Hi Ard/Leif/anyone who cares,
So I was trying to work out who broke MMC support in TC2 in the
upstream EDK2 tree. It was difficult because the tree is borked on
TC2 in so many interesting ways throughout history, but I eventually
bisected down to this patch:
300fc77 2015-08-25 ArmPlatformPkg/PL180MciDxe: check PrimeCell ID
before initializing [Ard Biesheuvel]
Basically, TC2 reads 0x02 for MCI_PERIPH_ID_REG3, when, according to
the spec, the register is supposed to read 0x00 in all cases. So the
driver doesn't probe and is never initialised. I guess this is an
FPGA bug in TC2? It's probably known about, but not to me ;-)
Anyway, how to fix it??
We could mask off the "stuck" bit, we could not check ID_REG3, there
are other things we could do.
I decided to mask off the bit rather than discard the register check
in my patch below, just to get things working
But would you like to do?
For extra point.... this was extra fun to track down due to other
problems. TC2 stopped booting since this patch was submitted
d340ef7 2014-08-26 ArmPkg/ArmArchTimerLib: Remove non required
[depex] and IoLib [Olivier Martin]
I've always carried a revert patch in my tree because I was previously
told I was wrong and that it wasn't a problem, even though it clearly
is. TC2 is spewing out a constant stream of this message:
IRQ Exception PC at 0xBFB74C20 CPSR 0x60000133
It wasn't fixed until Ard's patch that broke MMC support. Ugh!
I'm suspecting that the MMC support has a dependency on IoLib - for
that is the part of the patch that broke TC2 in the first place. But
I have yet to investigate that problem; I don't even know what IoLib
is.
So until this 2nd problem is fixed, I really don't want to submit a
fix to the PL180 problem or I'll have a dead TC2 port again :-/
Cheers,
Ryan.
---
ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.h | 3 +++
ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.c | 26 +++++++++++++++++++++++++-
2 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.h
b/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.h
index ce38a9e..8d36456 100644
--- a/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.h
+++ b/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.h
@@ -64,11 +64,14 @@
#define MCI_PERIPH_ID1 0x11
#define MCI_PERIPH_ID2 0x04
#define MCI_PERIPH_ID3 0x00
+#define MCI_PERIPH_ID3_TC2 0x02
#define MCI_PCELL_ID0 0x0D
#define MCI_PCELL_ID1 0xF0
#define MCI_PCELL_ID2 0x05
#define MCI_PCELL_ID3 0xB1
+#define MCI_PERIPH_ID3_MASK (~0x02)
+
#define MCI_POWER_OFF 0
#define MCI_POWER_UP BIT1
#define MCI_POWER_ON (BIT1 | BIT0)
diff --git a/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.c
b/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.c
index 688cd8a..8ae88b3 100644
--- a/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.c
+++ b/ArmPlatformPkg/Drivers/PL180MciDxe/PL180Mci.c
@@ -520,6 +520,14 @@ PL180MciDxeInitialize (
{
EFI_STATUS Status;
EFI_HANDLE Handle;
+ UINT8 r1 = MmioRead8 (MCI_PERIPH_ID_REG0);
+ UINT8 r2 = MmioRead8 (MCI_PERIPH_ID_REG1);
+ UINT8 r3 = MmioRead8 (MCI_PERIPH_ID_REG2);
+ UINT8 r4 = MmioRead8 (MCI_PERIPH_ID_REG3);
+ UINT8 r5 = MmioRead8 (MCI_PCELL_ID_REG0);
+ UINT8 r6 = MmioRead8 (MCI_PCELL_ID_REG1);
+ UINT8 r7 = MmioRead8 (MCI_PCELL_ID_REG2);
+ UINT8 r8 = MmioRead8 (MCI_PCELL_ID_REG3);
DEBUG ((EFI_D_WARN, "Probing ID registers at 0x%lx for a PL180\n",
MCI_PERIPH_ID_REG0));
@@ -528,14 +536,30 @@ PL180MciDxeInitialize (
if (MmioRead8 (MCI_PERIPH_ID_REG0) != MCI_PERIPH_ID0 ||
MmioRead8 (MCI_PERIPH_ID_REG1) != MCI_PERIPH_ID1 ||
MmioRead8 (MCI_PERIPH_ID_REG2) != MCI_PERIPH_ID2 ||
- MmioRead8 (MCI_PERIPH_ID_REG3) != MCI_PERIPH_ID3 ||
+ (MmioRead8 (MCI_PERIPH_ID_REG3) & MCI_PERIPH_ID3_MASK) !=
MCI_PERIPH_ID3 ||
MmioRead8 (MCI_PCELL_ID_REG0) != MCI_PCELL_ID0 ||
MmioRead8 (MCI_PCELL_ID_REG1) != MCI_PCELL_ID1 ||
MmioRead8 (MCI_PCELL_ID_REG2) != MCI_PCELL_ID2 ||
MmioRead8 (MCI_PCELL_ID_REG3) != MCI_PCELL_ID3) {
+ DEBUG ((EFI_D_ERROR, "PL180MciDxeInitialize(): Failed to probe PL180\n"));
+ DEBUG ((EFI_D_ERROR, "PL180MciDxeInitialize(): want:
%x,%x,%x,%x,%x,%x,%x,%x\n",
+ MCI_PERIPH_ID0,
+ MCI_PERIPH_ID1,
+ MCI_PERIPH_ID2,
+ MCI_PERIPH_ID3,
+ MCI_PCELL_ID0,
+ MCI_PCELL_ID1,
+ MCI_PCELL_ID2,
+ MCI_PCELL_ID3
+ ));
+
+ DEBUG ((EFI_D_ERROR, "PL180MciDxeInitialize(): read:
%x,%x,%x,%x,%x,%x,%x,%x\n", r1, r2, r3, r4, r5, r6, r7, r8));
return EFI_NOT_FOUND;
}
+ else {
+ DEBUG ((EFI_D_ERROR, "PL180MciDxeInitialize(): Probe succeeded\n"));
+ }
Handle = NULL;
--
2.5.0
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