[PATCH v3 5/5] drm/msm/dp: Allow sub-regions to be specified in DT

From: Bjorn Andersson
Date: Fri Oct 01 2021 - 13:42:35 EST


Not all platforms has P0 at an offset of 0x1000 from the base address,
so add support for specifying each sub-region in DT. The code falls back
to the predefined offsets in the case that only a single reg is
specified, in order to support existing DT.

Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Reviewed-by: Abhinav Kumar <abhinavk@xxxxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---

Changes since v2:
- None

drivers/gpu/drm/msm/dp/dp_parser.c | 49 +++++++++++++++++++++++-------
1 file changed, 38 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c b/drivers/gpu/drm/msm/dp/dp_parser.c
index 1f084b2b5bd3..4d6e047f803d 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.c
+++ b/drivers/gpu/drm/msm/dp/dp_parser.c
@@ -50,18 +50,45 @@ static int dp_parser_ctrl_res(struct dp_parser *parser)
if (IS_ERR(dss->ahb.base))
return PTR_ERR(dss->ahb.base);

- if (dss->ahb.len < DP_DEFAULT_P0_OFFSET + DP_DEFAULT_P0_SIZE) {
- DRM_ERROR("legacy memory region not large enough\n");
- return -EINVAL;
- }
+ dss->aux.base = dp_ioremap(pdev, 1, &dss->aux.len);
+ if (IS_ERR(dss->aux.base)) {
+ /*
+ * The initial binding had a single reg, but in order to
+ * support variation in the sub-region sizes this was split.
+ * dp_ioremap() will fail with -ENODEV here if only a single
+ * reg is specified, so fill in the sub-region offsets and
+ * lengths based on this single region.
+ */
+ if (PTR_ERR(dss->aux.base) == -ENODEV) {
+ if (dss->ahb.len < DP_DEFAULT_P0_OFFSET + DP_DEFAULT_P0_SIZE) {
+ DRM_ERROR("legacy memory region not large enough\n");
+ return -EINVAL;
+ }
+
+ dss->ahb.len = DP_DEFAULT_AHB_SIZE;
+ dss->aux.base = dss->ahb.base + DP_DEFAULT_AUX_OFFSET;
+ dss->aux.len = DP_DEFAULT_AUX_SIZE;
+ dss->link.base = dss->ahb.base + DP_DEFAULT_LINK_OFFSET;
+ dss->link.len = DP_DEFAULT_LINK_SIZE;
+ dss->p0.base = dss->ahb.base + DP_DEFAULT_P0_OFFSET;
+ dss->p0.len = DP_DEFAULT_P0_SIZE;
+ } else {
+ DRM_ERROR("unable to remap aux region: %pe\n", dss->aux.base);
+ return PTR_ERR(dss->aux.base);
+ }
+ } else {
+ dss->link.base = dp_ioremap(pdev, 2, &dss->link.len);
+ if (IS_ERR(dss->link.base)) {
+ DRM_ERROR("unable to remap link region: %pe\n", dss->link.base);
+ return PTR_ERR(dss->link.base);
+ }

- dss->ahb.len = DP_DEFAULT_AHB_SIZE;
- dss->aux.base = dss->ahb.base + DP_DEFAULT_AUX_OFFSET;
- dss->aux.len = DP_DEFAULT_AUX_SIZE;
- dss->link.base = dss->ahb.base + DP_DEFAULT_LINK_OFFSET;
- dss->link.len = DP_DEFAULT_LINK_SIZE;
- dss->p0.base = dss->ahb.base + DP_DEFAULT_P0_OFFSET;
- dss->p0.len = DP_DEFAULT_P0_SIZE;
+ dss->p0.base = dp_ioremap(pdev, 3, &dss->p0.len);
+ if (IS_ERR(dss->p0.base)) {
+ DRM_ERROR("unable to remap p0 region: %pe\n", dss->p0.base);
+ return PTR_ERR(dss->p0.base);
+ }
+ }

io->phy = devm_phy_get(&pdev->dev, "dp");
if (IS_ERR(io->phy))
--
2.29.2