[PATCH] i3c: mipi-i3c-hci: Fix number of DAT/DCT entries for HCI versions < 1.1

Jarkko Nikula
2024-06-14T14:02:25Z

I was wrong about the TABLE_SIZE field description in the
commit 0676bfebf576 ("i3c: mipi-i3c-hci: Fix DAT/DCT entry sizes").

For the MIPI I3C HCI versions 1.0 and earlier the TABLE_SIZE field in
the registers DAT_SECTION_OFFSET and DCT_SECTION_OFFSET is indeed defined
in DWORDs and not number of entries like it is defined in later versions.

Where above fix allowed driver initialization to continue the wrongly
interpreted TABLE_SIZE field leads variables DAT_entries being twice and
DCT_entries four times as big as they really are.

That in turn leads clearing the DAT table over the boundary in the
dat_v1.c: hci_dat_v1_init().

So interprete the TABLE_SIZE field in DWORDs for HCI versions < 1.1 and
fix number of DAT/DCT entries accordingly.

Fixes: 0676bfebf576 ("i3c: mipi-i3c-hci: Fix DAT/DCT entry sizes")
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
---
drivers/i3c/master/mipi-i3c-hci/core.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
index faf723a0c739..0ff3055b8e78 100644
--- a/drivers/i3c/master/mipi-i3c-hci/core.c
+++ b/drivers/i3c/master/mipi-i3c-hci/core.c
@@ -646,6 +646,7 @@ static irqreturn_t i3c_hci_irq_handler(int irq, void *dev_id)
static int i3c_hci_init(struct i3c_hci *hci)
{
u32 regval, offset;
+ bool size_in_dwords;
int ret;

/* Validate HCI hardware version */
@@ -670,11 +671,16 @@ static int i3c_hci_init(struct i3c_hci *hci)
hci->caps = reg_read(HC_CAPABILITIES);
DBG("caps = %#x", hci->caps);

+ size_in_dwords = hci->version_major < 1 ||
+ (hci->version_major == 1 && hci->version_minor < 1);
+
regval = reg_read(DAT_SECTION);
offset = FIELD_GET(DAT_TABLE_OFFSET, regval);
hci->DAT_regs = offset ? hci->base_regs + offset : NULL;
hci->DAT_entries = FIELD_GET(DAT_TABLE_SIZE, regval);
hci->DAT_entry_size = FIELD_GET(DAT_ENTRY_SIZE, regval) ? 0 : 8;
+ if (size_in_dwords)
+ hci->DAT_entries = 4 * hci->DAT_entries / hci->DAT_entry_size;
dev_info(&hci->master.dev, "DAT: %u %u-bytes entries at offset %#x\n",
hci->DAT_entries, hci->DAT_entry_size, offset);

@@ -683,6 +689,8 @@ static int i3c_hci_init(struct i3c_hci *hci)
hci->DCT_regs = offset ? hci->base_regs + offset : NULL;
hci->DCT_entries = FIELD_GET(DCT_TABLE_SIZE, regval);
hci->DCT_entry_size = FIELD_GET(DCT_ENTRY_SIZE, regval) ? 0 : 16;
+ if (size_in_dwords)
+ hci->DCT_entries = 4 * hci->DCT_entries / hci->DCT_entry_size;
dev_info(&hci->master.dev, "DCT: %u %u-bytes entries at offset %#x\n",
hci->DCT_entries, hci->DCT_entry_size, offset);

--
2.43.0