Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
Not needed for qemu 1.7 (released in 2013) and newer.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
OvmfPkg/PlatformPei/MemDetect.c | 58 ++-------------------------------
1 file changed, 3 insertions(+), 55 deletions(-)
diff --git a/OvmfPkg/PlatformPei/MemDetect.c b/OvmfPkg/PlatformPei/MemDetect.c
index 20154255324b..8d2c7f432472 100644
--- a/OvmfPkg/PlatformPei/MemDetect.c
+++ b/OvmfPkg/PlatformPei/MemDetect.c
@@ -37,7 +37,6 @@ Module Name:
#include <Library/QemuFwCfgSimpleParserLib.h>
#include "Platform.h"
-#include "Cmos.h"
UINT8 mPhysMemAddressWidth;
@@ -295,52 +294,11 @@ GetSystemMemorySizeBelow4gb (
{
EFI_STATUS Status;
UINT64 LowerMemorySize = 0;
- UINT8 Cmos0x34;
- UINT8 Cmos0x35;
Status = ScanOrAdd64BitE820Ram (FALSE, &LowerMemorySize, NULL);
- if (Status == EFI_SUCCESS && LowerMemorySize > 0) {
- return LowerMemorySize;
- }
+ ASSERT (Status == EFI_SUCCESS && LowerMemorySize > 0);
+ return LowerMemorySize;
- //
- // CMOS 0x34/0x35 specifies the system memory above 16 MB.
- // * CMOS(0x35) is the high byte
- // * CMOS(0x34) is the low byte
- // * The size is specified in 64kb chunks
- // * Since this is memory above 16MB, the 16MB must be added
- // into the calculation to get the total memory size.
- //
-
- Cmos0x34 = (UINT8) CmosRead8 (0x34);
- Cmos0x35 = (UINT8) CmosRead8 (0x35);
-
- return (UINT32) (((UINTN)((Cmos0x35 << 8) + Cmos0x34) << 16) + SIZE_16MB);
-}
-
-
-STATIC
-UINT64
-GetSystemMemorySizeAbove4gb (
- )
-{
- UINT32 Size;
- UINTN CmosIndex;
-
- //
- // CMOS 0x5b-0x5d specifies the system memory above 4GB MB.
- // * CMOS(0x5d) is the most significant size byte
- // * CMOS(0x5c) is the middle size byte
- // * CMOS(0x5b) is the least significant size byte
- // * The size is specified in 64kb chunks
- //
-
- Size = 0;
- for (CmosIndex = 0x5d; CmosIndex >= 0x5b; CmosIndex--) {
- Size = (UINT32) (Size << 8) + (UINT32) CmosRead8 (CmosIndex);
- }
-
- return LShiftU64 (Size, 16);
}
@@ -371,12 +329,9 @@ GetFirstNonAddress (
// If QEMU presents an E820 map, then get the highest exclusive >=4GB RAM
// address from it. This can express an address >= 4GB+1TB.
//
- // Otherwise, get the flat size of the memory above 4GB from the CMOS (which
- // can only express a size smaller than 1TB), and add it to 4GB.
- //
Status = ScanOrAdd64BitE820Ram (FALSE, NULL, &FirstNonAddress);
if (EFI_ERROR (Status)) {
- FirstNonAddress = BASE_4GB + GetSystemMemorySizeAbove4gb ();
+ FirstNonAddress = BASE_4GB;
}
//
@@ -719,7 +674,6 @@ QemuInitializeRam (
)
{
UINT64 LowerMemorySize;
- UINT64 UpperMemorySize;
MTRR_SETTINGS MtrrSettings;
EFI_STATUS Status;
@@ -775,12 +729,6 @@ QemuInitializeRam (
// memory size read from the CMOS.
//
Status = ScanOrAdd64BitE820Ram (TRUE, NULL, NULL);
- if (EFI_ERROR (Status)) {
- UpperMemorySize = GetSystemMemorySizeAbove4gb ();
- if (UpperMemorySize != 0) {
- AddMemoryBaseSizeHob (BASE_4GB, UpperMemorySize);
- }
- }
}
//
--
2.31.1
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On Thu, 26 Aug 2021 at 11:55, Gerd Hoffmann <kraxel@redhat.com> wrote:
>
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
>
> Not needed for qemu 1.7 (released in 2013) and newer.
>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
> OvmfPkg/PlatformPei/MemDetect.c | 58 ++-------------------------------
> 1 file changed, 3 insertions(+), 55 deletions(-)
>
> diff --git a/OvmfPkg/PlatformPei/MemDetect.c b/OvmfPkg/PlatformPei/MemDetect.c
> index 20154255324b..8d2c7f432472 100644
> --- a/OvmfPkg/PlatformPei/MemDetect.c
> +++ b/OvmfPkg/PlatformPei/MemDetect.c
> @@ -37,7 +37,6 @@ Module Name:
> #include <Library/QemuFwCfgSimpleParserLib.h>
>
> #include "Platform.h"
> -#include "Cmos.h"
>
> UINT8 mPhysMemAddressWidth;
>
> @@ -295,52 +294,11 @@ GetSystemMemorySizeBelow4gb (
> {
> EFI_STATUS Status;
> UINT64 LowerMemorySize = 0;
> - UINT8 Cmos0x34;
> - UINT8 Cmos0x35;
>
> Status = ScanOrAdd64BitE820Ram (FALSE, &LowerMemorySize, NULL);
> - if (Status == EFI_SUCCESS && LowerMemorySize > 0) {
> - return LowerMemorySize;
> - }
> + ASSERT (Status == EFI_SUCCESS && LowerMemorySize > 0);
Nit: better to do
ASSERT_EFI_ERROR (Status);
ASSERT (LowerMemorySize > 0);
so that you can tell from the debug log which condition triggered, and
if it is the first one, what the actual error code was.
> + return LowerMemorySize;
>
> - //
> - // CMOS 0x34/0x35 specifies the system memory above 16 MB.
> - // * CMOS(0x35) is the high byte
> - // * CMOS(0x34) is the low byte
> - // * The size is specified in 64kb chunks
> - // * Since this is memory above 16MB, the 16MB must be added
> - // into the calculation to get the total memory size.
> - //
> -
> - Cmos0x34 = (UINT8) CmosRead8 (0x34);
> - Cmos0x35 = (UINT8) CmosRead8 (0x35);
> -
> - return (UINT32) (((UINTN)((Cmos0x35 << 8) + Cmos0x34) << 16) + SIZE_16MB);
> -}
> -
> -
> -STATIC
> -UINT64
> -GetSystemMemorySizeAbove4gb (
> - )
> -{
> - UINT32 Size;
> - UINTN CmosIndex;
> -
> - //
> - // CMOS 0x5b-0x5d specifies the system memory above 4GB MB.
> - // * CMOS(0x5d) is the most significant size byte
> - // * CMOS(0x5c) is the middle size byte
> - // * CMOS(0x5b) is the least significant size byte
> - // * The size is specified in 64kb chunks
> - //
> -
> - Size = 0;
> - for (CmosIndex = 0x5d; CmosIndex >= 0x5b; CmosIndex--) {
> - Size = (UINT32) (Size << 8) + (UINT32) CmosRead8 (CmosIndex);
> - }
> -
> - return LShiftU64 (Size, 16);
> }
>
>
> @@ -371,12 +329,9 @@ GetFirstNonAddress (
> // If QEMU presents an E820 map, then get the highest exclusive >=4GB RAM
> // address from it. This can express an address >= 4GB+1TB.
> //
> - // Otherwise, get the flat size of the memory above 4GB from the CMOS (which
> - // can only express a size smaller than 1TB), and add it to 4GB.
> - //
> Status = ScanOrAdd64BitE820Ram (FALSE, NULL, &FirstNonAddress);
> if (EFI_ERROR (Status)) {
> - FirstNonAddress = BASE_4GB + GetSystemMemorySizeAbove4gb ();
> + FirstNonAddress = BASE_4GB;
> }
>
> //
> @@ -719,7 +674,6 @@ QemuInitializeRam (
> )
> {
> UINT64 LowerMemorySize;
> - UINT64 UpperMemorySize;
> MTRR_SETTINGS MtrrSettings;
> EFI_STATUS Status;
>
> @@ -775,12 +729,6 @@ QemuInitializeRam (
> // memory size read from the CMOS.
> //
> Status = ScanOrAdd64BitE820Ram (TRUE, NULL, NULL);
> - if (EFI_ERROR (Status)) {
> - UpperMemorySize = GetSystemMemorySizeAbove4gb ();
> - if (UpperMemorySize != 0) {
> - AddMemoryBaseSizeHob (BASE_4GB, UpperMemorySize);
> - }
> - }
> }
>
> //
> --
> 2.31.1
>
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Good idea, Ard.
> ASSERT_EFI_ERROR (Status);
> ASSERT (LowerMemorySize > 0);
I like this suggestion.
Thank you
Yao Jiewen
> -----Original Message-----
> From: Ard Biesheuvel <ardb@kernel.org>
> Sent: Thursday, August 26, 2021 7:15 PM
> To: Gerd Hoffmann <kraxel@redhat.com>
> Cc: edk2-devel-groups-io <devel@edk2.groups.io>; Ard Biesheuvel
> <ardb+tianocore@kernel.org>; Yao, Jiewen <jiewen.yao@intel.com>; Justen,
> Jordan L <jordan.l.justen@intel.com>; Philippe Mathieu-Daude
> <philmd@redhat.com>
> Subject: Re: [PATCH v2 3/3] RFC: OvmfPkg/PlatformPei: stop using cmos for
> memory detection
>
> On Thu, 26 Aug 2021 at 11:55, Gerd Hoffmann <kraxel@redhat.com> wrote:
> >
> > Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
> >
> > Not needed for qemu 1.7 (released in 2013) and newer.
> >
> > Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> > ---
> > OvmfPkg/PlatformPei/MemDetect.c | 58 ++-------------------------------
> > 1 file changed, 3 insertions(+), 55 deletions(-)
> >
> > diff --git a/OvmfPkg/PlatformPei/MemDetect.c
> b/OvmfPkg/PlatformPei/MemDetect.c
> > index 20154255324b..8d2c7f432472 100644
> > --- a/OvmfPkg/PlatformPei/MemDetect.c
> > +++ b/OvmfPkg/PlatformPei/MemDetect.c
> > @@ -37,7 +37,6 @@ Module Name:
> > #include <Library/QemuFwCfgSimpleParserLib.h>
> >
> > #include "Platform.h"
> > -#include "Cmos.h"
> >
> > UINT8 mPhysMemAddressWidth;
> >
> > @@ -295,52 +294,11 @@ GetSystemMemorySizeBelow4gb (
> > {
> > EFI_STATUS Status;
> > UINT64 LowerMemorySize = 0;
> > - UINT8 Cmos0x34;
> > - UINT8 Cmos0x35;
> >
> > Status = ScanOrAdd64BitE820Ram (FALSE, &LowerMemorySize, NULL);
> > - if (Status == EFI_SUCCESS && LowerMemorySize > 0) {
> > - return LowerMemorySize;
> > - }
> > + ASSERT (Status == EFI_SUCCESS && LowerMemorySize > 0);
>
> Nit: better to do
>
> ASSERT_EFI_ERROR (Status);
> ASSERT (LowerMemorySize > 0);
>
> so that you can tell from the debug log which condition triggered, and
> if it is the first one, what the actual error code was.
>
>
> > + return LowerMemorySize;
> >
> > - //
> > - // CMOS 0x34/0x35 specifies the system memory above 16 MB.
> > - // * CMOS(0x35) is the high byte
> > - // * CMOS(0x34) is the low byte
> > - // * The size is specified in 64kb chunks
> > - // * Since this is memory above 16MB, the 16MB must be added
> > - // into the calculation to get the total memory size.
> > - //
> > -
> > - Cmos0x34 = (UINT8) CmosRead8 (0x34);
> > - Cmos0x35 = (UINT8) CmosRead8 (0x35);
> > -
> > - return (UINT32) (((UINTN)((Cmos0x35 << 8) + Cmos0x34) << 16) +
> SIZE_16MB);
> > -}
> > -
> > -
> > -STATIC
> > -UINT64
> > -GetSystemMemorySizeAbove4gb (
> > - )
> > -{
> > - UINT32 Size;
> > - UINTN CmosIndex;
> > -
> > - //
> > - // CMOS 0x5b-0x5d specifies the system memory above 4GB MB.
> > - // * CMOS(0x5d) is the most significant size byte
> > - // * CMOS(0x5c) is the middle size byte
> > - // * CMOS(0x5b) is the least significant size byte
> > - // * The size is specified in 64kb chunks
> > - //
> > -
> > - Size = 0;
> > - for (CmosIndex = 0x5d; CmosIndex >= 0x5b; CmosIndex--) {
> > - Size = (UINT32) (Size << 8) + (UINT32) CmosRead8 (CmosIndex);
> > - }
> > -
> > - return LShiftU64 (Size, 16);
> > }
> >
> >
> > @@ -371,12 +329,9 @@ GetFirstNonAddress (
> > // If QEMU presents an E820 map, then get the highest exclusive >=4GB RAM
> > // address from it. This can express an address >= 4GB+1TB.
> > //
> > - // Otherwise, get the flat size of the memory above 4GB from the CMOS
> (which
> > - // can only express a size smaller than 1TB), and add it to 4GB.
> > - //
> > Status = ScanOrAdd64BitE820Ram (FALSE, NULL, &FirstNonAddress);
> > if (EFI_ERROR (Status)) {
> > - FirstNonAddress = BASE_4GB + GetSystemMemorySizeAbove4gb ();
> > + FirstNonAddress = BASE_4GB;
> > }
> >
> > //
> > @@ -719,7 +674,6 @@ QemuInitializeRam (
> > )
> > {
> > UINT64 LowerMemorySize;
> > - UINT64 UpperMemorySize;
> > MTRR_SETTINGS MtrrSettings;
> > EFI_STATUS Status;
> >
> > @@ -775,12 +729,6 @@ QemuInitializeRam (
> > // memory size read from the CMOS.
> > //
> > Status = ScanOrAdd64BitE820Ram (TRUE, NULL, NULL);
> > - if (EFI_ERROR (Status)) {
> > - UpperMemorySize = GetSystemMemorySizeAbove4gb ();
> > - if (UpperMemorySize != 0) {
> > - AddMemoryBaseSizeHob (BASE_4GB, UpperMemorySize);
> > - }
> > - }
> > }
> >
> > //
> > --
> > 2.31.1
> >
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