| Message ID | d0b4aa2e-8b5d-4c27-8aab-164a089d95bd@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] i2c: smbus: Prepare i2c_register_spd for usage on muxed segments | expand |
On 04.03.2024 08:46, Wolfram Sang wrote: > Hello Heiner, > Hello Wolfram, > >> + dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", >> + dimm_count, slot_count); > > I am still in favor of removing this. I don't like the inconsistency of > the printout depending on the bus being muxed or not. We still have one > printout per device instantiated. > > If you agree, I can remove this while applying. If not, then I'll apply > as is. No strong opinion here on my side. > Yes, please remove it. I'll submit a patch for adding this message to drivers/firmware/dmi_scan.c. Let's whether DMI maintainers find it useful. > Happy hacking, > > Wolfram > Heiner
On Sat, Mar 02, 2024 at 09:39:13PM +0100, Heiner Kallweit wrote: > If this is an adapter on a muxed bus segment, assume that each segment > is connected to a subset of the (> 8) overall memory slots. In this > case let's probe the maximum of 8 slots, however stop if the number > of overall populated slots is reached. > > If we're not on a muxed segment and the total number of slots is > 8, > then warn because then not all SPD eeproms can be addressed. > Presumably the bus is muxed, but the mux config is missing. > > Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Removed the printout and applied to for-next, thanks!
diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c index 74807c6db..c45d09782 100644 --- a/drivers/i2c/i2c-smbus.c +++ b/drivers/i2c/i2c-smbus.c @@ -351,13 +351,20 @@ void i2c_register_spd(struct i2c_adapter *adap) if (!dimm_count) return; - dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", - dimm_count, slot_count); - - if (slot_count > 8) { - dev_warn(&adap->dev, - "Systems with more than 8 memory slots not supported yet, not instantiating SPD\n"); - return; + /* + * If we're a child adapter on a muxed segment, then limit slots to 8, + * as this is the max number of SPD EEPROMs that can be addressed per bus. + */ + if (i2c_parent_is_i2c_adapter(adap)) { + slot_count = 8; + } else { + if (slot_count > 8) { + dev_warn(&adap->dev, + "More than 8 memory slots on a single bus, contact i801 maintainer to add missing mux config\n"); + return; + } + dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", + dimm_count, slot_count); } /*
If this is an adapter on a muxed bus segment, assume that each segment is connected to a subset of the (> 8) overall memory slots. In this case let's probe the maximum of 8 slots, however stop if the number of overall populated slots is reached. If we're not on a muxed segment and the total number of slots is > 8, then warn because then not all SPD eeproms can be addressed. Presumably the bus is muxed, but the mux config is missing. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- v2: - Make comments / messages more descriptive - Remove second patch of the series to ask for testing on lkml - change dev_err to dev_warn --- drivers/i2c/i2c-smbus.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-)