gxfb: add power management functionality

This adds the ability to suspend/resume the gxfb driver, which includes:
  - The addition of a Graphics Processor register table in gxfb.h, and
    associated GP handling.
  - Register and palette saving code; registers are stored in gxfb_par.
    A few MSR values are saved as well.
  - gx_powerup and gx_powerdown functions which restore/save registers and
    enable/disable graphic engines.
  - gxfb_suspend/gxfb_resume

Originally based on a patch by Jordan Crouse.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 71 insertions, 1 deletions

diff --git a/drivers/video/geode/gxfb.h b/drivers/video/geode/gxfb.h
index b8db7f82646c..16a96f8fd8c5 100644
--- a/drivers/video/geode/gxfb.h
+++ b/drivers/video/geode/gxfb.h
@@ -13,10 +13,34 @@
 
 #include <linux/io.h>
 
+#define GP_REG_COUNT   (0x50 / 4)
+#define DC_REG_COUNT   (0x90 / 4)
+#define VP_REG_COUNT   (0x138 / 8)
+#define FP_REG_COUNT   (0x68 / 8)
+
+#define DC_PAL_COUNT   0x104
+
 struct gxfb_par {
         int enable_crt;
         void __iomem *dc_regs;
         void __iomem *vid_regs;
+        void __iomem *gp_regs;
+#ifdef CONFIG_PM
+        int powered_down;
+
+        /* register state, for power management functionality */
+        struct {
+                uint64_t padsel;
+                uint64_t dotpll;
+        } msr;
+
+        uint32_t gp[GP_REG_COUNT];
+        uint32_t dc[DC_REG_COUNT];
+        uint64_t vp[VP_REG_COUNT];
+        uint64_t fp[FP_REG_COUNT];
+
+        uint32_t pal[DC_PAL_COUNT];
+#endif
 };
 
 unsigned int gx_frame_buffer_size(void);
@@ -29,6 +53,43 @@ void gx_set_dclk_frequency(struct fb_info *info);
 void gx_configure_display(struct fb_info *info);
 int gx_blank_display(struct fb_info *info, int blank_mode);
 
+#ifdef CONFIG_PM
+int gx_powerdown(struct fb_info *info);
+int gx_powerup(struct fb_info *info);
+#endif
+
+
+/* Graphics Processor registers (table 6-23 from the data book) */
+enum gp_registers {
+        GP_DST_OFFSET = 0,
+        GP_SRC_OFFSET,
+        GP_STRIDE,
+        GP_WID_HEIGHT,
+
+        GP_SRC_COLOR_FG,
+        GP_SRC_COLOR_BG,
+        GP_PAT_COLOR_0,
+        GP_PAT_COLOR_1,
+
+        GP_PAT_COLOR_2,
+        GP_PAT_COLOR_3,
+        GP_PAT_COLOR_4,
+        GP_PAT_COLOR_5,
+
+        GP_PAT_DATA_0,
+        GP_PAT_DATA_1,
+        GP_RASTER_MODE,
+        GP_VECTOR_MODE,
+
+        GP_BLT_MODE,
+        GP_BLT_STATUS,
+        GP_HST_SRC,
+        GP_BASE_OFFSET, /* 0x4c */
+};
+
+#define GP_BLT_STATUS_BLT_PENDING       (1 << 2)
+#define GP_BLT_STATUS_BLT_BUSY          (1 << 0)
+
 
 /* Display Controller registers (table 6-38 from the data book) */
 enum dc_registers {
@@ -238,6 +299,16 @@ enum fp_registers {
 
 /* register access functions */
 
+static inline uint32_t read_gp(struct gxfb_par *par, int reg)
+{
+        return readl(par->gp_regs + 4*reg);
+}
+
+static inline void write_gp(struct gxfb_par *par, int reg, uint32_t val)
+{
+        writel(val, par->gp_regs + 4*reg);
+}
+
 static inline uint32_t read_dc(struct gxfb_par *par, int reg)
 {
         return readl(par->dc_regs + 4*reg);
@@ -248,7 +319,6 @@ static inline void write_dc(struct gxfb_par *par, int reg, uint32_t val)
         writel(val, par->dc_regs + 4*reg);
 }
 
-
 static inline uint32_t read_vp(struct gxfb_par *par, int reg)
 {
         return readl(par->vid_regs + 8*reg);