Commit 22814751 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/ast: astdp: Perform link training during atomic_enable 



The place for link training is in the encoder's atomic_enable
helper. Remove all related tests from other helper ASTDP functions;
especially ast_astdp_is_connected(), which tests HPD status.

DP link training is controlled by the firmware. A status flag reports
success or failure. The process can be fragile on Aspeed hardware. Moving
the test from connector detection to the atomic_enable allows for several
retries and a longer timeout.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240717143319.104012-5-tzimmermann@suse.de
parent cbacb1b7

drivers/gpu/drm/ast/ast_dp.c

+22 −23
Original line number Diff line number Diff line
@@ -11,8 +11,6 @@ bool ast_astdp_is_connected(struct ast_device *ast) 
{

	if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, AST_IO_VGACRDF_HPD))

		return false;

	if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS))

		return false;

	return true;

}
@@ -22,14 +20,10 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata) 
	u8 i = 0, j = 0;



	/*

	 * CRDC[b0]: DP link success

	 * CRE5[b0]: Host reading EDID process is done

	 */

	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS) &&

		ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xE5,

								ASTDP_HOST_EDID_READ_DONE_MASK))) {

	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xE5, ASTDP_HOST_EDID_READ_DONE_MASK)))

		goto err_astdp_edid_not_ready;

	}



	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xE5, (u8) ~ASTDP_HOST_EDID_READ_DONE_MASK,

							0x00);
@@ -58,11 +52,6 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata) 
			 */

			mdelay(j+1);



			if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC,

							ASTDP_LINK_SUCCESS))) {

				goto err_astdp_jump_out_loop_of_edid;

			}



			j++;

			if (j > 200)

				goto err_astdp_jump_out_loop_of_edid;
@@ -106,8 +95,6 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata) 
	return (~(j+256) + 1);



err_astdp_edid_not_ready:

	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS)))

		return (~0xDC + 1);

	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xE5, ASTDP_HOST_EDID_READ_DONE_MASK)))

		return (~0xE5 + 1);
@@ -158,7 +145,22 @@ void ast_dp_power_on_off(struct drm_device *dev, bool on) 
	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xE3, (u8) ~AST_DP_PHY_SLEEP, bE3);

}



void ast_dp_link_training(struct ast_device *ast)

{

	struct drm_device *dev = &ast->base;

	unsigned int i = 10;



	while (i--) {

		u8 vgacrdc = ast_get_index_reg(ast, AST_IO_VGACRI, 0xdc);



		if (vgacrdc & AST_IO_VGACRDC_LINK_SUCCESS)

			break;

		if (i)

			msleep(100);

	}

	if (!i)

		drm_err(dev, "Link training failed\n");

}



void ast_dp_set_on_off(struct drm_device *dev, bool on)

{
@@ -169,8 +171,6 @@ void ast_dp_set_on_off(struct drm_device *dev, bool on) 
	// Video On/Off

	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xE3, (u8) ~AST_DP_VIDEO_ENABLE, on);



	// If DP plug in and link successful then check video on / off status

	if (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS)) {

	video_on_off <<= 4;

	while (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF,

						ASTDP_MIRROR_VIDEO_ENABLE) != video_on_off) {
@@ -180,7 +180,6 @@ void ast_dp_set_on_off(struct drm_device *dev, bool on) 
			break;

	}

}

}



void ast_dp_set_mode(struct drm_crtc *crtc, struct ast_vbios_mode_info *vbios_mode)

{

drivers/gpu/drm/ast/ast_drv.h

+1 −0
Original line number Diff line number Diff line
@@ -473,6 +473,7 @@ bool ast_astdp_is_connected(struct ast_device *ast); 
int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata);

int ast_dp_launch(struct ast_device *ast);

void ast_dp_power_on_off(struct drm_device *dev, bool no);

void ast_dp_link_training(struct ast_device *ast);

void ast_dp_set_on_off(struct drm_device *dev, bool no);

void ast_dp_set_mode(struct drm_crtc *crtc, struct ast_vbios_mode_info *vbios_mode);

drivers/gpu/drm/ast/ast_mode.c

+2 −0
Original line number Diff line number Diff line
@@ -1621,6 +1621,8 @@ static void ast_astdp_encoder_helper_atomic_enable(struct drm_encoder *encoder, 
	struct ast_device *ast = to_ast_device(dev);



	ast_dp_power_on_off(dev, AST_DP_POWER_ON);

	ast_dp_link_training(ast);



	ast_wait_for_vretrace(ast);

	ast_dp_set_on_off(dev, 1);

}

drivers/gpu/drm/ast/ast_reg.h

+1 −2
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ 
#define AST_IO_VGACRCB_HWC_ENABLED	BIT(1)



#define AST_IO_VGACRD1_MCU_FW_EXECUTING	BIT(5)

#define AST_IO_VGACRDC_LINK_SUCCESS	BIT(0)

#define AST_IO_VGACRDF_HPD		BIT(0)



#define AST_IO_VGAIR1_R			(0x5A)
@@ -70,10 +71,8 @@ 
#define AST_DP_VIDEO_ENABLE		BIT(0)



/*

 * CRDC[b0]: DP link success

 * CRE5[b0]: Host reading EDID process is done

 */

#define ASTDP_LINK_SUCCESS		BIT(0)

#define ASTDP_HOST_EDID_READ_DONE	BIT(0)

#define ASTDP_HOST_EDID_READ_DONE_MASK	GENMASK(0, 0)