OMAP2+: UART: Remove cpu checks for populating errata flags

Currently the errata is populated based on cpu checks this can
be removed and replaced with module version check of uart ip block.
MVR reg is provided within the uart reg map use the same
to populate the errata and thus now errata population and handling
can be managed within the driver itself.

Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 73 insertions, 10 deletions

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 0cdd359a128e..6affdd4bee62 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -355,14 +355,6 @@ void __init omap_serial_init_port(struct omap_board_data *bdata,
         omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
         omap_up.autosuspend_timeout = info->autosuspend_timeout;
 
-        /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */
-        if (!cpu_is_omap2420() && !cpu_is_ti816x())
-                omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS;
-
-        /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */
-        if (cpu_is_omap34xx() || cpu_is_omap3630())
-                omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE;
-
         pdata = &omap_up;
         pdata_size = sizeof(struct omap_uart_port_info);
 
diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h
index 9ff444469f3d..1a52725ffcf2 100644
--- a/arch/arm/plat-omap/include/plat/omap-serial.h
+++ b/arch/arm/plat-omap/include/plat/omap-serial.h
@@ -65,7 +65,6 @@ struct omap_uart_port_info {
         bool                    dma_enabled;    /* To specify DMA Mode */
         unsigned int            uartclk;        /* UART clock rate */
         upf_t                   flags;          /* UPF_* flags */
-        u32                     errata;
         unsigned int            dma_rx_buf_size;
         unsigned int            dma_rx_timeout;
         unsigned int            autosuspend_timeout;
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 0121486ac4fa..0555c964e713 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -44,6 +44,13 @@
 #include <plat/dmtimer.h>
 #include <plat/omap-serial.h>
 
+#define UART_BUILD_REVISION(x, y)       (((x) << 8) | (y))
+
+#define OMAP_UART_REV_42 0x0402
+#define OMAP_UART_REV_46 0x0406
+#define OMAP_UART_REV_52 0x0502
+#define OMAP_UART_REV_63 0x0603
+
 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
 
 /* SCR register bitmasks */
@@ -53,6 +60,17 @@
 #define OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT                6
 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK                 (0x3 << 6)
 
+/* MVR register bitmasks */
+#define OMAP_UART_MVR_SCHEME_SHIFT      30
+
+#define OMAP_UART_LEGACY_MVR_MAJ_MASK   0xf0
+#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT  4
+#define OMAP_UART_LEGACY_MVR_MIN_MASK   0x0f
+
+#define OMAP_UART_MVR_MAJ_MASK          0x700
+#define OMAP_UART_MVR_MAJ_SHIFT         8
+#define OMAP_UART_MVR_MIN_MASK          0x3f
+
 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
 
 /* Forward declaration of functions */
@@ -1346,6 +1364,59 @@ static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
         return;
 }
 
+static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
+{
+        u32 mvr, scheme;
+        u16 revision, major, minor;
+
+        mvr = serial_in(up, UART_OMAP_MVER);
+
+        /* Check revision register scheme */
+        scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
+
+        switch (scheme) {
+        case 0: /* Legacy Scheme: OMAP2/3 */
+                /* MINOR_REV[0:4], MAJOR_REV[4:7] */
+                major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
+                                        OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
+                minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
+                break;
+        case 1:
+                /* New Scheme: OMAP4+ */
+                /* MINOR_REV[0:5], MAJOR_REV[8:10] */
+                major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
+                                        OMAP_UART_MVR_MAJ_SHIFT;
+                minor = (mvr & OMAP_UART_MVR_MIN_MASK);
+                break;
+        default:
+                dev_warn(&up->pdev->dev,
+                        "Unknown %s revision, defaulting to highest\n",
+                        up->name);
+                /* highest possible revision */
+                major = 0xff;
+                minor = 0xff;
+        }
+
+        /* normalize revision for the driver */
+        revision = UART_BUILD_REVISION(major, minor);
+
+        switch (revision) {
+        case OMAP_UART_REV_46:
+                up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
+                                UART_ERRATA_i291_DMA_FORCEIDLE);
+                break;
+        case OMAP_UART_REV_52:
+                up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
+                                UART_ERRATA_i291_DMA_FORCEIDLE);
+                break;
+        case OMAP_UART_REV_63:
+                up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
+                break;
+        default:
+                break;
+        }
+}
+
 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
 {
         struct omap_uart_port_info *omap_up_info;
@@ -1443,7 +1514,6 @@ static int serial_omap_probe(struct platform_device *pdev)
                                                 "%d\n", DEFAULT_CLK_SPEED);
         }
         up->uart_dma.uart_base = mem->start;
-        up->errata = omap_up_info->errata;
 
         if (omap_up_info->dma_enabled) {
                 up->uart_dma.uart_dma_tx = dma_tx->start;
@@ -1473,6 +1543,8 @@ static int serial_omap_probe(struct platform_device *pdev)
         pm_runtime_enable(&pdev->dev);
         pm_runtime_get_sync(&pdev->dev);
 
+        omap_serial_fill_features_erratas(up);
+
         ui[up->port.line] = up;
         serial_omap_add_console_port(up);