drm/ast: Fixed system hanged if disable P2A

The original ast driver will access some BMC configuration through P2A bridge
that can be disabled since AST2300 and after.
It will cause system hanged if P2A bridge is disabled.
Here is the update to fix it.

Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 908011d2c8f5200e92cc8db772b85315d5c16343..7abda94fc2cf3bb43ec686ac4e699a43b77a11d0 100644 (file)
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -113,6 +113,7 @@ struct ast_private {
        struct ttm_bo_kmap_obj cache_kmap;
        int next_cursor;
        bool support_wide_screen;
+       bool DisableP2A;
 
        enum ast_tx_chip tx_chip_type;
        u8 dp501_maxclk;

diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index f75c6421db6239c9435ed39dc7d6244d13894920..533e762d036dc272afbdf4d2bce146b6f1b450d9 100644 (file)
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -124,6 +124,12 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post)
        } else
                *need_post = false;
 
+       /* Check P2A Access */
+       ast->DisableP2A = true;
+       data = ast_read32(ast, 0xf004);
+       if (data != 0xFFFFFFFF)
+               ast->DisableP2A = false;
+
        /* Check if we support wide screen */
        switch (ast->chip) {
        case AST1180:
@@ -140,15 +146,17 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post)
                        ast->support_wide_screen = true;
                else {
                        ast->support_wide_screen = false;
-                       /* Read SCU7c (silicon revision register) */
-                       ast_write32(ast, 0xf004, 0x1e6e0000);
-                       ast_write32(ast, 0xf000, 0x1);
-                       data = ast_read32(ast, 0x1207c);
-                       data &= 0x300;
-                       if (ast->chip == AST2300 && data == 0x0) /* ast1300 */
-                               ast->support_wide_screen = true;
-                       if (ast->chip == AST2400 && data == 0x100) /* ast1400 */
-                               ast->support_wide_screen = true;
+                       if (ast->DisableP2A == false) {
+                               /* Read SCU7c (silicon revision register) */
+                               ast_write32(ast, 0xf004, 0x1e6e0000);
+                               ast_write32(ast, 0xf000, 0x1);
+                               data = ast_read32(ast, 0x1207c);
+                               data &= 0x300;
+                               if (ast->chip == AST2300 && data == 0x0) /* ast1300 */
+                                       ast->support_wide_screen = true;
+                               if (ast->chip == AST2400 && data == 0x100) /* ast1400 */
+                                       ast->support_wide_screen = true;
+                       }
                }
                break;
        }
@@ -216,80 +224,81 @@ static int ast_get_dram_info(struct drm_device *dev)
        uint32_t data, data2;
        uint32_t denum, num, div, ref_pll;
 
-       ast_write32(ast, 0xf004, 0x1e6e0000);
-       ast_write32(ast, 0xf000, 0x1);
-
-
-       ast_write32(ast, 0x10000, 0xfc600309);
-
-       do {
-               if (pci_channel_offline(dev->pdev))
-                       return -EIO;
-       } while (ast_read32(ast, 0x10000) != 0x01);
-       data = ast_read32(ast, 0x10004);
-
-       if (data & 0x40)
+       if (ast->DisableP2A)
+       {
                ast->dram_bus_width = 16;
+               ast->dram_type = AST_DRAM_1Gx16;
+               ast->mclk = 396;
+       }
        else
-               ast->dram_bus_width = 32;
+       {
+               ast_write32(ast, 0xf004, 0x1e6e0000);
+               ast_write32(ast, 0xf000, 0x1);
+               data = ast_read32(ast, 0x10004);
+
+               if (data & 0x40)
+                       ast->dram_bus_width = 16;
+               else
+                       ast->dram_bus_width = 32;
+
+               if (ast->chip == AST2300 || ast->chip == AST2400) {
+                       switch (data & 0x03) {
+                       case 0:
+                               ast->dram_type = AST_DRAM_512Mx16;
+                               break;
+                       default:
+                       case 1:
+                               ast->dram_type = AST_DRAM_1Gx16;
+                               break;
+                       case 2:
+                               ast->dram_type = AST_DRAM_2Gx16;
+                               break;
+                       case 3:
+                               ast->dram_type = AST_DRAM_4Gx16;
+                               break;
+                       }
+               } else {
+                       switch (data & 0x0c) {
+                       case 0:
+                       case 4:
+                               ast->dram_type = AST_DRAM_512Mx16;
+                               break;
+                       case 8:
+                               if (data & 0x40)
+                                       ast->dram_type = AST_DRAM_1Gx16;
+                               else
+                                       ast->dram_type = AST_DRAM_512Mx32;
+                               break;
+                       case 0xc:
+                               ast->dram_type = AST_DRAM_1Gx32;
+                               break;
+                       }
+               }
 
-       if (ast->chip == AST2300 || ast->chip == AST2400) {
-               switch (data & 0x03) {
-               case 0:
-                       ast->dram_type = AST_DRAM_512Mx16;
-                       break;
-               default:
-               case 1:
-                       ast->dram_type = AST_DRAM_1Gx16;
-                       break;
-               case 2:
-                       ast->dram_type = AST_DRAM_2Gx16;
-                       break;
+               data = ast_read32(ast, 0x10120);
+               data2 = ast_read32(ast, 0x10170);
+               if (data2 & 0x2000)
+                       ref_pll = 14318;
+               else
+                       ref_pll = 12000;
+
+               denum = data & 0x1f;
+               num = (data & 0x3fe0) >> 5;
+               data = (data & 0xc000) >> 14;
+               switch (data) {
                case 3:
-                       ast->dram_type = AST_DRAM_4Gx16;
-                       break;
-               }
-       } else {
-               switch (data & 0x0c) {
-               case 0:
-               case 4:
-                       ast->dram_type = AST_DRAM_512Mx16;
+                       div = 0x4;
                        break;
-               case 8:
-                       if (data & 0x40)
-                               ast->dram_type = AST_DRAM_1Gx16;
-                       else
-                               ast->dram_type = AST_DRAM_512Mx32;
+               case 2:
+               case 1:
+                       div = 0x2;
                        break;
-               case 0xc:
-                       ast->dram_type = AST_DRAM_1Gx32;
+               default:
+                       div = 0x1;
                        break;
                }
+               ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div * 1000);
        }
-
-       data = ast_read32(ast, 0x10120);
-       data2 = ast_read32(ast, 0x10170);
-       if (data2 & 0x2000)
-               ref_pll = 14318;
-       else
-               ref_pll = 12000;
-
-       denum = data & 0x1f;
-       num = (data & 0x3fe0) >> 5;
-       data = (data & 0xc000) >> 14;
-       switch (data) {
-       case 3:
-               div = 0x4;
-               break;
-       case 2:
-       case 1:
-               div = 0x2;
-               break;
-       default:
-               div = 0x1;
-               break;
-       }
-       ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div * 1000);
        return 0;
 }
 

diff --git a/drivers/gpu/drm/ast/ast_post.c b/drivers/gpu/drm/ast/ast_post.c
index 810c51d92b99f81a441f37d02e319ed25b7768e5..5331ee1df086e7ae3950e33efc38975b544abdd4 100644 (file)
--- a/drivers/gpu/drm/ast/ast_post.c
+++ b/drivers/gpu/drm/ast/ast_post.c
@@ -379,12 +379,20 @@ void ast_post_gpu(struct drm_device *dev)
        ast_open_key(ast);
        ast_set_def_ext_reg(dev);
 
-       if (ast->chip == AST2300 || ast->chip == AST2400)
-               ast_init_dram_2300(dev);
-       else
-               ast_init_dram_reg(dev);
+       if (ast->DisableP2A == false)
+       {
+               if (ast->chip == AST2300 || ast->chip == AST2400)
+                       ast_init_dram_2300(dev);
+               else
+                       ast_init_dram_reg(dev);
 
-       ast_init_3rdtx(dev);
+               ast_init_3rdtx(dev);
+       }
+       else
+       {
+               if (ast->tx_chip_type != AST_TX_NONE)
+                       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa3, 0xcf, 0x80);        /* Enable DVO */
+       }
 }
 
 /* AST 2300 DRAM settings */