imx: add comments and remove unused struct fields
Add comment block for the imx_ddr_size function and remove the extra unused
fields from struct esd_mmdc_regs which are also not common between IMX53 and
IMX6.
Cc: Stefan Roese <sr@denx.de>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Andy Ng <andreas2025@gmail.com>
Cc: Eric Nelson <eric.nelson@boundarydevices.com>
Cc: Tapani Utriainen <tapani@technexion.com>
Cc: Tom Rini <trini@ti.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Acked-by: Stefano Babic <sbabic@denx.de>
Acked-by: Nikita Kiryanov <nikita@compulab.co.il>
diff --git a/arch/arm/imx-common/cpu.c b/arch/arm/imx-common/cpu.c
index a77c4de..5a09107 100644
--- a/arch/arm/imx-common/cpu.c
+++ b/arch/arm/imx-common/cpu.c
@@ -58,6 +58,7 @@
static const unsigned char col_lookup[] = {9, 10, 11, 8, 12, 9, 9, 9};
static const unsigned char bank_lookup[] = {3, 2};
+/* these MMDC registers are common to the IMX53 and IMX6 */
struct esd_mmdc_regs {
uint32_t ctl;
uint32_t pdc;
@@ -66,15 +67,6 @@
uint32_t cfg1;
uint32_t cfg2;
uint32_t misc;
- uint32_t scr;
- uint32_t ref;
- uint32_t rsvd1;
- uint32_t rsvd2;
- uint32_t rwd;
- uint32_t or;
- uint32_t mrr;
- uint32_t cfg3lp;
- uint32_t mr4;
};
#define ESD_MMDC_CTL_GET_ROW(mdctl) ((ctl >> 24) & 7)
@@ -83,6 +75,12 @@
#define ESD_MMDC_CTL_GET_CS1(mdctl) ((ctl >> 30) & 1)
#define ESD_MMDC_MISC_GET_BANK(mdmisc) ((misc >> 5) & 1)
+/*
+ * imx_ddr_size - return size in bytes of DRAM according MMDC config
+ * The MMDC MDCTL register holds the number of bits for row, col, and data
+ * width and the MMDC MDMISC register holds the number of banks. Combine
+ * all these bits to determine the meme size the MMDC has been configured for
+ */
unsigned imx_ddr_size(void)
{
struct esd_mmdc_regs *mem = (struct esd_mmdc_regs *)MEMCTL_BASE;