u-boot.git/common/memsize.c, branch v2026.07

common: memsize: fix occasionally failing alias probing

2026-05-04T18:58:47Z

probe_ram_size_by_alias() detects whether a probe address still aliases a lower address by writing through one address and reading through the other. On i.MX95 this occasionally reported a false non-alias when the alias read happened immediately after the write. A memory barrier alone, mb(), was tested but did not make the failure go away. This suggests that ordering the CPU accesses is not sufficient for this probe, likely because the issue is in the path to the memory controller rather than in the core itself. Read the written address back before checking the alias address. This appears to force the write to become observable at the probe address before using the alias read to decide whether the tested address range exists. If the readback does not match the written pattern, restore the saved value and continue with the next check. This keeps the probe robust for addresses that do not reliably retain the test pattern. Fixes: 0977448b45e2 ("common: memsize: add RAM size probe based on alias detection") Signed-off-by: Emanuele Ghidoli Reviewed-by: Simon Glass

common: memsize: add RAM size probe based on alias detection

2026-04-21T23:49:39Z

Add probe_ram_size_by_alias() to detect RAM size by checking whether a write to one address aliases to another address. Compared to get_ram_size(), this function allows the caller to: - limit probing to a small set of required accesses - avoid touching reserved or already used memory regions - handle non-linear alias patterns On the iMX95 SoC, when used with LPDDR5, accesses beyond the end of an 8GB DDR configuration do not alias to the expected linear wrap-around addresses. Instead, the aliased addresses appear to follow a pattern related to the DDRC bank and bank-group addresses mapping. Experimentally, the observed pattern is: Write Read y00000000 -> x0001c000 y00004000 -> x00018000 y00008000 -> x00014000 y0000c000 -> x00010000 y00010000 -> x0000c000 y00014000 -> x00008000 y00018000 -> x00004000 y0001c000 -> x00000000 This helper makes it possible to probe RAM size by explicitly specifying the probed address and the expected alias address for each size check. Signed-off-by: Emanuele Ghidoli Reviewed-by: Simon Glass

common/memsize.c: Fix get_ram_size() original data restore

2026-03-02T14:21:47Z

The get_ram_size() function fails to restore the original RAM data when the data cache is enabled. This issue was observed on an AM625 R5 SPL with 512MB of RAM and is a regression that became visible with commit bc07851897bd ("board: ti: Pull redundant DDR functions to a common location and Fixup DDR size when ECC is enabled"). Observed boot failure messages: Warning: Did not detect image signing certificate. Skipping authentication to prevent boot failure. This will fail on Security Enforcing(HS-SE) devices Authentication passed Starting ATF on ARM64 core... The system then hangs. This indicates that without a data cache flush, data in the cache is not coherent with RAM, preventing the system from booting. This was verified by printing the content of this address when the issue occurs. Add a data cache flush after each restore operation to resolve this issue. Fixes: bc07851897bd ("board: ti: Pull redundant DDR functions to a common location and Fixup DDR size when ECC is enabled") Fixes: 1c64b98c1ec4 ("common/memsize.c: Fix get_ram_size() when cache is enabled") Signed-off-by: Stefan Eichenberger Reviewed-by: Emanuele Ghidoli Tested-by: Francesco Dolcini # Toradex Verdin AM62

cache: Check dcache availability before calling cache functions

2025-09-30T06:29:55Z

When the data cache (dcache) is disabled, calling related status functions can lead to compilation errors due to undefined references. Adding a !CONFIG_IS_ENABLED(SYS_DCACHE_OFF) check before invoking dcache_status() (used in common/memsize.c:get_ram_size()) and mmu_status() (from arch/arm/include/asm/io.h). Without this check, builds with dcache disabled will fail to compile. Signed-off-by: Boon Khai Ng Reviewed-by: Tom Rini

Restore patch series "arm: dts: am62-beagleplay: Fix Beagleplay Ethernet"

2024-05-20T19:35:03Z

As part of bringing the master branch back in to next, we need to allow for all of these changes to exist here. Reported-by: Jonas Karlman Signed-off-by: Tom Rini

Revert "Merge patch series "arm: dts: am62-beagleplay: Fix Beagleplay Ethernet""

2024-05-19T14:16:36Z

When bringing in the series 'arm: dts: am62-beagleplay: Fix Beagleplay Ethernet"' I failed to notice that b4 noticed it was based on next and so took that as the base commit and merged that part of next to master. This reverts commit c8ffd1356d42223cbb8c86280a083cc3c93e6426, reversing changes made to 2ee6f3a5f7550de3599faef9704e166e5dcace35. Reported-by: Jonas Karlman Signed-off-by: Tom Rini

common: Remove and add needed includes

2024-05-06T21:05:04Z

Remove from all "commmon/" files and when needed add missing include files directly. Signed-off-by: Tom Rini

common/memsize.c: Fix get_ram_size() when cache is enabled

2023-06-21T20:54:25Z

Ensure that every write is flushed to memory and afterward reads are from memory. Since the algorithm rely on the fact that accessing to not existent memory lead to write at addr / 2 without this modification accesses to aliased (not physically present) addresses are cached and wrong size is returned. This was discovered while working on a TI AM625 based board where cache is normally enabled, see commit c02712a74849 ("arm: mach-k3: Enable dcache in SPL"). Signed-off-by: Emanuele Ghidoli Signed-off-by: Francesco Dolcini

Merge branch 'next'

2023-01-09T16:30:08Z

Signed-off-by: Tom Rini

common/memsize.c: Check for overflow in get_effective_memsize() only for mpc85xx

2023-01-07T23:01:53Z

This reverts commit 777aaaa706bc ("common/memsize.c: Fix get_effective_memsize() to check for overflow") for non-mpc85xx platforms. The changes to this generic function, which is intended to help with 32bit platforms with large amounts of memory has unintended side effects (which in turn lead to boot failures) on other platforms which were previously functional. For now do overflow check only for powerpc mpc85xx platform. It is needed to prevent crashing of P1/P2 boards with 4GB DDR module in 32-bit mode. Fixes: 777aaaa706bc ("common/memsize.c: Fix get_effective_memsize() to check for overflow") Signed-off-by: Pali Rohár