101
 Thunderbird/52.9.1
MIME-Version: 1.0
X-CM-TRANSID: AQAAf9Dx79O5Wp9hYFIBAA--.5841S3
X-Coremail-Antispam: 1UD129KBjvJXoW7Cr4DXryDGw43Kry8AFWkZwb_yoW8Gr45pa
	nxXwsIq34UGFy8J34kX3s7Xr1kJ398Ga45G3sIgF1xJa15Zwnruw1UAa1fGFyqyrWjyF1j
	qr4UZF1kCrykGrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2
	9KBjDU0xBIdaVrnRJUUUvYb7Iv0xC_Kw4lb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I2
	0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw
	A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xII
	jxv20xvEc7CjxVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwV
	C2z280aVCY1x0267AKxVW0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC
	0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr
	1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcVAKI48JMxk0xIA0c2IEe2xFo4CEbIxvr21l
	c2xSY4AK6svPMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I
	8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUXVWU
	AwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x
	0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_WFyUJVCq3wCI42IY6I8E87Iv67AK
	xVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x07
	bOoGdUUUUU=
X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit

Hi Gerd,

  I am porting Loongarch Qemu uefi bios, and I want to use reuse ovmf code. And I encounter one problem
when using OvmfPkg/EmuVariableFvbRuntimeDxe/Fvb.c

  here is piece of code:
-----------------------------------------------------------
  Initialize = TRUE;
  if (PcdGet64 (PcdEmuVariableNvStoreReserved) != 0) {
    Ptr = (VOID*)(UINTN) PcdGet64 (PcdEmuVariableNvStoreReserved);
    DEBUG ((
      DEBUG_INFO,
      "EMU Variable FVB: Using pre-reserved block at %p\n",
      Ptr
      ));
    Status = ValidateFvHeader (Ptr);
    if (!EFI_ERROR (Status)) {
      DEBUG ((DEBUG_INFO, "EMU Variable FVB: Found valid pre-existing FV\n"));
      Initialize = FALSE;
    }
  } else {
    Ptr = AllocateRuntimePages (EFI_SIZE_TO_PAGES (EMU_FVB_SIZE));
  }

  mEmuVarsFvb.BufferPtr = Ptr;

  //
  // Initialize the main FV header and variable store header
  //
  if (Initialize) {
    SetMem (Ptr, EMU_FVB_SIZE, ERASED_UINT8);
    InitializeFvAndVariableStoreHeaders (Ptr);
  }
  PcdStatus = PcdSet64S (PcdFlashNvStorageVariableBase64, (UINT32)(UINTN) Ptr);
  ASSERT_RETURN_ERROR (PcdStatus);

On my tcg vm, Ptr will be 64-bit physical address if memory exceeds 4G, I do not know whether there is similar issue on x64 ovmf.
ditto for the following PcdFlashNvStorageFtwSpareBase/PcdFlashNvStorageFtwWorkingBase

Can uefi bios manage memory beyond 4G?


regards
bibo, mao