[PATCH 19/29] memstick: jmb38x_ms: add register read/write functions
From: Maxim Levitsky
Date: Fri Oct 22 2010 - 19:57:33 EST
All over the code it is a bit easier to see the
register access with this patch. Also set/clear mask
helpers refactor code a bit, but the biggest reason
for this patch is to make it possible to trace register
read/writes with a flip of a module param.
Currently these functions are unused, but will be by later code
Signed-off-by: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
---
drivers/memstick/host/jmb38x_ms.c | 102 ++++++++++++++++++++++++++++++++++++-
drivers/memstick/host/jmb38x_ms.h | 1 +
2 files changed, 102 insertions(+), 1 deletions(-)
diff --git a/drivers/memstick/host/jmb38x_ms.c b/drivers/memstick/host/jmb38x_ms.c
index 295f755..bcdb785 100644
--- a/drivers/memstick/host/jmb38x_ms.c
+++ b/drivers/memstick/host/jmb38x_ms.c
@@ -22,8 +22,86 @@
static int no_dma;
static int debug;
+/* Read a register*/
+static inline u32 j38ms_read_reg(struct j38ms_host *host, int address)
+{
+ u32 value = readl(host->addr + address);
+ dbg_reg(host, "reg 0x%02x == 0x%08x", address, value);
+ return value;
+}
+
+/* Write a register */
+static inline void j38ms_write_reg(struct j38ms_host *host,
+ int address, u32 value)
+{
+ dbg_reg(host, "reg 0x%02x <- 0x%08x", address, cpu_to_le32(value));
+ writel(value, host->addr + address);
+}
+
+/* Read a register without endiannes conversion*/
+static inline u32 j38ms_read_reg_raw(struct j38ms_host *host, int address)
+{
+ u32 value = __raw_readl(host->addr + address);
+ dbg_reg(host, "reg 0x%02x == 0x%08x", address, cpu_to_le32(value));
+ return value;
+}
+
+/* Write a register without endiannes conversion */
+static inline void j38ms_write_reg_raw(struct j38ms_host *host,
+ int address, u32 value)
+{
+ dbg_reg(host, "reg 0x%02x <- 0x%08x", address, value);
+ __raw_writel(value, host->addr + address);
+}
+
+/* Set specific bits in a register*/
+static inline void j38ms_set_reg_mask(struct j38ms_host *host,
+ int address, u32 mask)
+{
+ u32 reg = readl(host->addr + address);
+ dbg_reg(host, "reg 0x%02x |= 0x%08x (old =0x%08x)", address, mask, reg);
+ writel(reg | mask , host->addr + address);
+}
+
+/* Clear specific bits in a register*/
+static inline void j38ms_clear_reg_mask(struct j38ms_host *host,
+ int address, u32 mask)
+{
+ u32 reg = readl(host->addr + address);
+ dbg_reg(host, "reg 0x%02x &= 0x%08x (old = 0x%08x, mask = 0x%08x)",
+ address, ~mask, reg, mask);
+ writel(reg & ~mask, host->addr + address);
+}
+
+/* Reads one DWORD via PIO. returns -EAGAIN if fifo is empty */
+static inline int j38ms_read_fifo_dword_pio(struct j38ms_host *host, u32 *dword)
+{
+ if (unlikely(j38ms_read_reg(host, STATUS) & STATUS_FIFO_EMPTY)) {
+ dbg(host, "PIO: FIFO empty");
+ return -EAGAIN;
+ }
+
+ *dword = j38ms_read_reg_raw(host, DATA);
+ dbg(host, "PIO: read: %08x", *dword);
+ return 0;
+}
+
+/* Writes one DWORD via PIO. returns -EAGAIN if fifo is full */
+static inline int j38ms_write_fifo_dword_pio(struct j38ms_host *host, u32 dword)
+{
+ if (unlikely(j38ms_read_reg(host, STATUS) & STATUS_FIFO_FULL)) {
+ dbg(host, "PIO: FIFO full");
+ return -EAGAIN;
+ }
+
+ dbg(host, "PIO: writing: %08x", dword);
+ j38ms_write_reg_raw(host, DATA, dword);
+ return 0;
+}
+
+/* Read TPC data using PIO */
static unsigned int j38ms_read_fifo_pio(struct j38ms_host *host,
- unsigned char *buf, unsigned int length)
+ unsigned char *buf, unsigned int length)
{
unsigned int off = 0;
@@ -60,6 +138,7 @@ static unsigned int j38ms_read_fifo_pio(struct j38ms_host *host,
return off;
}
+/* Write TPC data through normal PIO fifo */
static unsigned int j38ms_write_fifo_pio(struct j38ms_host *host,
unsigned char *buf,
unsigned int length)
@@ -113,6 +192,7 @@ static unsigned int j38ms_write_fifo_pio(struct j38ms_host *host,
return off;
}
+/* Transfer data between current request and FIFO */
static int j38ms_transfer_data(struct j38ms_host *host)
{
unsigned int length;
@@ -180,6 +260,7 @@ static int j38ms_transfer_data(struct j38ms_host *host)
return length;
}
+/* Read short TPC data (up to 8 bytes) via 2 special registers*/
static unsigned int j38ms_read_tpc_inline(struct j38ms_host *host,
unsigned char *buf,
unsigned int length)
@@ -206,6 +287,7 @@ static unsigned int j38ms_read_tpc_inline(struct j38ms_host *host,
return off;
}
+/* Write short TPC data (up to 8 bytes) through 2 special registers */
static unsigned int j38ms_write_tpc_inline(struct j38ms_host *host,
unsigned char *buf,
unsigned int length)
@@ -232,6 +314,19 @@ static unsigned int j38ms_write_tpc_inline(struct j38ms_host *host,
return off;
}
+/*
+ * Start execution of a TPC:
+ * NOTES:
+ *
+ * PIO writes trigger wierd hardware bug that causes DMA writes
+ * to fail.
+ *
+ * length alignmemt:
+ * Short (<=8) TPC don't have any alignment problems.
+ * DMA read/writes must be 4 aligned
+ * PIO _reads_ must be aligned. Writes can be not aligned
+ *
+ */
static int j38ms_execute_tpc(struct memstick_host *msh)
{
struct j38ms_host *host = memstick_priv(msh);
@@ -330,6 +425,7 @@ static int j38ms_execute_tpc(struct memstick_host *msh)
return 0;
}
+/* Cleanups execution of current TPC */
static void j38ms_complete_tpc(struct memstick_host *msh, int last)
{
struct j38ms_host *host = memstick_priv(msh);
@@ -380,6 +476,7 @@ static void j38ms_complete_tpc(struct memstick_host *msh, int last)
}
}
+/* Interrupt handler */
static irqreturn_t j38ms_isr(int irq, void *dev_id)
{
struct memstick_host *msh = dev_id;
@@ -452,6 +549,7 @@ static irqreturn_t j38ms_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}
+/* Timer that is executed in absense of the interrupt */
static void j38ms_irq_timeout(unsigned long data)
{
struct memstick_host *msh = (struct memstick_host *)data;
@@ -496,6 +594,7 @@ static void j38ms_submit_req(struct memstick_host *msh)
tasklet_schedule(&host->notify);
}
+/* hardware reset */
static int j38ms_reset(struct j38ms_host *host)
{
int cnt;
@@ -700,6 +799,7 @@ static struct memstick_host *j38ms_alloc_host(struct j38ms *jm, int cnt)
return NULL;
host = memstick_priv(msh);
+ host->msh = msh;
host->chip = jm;
host->addr = ioremap(pci_resource_start(jm->pdev, cnt),
pci_resource_len(jm->pdev, cnt));
diff --git a/drivers/memstick/host/jmb38x_ms.h b/drivers/memstick/host/jmb38x_ms.h
index 44e1fc1..35b8bca 100644
--- a/drivers/memstick/host/jmb38x_ms.h
+++ b/drivers/memstick/host/jmb38x_ms.h
@@ -144,6 +144,7 @@
struct j38ms_host {
struct j38ms *chip;
+ struct memstick_host *msh;
void __iomem *addr;
spinlock_t lock;
struct tasklet_struct notify;
--
1.7.1
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