Re: [PATCH 09/10] drm/i915/hdcp: migrate away from kdev_to_i915() in GSC messaging

[Jani Nikula <jani.nikula@intel.com>]

On Tue, 06 Aug 2024, Jani Nikula <jani.nikula@intel.com> wrote:
> On Thu, 01 Aug 2024, Gustavo Sousa <gustavo.sousa@intel.com> wrote:
>> Quoting Jani Nikula (2024-07-29 11:30:10-03:00)
>>>Use to_intel_display() instead of kdev_to_i915() in the HDCP component
>>>API hooks. Avoid further drive-by changes at this point, and just
>>>convert the display pointer to i915, and leave the struct intel_display
>>>conversion for later.
>>>
>>>The NULL error checking in the hooks make this a bit cumbersome. I'm not
>>>actually sure they're really required, but don't go down that rabbit
>>>hole just now.
>>>
>>>Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>>>---
>>> .../drm/i915/display/intel_hdcp_gsc_message.c | 67 +++++++++++++------
>>> 1 file changed, 45 insertions(+), 22 deletions(-)
>>>
>>>diff --git a/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c b/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>>index 6548e71b4c49..35bdb532bbb3 100644
>>>--- a/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>>+++ b/drivers/gpu/drm/i915/display/intel_hdcp_gsc_message.c
>>>@@ -7,6 +7,7 @@
>>> #include <drm/intel/i915_hdcp_interface.h>
>>> 
>>> #include "i915_drv.h"
>>>+#include "intel_display_types.h"
>>> #include "intel_hdcp_gsc_message.h"
>>> 
>>> int
>>>@@ -15,17 +16,19 @@ intel_hdcp_gsc_initiate_session(struct device *dev, struct hdcp_port_data *data,
>>> {
>>>         struct wired_cmd_initiate_hdcp2_session_in session_init_in = {};
>>>         struct wired_cmd_initiate_hdcp2_session_out session_init_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !ake_data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>
>> Hm... I'm afraid that wouldn't really work if drvdata was NULL, would
>> it?
>>
>> With a NULL drvdata, I believe we would probably get a non-zero offset
>> here.
>
> Right, good catch. Not sure I want to add that check to everything in
> to_intel_display() macro, because in most cases the passed in value
> can't be NULL. Driver data is a bit different, though I don't think it
> should really be NULL either.

Decided to fix this in __drm_device_to_intel_display() like this:

 #define __drm_device_to_intel_display(p) \
-       (&to_i915(p)->display)
+       ((p) ? &to_i915(p)->display : NULL)

That'll have to change anyway when we can no longer use struct
drm_i915_private when going from drm_device to intel_display.

BR,
Jani.

>
> BR,
> Jani.
>
>
>
>>
>> --
>> Gustavo Sousa
>>
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         session_init_in.header.api_version = HDCP_API_VERSION;
>>>         session_init_in.header.command_id = WIRED_INITIATE_HDCP2_SESSION;
>>>@@ -72,17 +75,19 @@ intel_hdcp_gsc_verify_receiver_cert_prepare_km(struct device *dev,
>>> {
>>>         struct wired_cmd_verify_receiver_cert_in verify_rxcert_in = {};
>>>         struct wired_cmd_verify_receiver_cert_out verify_rxcert_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         verify_rxcert_in.header.api_version = HDCP_API_VERSION;
>>>         verify_rxcert_in.header.command_id = WIRED_VERIFY_RECEIVER_CERT;
>>>@@ -135,17 +140,19 @@ intel_hdcp_gsc_verify_hprime(struct device *dev, struct hdcp_port_data *data,
>>> {
>>>         struct wired_cmd_ake_send_hprime_in send_hprime_in = {};
>>>         struct wired_cmd_ake_send_hprime_out send_hprime_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !rx_hprime)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         send_hprime_in.header.api_version = HDCP_API_VERSION;
>>>         send_hprime_in.header.command_id = WIRED_AKE_SEND_HPRIME;
>>>@@ -183,17 +190,19 @@ intel_hdcp_gsc_store_pairing_info(struct device *dev, struct hdcp_port_data *dat
>>> {
>>>         struct wired_cmd_ake_send_pairing_info_in pairing_info_in = {};
>>>         struct wired_cmd_ake_send_pairing_info_out pairing_info_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !pairing_info)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         pairing_info_in.header.api_version = HDCP_API_VERSION;
>>>         pairing_info_in.header.command_id = WIRED_AKE_SEND_PAIRING_INFO;
>>>@@ -234,17 +243,19 @@ intel_hdcp_gsc_initiate_locality_check(struct device *dev,
>>> {
>>>         struct wired_cmd_init_locality_check_in lc_init_in = {};
>>>         struct wired_cmd_init_locality_check_out lc_init_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !lc_init_data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         lc_init_in.header.api_version = HDCP_API_VERSION;
>>>         lc_init_in.header.command_id = WIRED_INIT_LOCALITY_CHECK;
>>>@@ -280,17 +291,19 @@ intel_hdcp_gsc_verify_lprime(struct device *dev, struct hdcp_port_data *data,
>>> {
>>>         struct wired_cmd_validate_locality_in verify_lprime_in = {};
>>>         struct wired_cmd_validate_locality_out verify_lprime_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !rx_lprime)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         verify_lprime_in.header.api_version = HDCP_API_VERSION;
>>>         verify_lprime_in.header.command_id = WIRED_VALIDATE_LOCALITY;
>>>@@ -330,17 +343,19 @@ int intel_hdcp_gsc_get_session_key(struct device *dev,
>>> {
>>>         struct wired_cmd_get_session_key_in get_skey_in = {};
>>>         struct wired_cmd_get_session_key_out get_skey_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data || !ske_data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         get_skey_in.header.api_version = HDCP_API_VERSION;
>>>         get_skey_in.header.command_id = WIRED_GET_SESSION_KEY;
>>>@@ -382,17 +397,19 @@ intel_hdcp_gsc_repeater_check_flow_prepare_ack(struct device *dev,
>>> {
>>>         struct wired_cmd_verify_repeater_in verify_repeater_in = {};
>>>         struct wired_cmd_verify_repeater_out verify_repeater_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !rep_topology || !rep_send_ack || !data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         verify_repeater_in.header.api_version = HDCP_API_VERSION;
>>>         verify_repeater_in.header.command_id = WIRED_VERIFY_REPEATER;
>>>@@ -442,6 +459,7 @@ int intel_hdcp_gsc_verify_mprime(struct device *dev,
>>> {
>>>         struct wired_cmd_repeater_auth_stream_req_in *verify_mprime_in;
>>>         struct wired_cmd_repeater_auth_stream_req_out verify_mprime_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>>         size_t cmd_size;
>>>@@ -449,11 +467,12 @@ int intel_hdcp_gsc_verify_mprime(struct device *dev,
>>>         if (!dev || !stream_ready || !data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         cmd_size = struct_size(verify_mprime_in, streams, data->k);
>>>         if (cmd_size == SIZE_MAX)
>>>@@ -504,17 +523,19 @@ int intel_hdcp_gsc_enable_authentication(struct device *dev,
>>> {
>>>         struct wired_cmd_enable_auth_in enable_auth_in = {};
>>>         struct wired_cmd_enable_auth_out enable_auth_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         enable_auth_in.header.api_version = HDCP_API_VERSION;
>>>         enable_auth_in.header.command_id = WIRED_ENABLE_AUTH;
>>>@@ -549,17 +570,19 @@ intel_hdcp_gsc_close_session(struct device *dev, struct hdcp_port_data *data)
>>> {
>>>         struct wired_cmd_close_session_in session_close_in = {};
>>>         struct wired_cmd_close_session_out session_close_out = {};
>>>+        struct intel_display *display;
>>>         struct drm_i915_private *i915;
>>>         ssize_t byte;
>>> 
>>>         if (!dev || !data)
>>>                 return -EINVAL;
>>> 
>>>-        i915 = kdev_to_i915(dev);
>>>-        if (!i915) {
>>>+        display = to_intel_display(dev);
>>>+        if (!display) {
>>>                 dev_err(dev, "DRM not initialized, aborting HDCP.\n");
>>>                 return -ENODEV;
>>>         }
>>>+        i915 = to_i915(display->drm);
>>> 
>>>         session_close_in.header.api_version = HDCP_API_VERSION;
>>>         session_close_in.header.command_id = WIRED_CLOSE_SESSION;
>>>-- 
>>>2.39.2
>>>

-- 
Jani Nikula, Intel