This function will shortly be used to help find if there is a route to a
device, serving an HPA, under a particular fixed memory window. Rather
than having that new use case subtract the base address in the caller,
only to add it again in cxl_cfmws_find_device(), push the responsibility
for calculating the HPA to the caller.

This also reduces the inconsistency in the meaning of the hwaddr
addr parameter between this function and the calls made within it
that access the HDM decoders that operating on HPA.

Signed-off-by: Alireza Sanaee <alireza.sanaee@huawei.com>
Tested-by: Gregory Price <gourry@gourry.net>
---
 hw/cxl/cxl-host.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
index f3479b1991..415a792380 100644
--- a/hw/cxl/cxl-host.c
+++ b/hw/cxl/cxl-host.c
@@ -157,7 +157,8 @@ static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
     return found;
 }
 
-static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
+static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr,
+                                        bool allow_interleave)
 {
     CXLComponentState *hb_cstate, *usp_cstate;
     PCIHostState *hb;
@@ -168,8 +169,6 @@ static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
     bool target_found;
     PCIDevice *rp, *d;
 
-    /* Address is relative to memory region. Convert to HPA */
-    addr += fw->base;
 
     rb_index = (addr / cxl_decode_ig(fw->enc_int_gran)) % fw->num_targets;
     hb = PCI_HOST_BRIDGE(fw->target_hbs[rb_index]->cxl_host_bridge);
@@ -254,7 +253,7 @@ static MemTxResult cxl_read_cfmws(void *opaque, hwaddr addr, uint64_t *data,
     CXLFixedWindow *fw = opaque;
     PCIDevice *d;
 
-    d = cxl_cfmws_find_device(fw, addr);
+    d = cxl_cfmws_find_device(fw, addr + fw->base, true);
     if (d == NULL) {
         *data = 0;
         /* Reads to invalid address return poison */
@@ -271,7 +270,7 @@ static MemTxResult cxl_write_cfmws(void *opaque, hwaddr addr,
     CXLFixedWindow *fw = opaque;
     PCIDevice *d;
 
-    d = cxl_cfmws_find_device(fw, addr);
+    d = cxl_cfmws_find_device(fw, addr + fw->base, true);
     if (d == NULL) {
         /* Writes to invalid address are silent */
         return MEMTX_OK;
-- 
2.43.0

On Mon, 16 Feb 2026 14:52:17 +0000
Alireza Sanaee <alireza.sanaee@huawei.com> wrote:

> This function will shortly be used to help find if there is a route to a
> device, serving an HPA, under a particular fixed memory window. Rather
> than having that new use case subtract the base address in the caller,
> only to add it again in cxl_cfmws_find_device(), push the responsibility
> for calculating the HPA to the caller.
> 
> This also reduces the inconsistency in the meaning of the hwaddr
> addr parameter between this function and the calls made within it
> that access the HDM decoders that operating on HPA.
> 
> Signed-off-by: Alireza Sanaee <alireza.sanaee@huawei.com>
> Tested-by: Gregory Price <gourry@gourry.net>
> ---
>  hw/cxl/cxl-host.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
> index f3479b1991..415a792380 100644
> --- a/hw/cxl/cxl-host.c
> +++ b/hw/cxl/cxl-host.c
> @@ -157,7 +157,8 @@ static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
>      return found;
>  }
>  
> -static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
> +static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr,
> +                                        bool allow_interleave)

This is doing two things and only one is the mentioned change.
The allow_interleave parameter should be in patch 2.

It'll be a little churn heavy as we'll change a couple of lines twice,
but it won't add an unused parameter and leave us with a harder to
review pair of patches.

Fix that up and you can add
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>

Jonathan



>  {
>      CXLComponentState *hb_cstate, *usp_cstate;
>      PCIHostState *hb;
> @@ -168,8 +169,6 @@ static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
>      bool target_found;
>      PCIDevice *rp, *d;
>  
> -    /* Address is relative to memory region. Convert to HPA */
> -    addr += fw->base;
>  
>      rb_index = (addr / cxl_decode_ig(fw->enc_int_gran)) % fw->num_targets;
>      hb = PCI_HOST_BRIDGE(fw->target_hbs[rb_index]->cxl_host_bridge);
> @@ -254,7 +253,7 @@ static MemTxResult cxl_read_cfmws(void *opaque, hwaddr addr, uint64_t *data,
>      CXLFixedWindow *fw = opaque;
>      PCIDevice *d;
>  
> -    d = cxl_cfmws_find_device(fw, addr);
> +    d = cxl_cfmws_find_device(fw, addr + fw->base, true);
>      if (d == NULL) {
>          *data = 0;
>          /* Reads to invalid address return poison */
> @@ -271,7 +270,7 @@ static MemTxResult cxl_write_cfmws(void *opaque, hwaddr addr,
>      CXLFixedWindow *fw = opaque;
>      PCIDevice *d;
>  
> -    d = cxl_cfmws_find_device(fw, addr);
> +    d = cxl_cfmws_find_device(fw, addr + fw->base, true);
>      if (d == NULL) {
>          /* Writes to invalid address are silent */
>          return MEMTX_OK;