[POWERPC] fsl_lbc: implement few UPM routines

Freescale UPM can be used to adjust localbus timings or to generate
orbitrary, pre-programmed "patterns" on the external Localbus signals.
This patch implements few routines so drivers could work with UPMs in
safe and generic manner.

So far there is just one user of these routines: Freescale UPM NAND
driver.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

1 files changed, 88 insertions, 0 deletions

diff --git a/include/asm-powerpc/fsl_lbc.h b/include/asm-powerpc/fsl_lbc.h
index 13a3c28e1e10..303f5484c050 100644
--- a/include/asm-powerpc/fsl_lbc.h
+++ b/include/asm-powerpc/fsl_lbc.h
@@ -24,6 +24,8 @@
 #define __ASM_FSL_LBC_H
 
 #include <linux/types.h>
+#include <linux/spinlock.h>
+#include <asm/io.h>
 
 struct fsl_lbc_bank {
         __be32 br;             /**< Base Register  */
@@ -98,6 +100,11 @@ struct fsl_lbc_regs {
         __be32 mar;             /**< UPM Address Register */
         u8 res1[0x4];
         __be32 mamr;            /**< UPMA Mode Register */
+#define MxMR_OP_NO      (0 << 28) /**< normal operation */
+#define MxMR_OP_WA      (1 << 28) /**< write array */
+#define MxMR_OP_RA      (2 << 28) /**< read array */
+#define MxMR_OP_RP      (3 << 28) /**< run pattern */
+#define MxMR_MAD        0x3f      /**< machine address */
         __be32 mbmr;            /**< UPMB Mode Register */
         __be32 mcmr;            /**< UPMC Mode Register */
         u8 res2[0x8];
@@ -220,4 +227,85 @@ struct fsl_lbc_regs {
         u8 res8[0xF00];
 };
 
+extern struct fsl_lbc_regs __iomem *fsl_lbc_regs;
+extern spinlock_t fsl_lbc_lock;
+
+/*
+ * FSL UPM routines
+ */
+struct fsl_upm {
+        __be32 __iomem *mxmr;
+        int width;
+};
+
+extern int fsl_lbc_find(phys_addr_t addr_base);
+extern int fsl_upm_find(phys_addr_t addr_base, struct fsl_upm *upm);
+
+/**
+ * fsl_upm_start_pattern - start UPM patterns execution
+ * @upm:        pointer to the fsl_upm structure obtained via fsl_upm_find
+ * @pat_offset: UPM pattern offset for the command to be executed
+ *
+ * This routine programmes UPM so the next memory access that hits an UPM
+ * will trigger pattern execution, starting at pat_offset.
+ */
+static inline void fsl_upm_start_pattern(struct fsl_upm *upm, u8 pat_offset)
+{
+        clrsetbits_be32(upm->mxmr, MxMR_MAD, MxMR_OP_RP | pat_offset);
+}
+
+/**
+ * fsl_upm_end_pattern - end UPM patterns execution
+ * @upm:        pointer to the fsl_upm structure obtained via fsl_upm_find
+ *
+ * This routine reverts UPM to normal operation mode.
+ */
+static inline void fsl_upm_end_pattern(struct fsl_upm *upm)
+{
+        clrbits32(upm->mxmr, MxMR_OP_RP);
+
+        while (in_be32(upm->mxmr) & MxMR_OP_RP)
+                cpu_relax();
+}
+
+/**
+ * fsl_upm_run_pattern - actually run an UPM pattern
+ * @upm:        pointer to the fsl_upm structure obtained via fsl_upm_find
+ * @io_base:    remapped pointer to where memory access should happen
+ * @mar:        MAR register content during pattern execution
+ *
+ * This function triggers dummy write to the memory specified by the io_base,
+ * thus UPM pattern actually executed. Note that mar usage depends on the
+ * pre-programmed AMX bits in the UPM RAM.
+ */
+static inline int fsl_upm_run_pattern(struct fsl_upm *upm,
+                                      void __iomem *io_base, u32 mar)
+{
+        int ret = 0;
+        unsigned long flags;
+
+        spin_lock_irqsave(&fsl_lbc_lock, flags);
+
+        out_be32(&fsl_lbc_regs->mar, mar << (32 - upm->width));
+
+        switch (upm->width) {
+        case 8:
+                out_8(io_base, 0x0);
+                break;
+        case 16:
+                out_be16(io_base, 0x0);
+                break;
+        case 32:
+                out_be32(io_base, 0x0);
+                break;
+        default:
+                ret = -EINVAL;
+                break;
+        }
+
+        spin_unlock_irqrestore(&fsl_lbc_lock, flags);
+
+        return ret;
+}
+
 #endif /* __ASM_FSL_LBC_H */