According to the JEDEC standard the device length is communicated to an
OS as an exponent (power of two).

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
---
 hw/block/pflash_cfi01.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c
index 0cbc2fb4cb..8c9b3f518a 100644
--- a/hw/block/pflash_cfi01.c
+++ b/hw/block/pflash_cfi01.c
@@ -690,7 +690,7 @@ static const MemoryRegionOps pflash_cfi01_ops = {
     .endianness = DEVICE_NATIVE_ENDIAN,
 };
 
-static void pflash_cfi01_fill_cfi_table(PFlashCFI01 *pfl)
+static void pflash_cfi01_fill_cfi_table(PFlashCFI01 *pfl, Error **errp)
 {
     uint64_t blocks_per_device, sector_len_per_device, device_len;
     int num_devices;
@@ -708,6 +708,10 @@ static void pflash_cfi01_fill_cfi_table(PFlashCFI01 *pfl)
         sector_len_per_device = pfl->sector_len / num_devices;
     }
     device_len = sector_len_per_device * blocks_per_device;
+    if (ctpop64(device_len) != 1) {
+        error_setg(errp, "Device size must be a power of two.");
+        return;
+    }
 
     /* Hardcoded CFI table */
     /* Standard "QRY" string */
@@ -865,7 +869,7 @@ static void pflash_cfi01_realize(DeviceState *dev, Error **errp)
      */
     pfl->cmd = 0x00;
     pfl->status = 0x80; /* WSM ready */
-    pflash_cfi01_fill_cfi_table(pfl);
+    pflash_cfi01_fill_cfi_table(pfl, errp);
 }
 
 static void pflash_cfi01_system_reset(DeviceState *dev)
-- 
2.37.3

On Thu, Sep 15, 2022 at 11:26 PM Bernhard Beschow <shentey@gmail.com> wrote:
>
> According to the JEDEC standard the device length is communicated to an
> OS as an exponent (power of two).
>
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> ---
>  hw/block/pflash_cfi01.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>