};
/**
+ * i40e_write_byte - replace HMC context byte
+ * @hmc_bits: pointer to the HMC memory
+ * @ce_info: a description of the struct to be read from
+ * @src: the struct to be read from
+ **/
+static void i40e_write_byte(u8 *hmc_bits,
+ struct i40e_context_ele *ce_info,
+ u8 *src)
+{
+ u8 src_byte, dest_byte, mask;
+ u8 *from, *dest;
+ u16 shift_width;
+
+ /* copy from the next struct field */
+ from = src + ce_info->offset;
+
+ /* prepare the bits and mask */
+ shift_width = ce_info->lsb % 8;
+ mask = ((u8)1 << ce_info->width) - 1;
+
+ src_byte = *from;
+ src_byte &= mask;
+
+ /* shift to correct alignment */
+ mask <<= shift_width;
+ src_byte <<= shift_width;
+
+ /* get the current bits from the target bit string */
+ dest = hmc_bits + (ce_info->lsb / 8);
+
+ memcpy(&dest_byte, dest, sizeof(dest_byte));
+
+ dest_byte &= ~mask; /* get the bits not changing */
+ dest_byte |= src_byte; /* add in the new bits */
+
+ /* put it all back */
+ memcpy(dest, &dest_byte, sizeof(dest_byte));
+}
+
+/**
+ * i40e_write_word - replace HMC context word
+ * @hmc_bits: pointer to the HMC memory
+ * @ce_info: a description of the struct to be read from
+ * @src: the struct to be read from
+ **/
+static void i40e_write_word(u8 *hmc_bits,
+ struct i40e_context_ele *ce_info,
+ u8 *src)
+{
+ u16 src_word, mask;
+ u8 *from, *dest;
+ u16 shift_width;
+ __le16 dest_word;
+
+ /* copy from the next struct field */
+ from = src + ce_info->offset;
+
+ /* prepare the bits and mask */
+ shift_width = ce_info->lsb % 8;
+ mask = ((u16)1 << ce_info->width) - 1;
+
+ /* don't swizzle the bits until after the mask because the mask bits
+ * will be in a different bit position on big endian machines
+ */
+ src_word = *(u16 *)from;
+ src_word &= mask;
+
+ /* shift to correct alignment */
+ mask <<= shift_width;
+ src_word <<= shift_width;
+
+ /* get the current bits from the target bit string */
+ dest = hmc_bits + (ce_info->lsb / 8);
+
+ memcpy(&dest_word, dest, sizeof(dest_word));
+
+ dest_word &= ~(cpu_to_le16(mask)); /* get the bits not changing */
+ dest_word |= cpu_to_le16(src_word); /* add in the new bits */
+
+ /* put it all back */
+ memcpy(dest, &dest_word, sizeof(dest_word));
+}
+
+/**
+ * i40e_write_dword - replace HMC context dword
+ * @hmc_bits: pointer to the HMC memory
+ * @ce_info: a description of the struct to be read from
+ * @src: the struct to be read from
+ **/
+static void i40e_write_dword(u8 *hmc_bits,
+ struct i40e_context_ele *ce_info,
+ u8 *src)
+{
+ u32 src_dword, mask;
+ u8 *from, *dest;
+ u16 shift_width;
+ __le32 dest_dword;
+
+ /* copy from the next struct field */
+ from = src + ce_info->offset;
+
+ /* prepare the bits and mask */
+ shift_width = ce_info->lsb % 8;
+
+ /* if the field width is exactly 32 on an x86 machine, then the shift
+ * operation will not work because the SHL instructions count is masked
+ * to 5 bits so the shift will do nothing
+ */
+ if (ce_info->width < 32)
+ mask = ((u32)1 << ce_info->width) - 1;
+ else
+ mask = -1;
+
+ /* don't swizzle the bits until after the mask because the mask bits
+ * will be in a different bit position on big endian machines
+ */
+ src_dword = *(u32 *)from;
+ src_dword &= mask;
+
+ /* shift to correct alignment */
+ mask <<= shift_width;
+ src_dword <<= shift_width;
+
+ /* get the current bits from the target bit string */
+ dest = hmc_bits + (ce_info->lsb / 8);
+
+ memcpy(&dest_dword, dest, sizeof(dest_dword));
+
+ dest_dword &= ~(cpu_to_le32(mask)); /* get the bits not changing */
+ dest_dword |= cpu_to_le32(src_dword); /* add in the new bits */
+
+ /* put it all back */
+ memcpy(dest, &dest_dword, sizeof(dest_dword));
+}
+
+/**
+ * i40e_write_qword - replace HMC context qword
+ * @hmc_bits: pointer to the HMC memory
+ * @ce_info: a description of the struct to be read from
+ * @src: the struct to be read from
+ **/
+static void i40e_write_qword(u8 *hmc_bits,
+ struct i40e_context_ele *ce_info,
+ u8 *src)
+{
+ u64 src_qword, mask;
+ u8 *from, *dest;
+ u16 shift_width;
+ __le64 dest_qword;
+
+ /* copy from the next struct field */
+ from = src + ce_info->offset;
+
+ /* prepare the bits and mask */
+ shift_width = ce_info->lsb % 8;
+
+ /* if the field width is exactly 64 on an x86 machine, then the shift
+ * operation will not work because the SHL instructions count is masked
+ * to 6 bits so the shift will do nothing
+ */
+ if (ce_info->width < 64)
+ mask = ((u64)1 << ce_info->width) - 1;
+ else
+ mask = -1;
+
+ /* don't swizzle the bits until after the mask because the mask bits
+ * will be in a different bit position on big endian machines
+ */
+ src_qword = *(u64 *)from;
+ src_qword &= mask;
+
+ /* shift to correct alignment */
+ mask <<= shift_width;
+ src_qword <<= shift_width;
+
+ /* get the current bits from the target bit string */
+ dest = hmc_bits + (ce_info->lsb / 8);
+
+ memcpy(&dest_qword, dest, sizeof(dest_qword));
+
+ dest_qword &= ~(cpu_to_le64(mask)); /* get the bits not changing */
+ dest_qword |= cpu_to_le64(src_qword); /* add in the new bits */
+
+ /* put it all back */
+ memcpy(dest, &dest_qword, sizeof(dest_qword));
+}
+
+/**
* i40e_clear_hmc_context - zero out the HMC context bits
* @hw: the hardware struct
* @context_bytes: pointer to the context bit array (DMA memory)
struct i40e_context_ele *ce_info,
u8 *dest)
{
- u16 shift_width;
- u64 bitfield;
- u8 hi_byte;
- u8 hi_mask;
- u64 t_bits;
- u64 mask;
- u8 *p;
int f;
for (f = 0; ce_info[f].width != 0; f++) {
- /* clear out the field */
- bitfield = 0;
- /* copy from the next struct field */
- p = dest + ce_info[f].offset;
+ /* we have to deal with each element of the HMC using the
+ * correct size so that we are correct regardless of the
+ * endianness of the machine
+ */
switch (ce_info[f].size_of) {
case 1:
- bitfield = *p;
+ i40e_write_byte(context_bytes, &ce_info[f], dest);
break;
case 2:
- bitfield = cpu_to_le16(*(u16 *)p);
+ i40e_write_word(context_bytes, &ce_info[f], dest);
break;
case 4:
- bitfield = cpu_to_le32(*(u32 *)p);
+ i40e_write_dword(context_bytes, &ce_info[f], dest);
break;
case 8:
- bitfield = cpu_to_le64(*(u64 *)p);
+ i40e_write_qword(context_bytes, &ce_info[f], dest);
break;
}
-
- /* prepare the bits and mask */
- shift_width = ce_info[f].lsb % 8;
- mask = ((u64)1 << ce_info[f].width) - 1;
-
- /* save upper bytes for special case */
- hi_mask = (u8)((mask >> 56) & 0xff);
- hi_byte = (u8)((bitfield >> 56) & 0xff);
-
- /* shift to correct alignment */
- mask <<= shift_width;
- bitfield <<= shift_width;
-
- /* get the current bits from the target bit string */
- p = context_bytes + (ce_info[f].lsb / 8);
- memcpy(&t_bits, p, sizeof(u64));
-
- t_bits &= ~mask; /* get the bits not changing */
- t_bits |= bitfield; /* add in the new bits */
-
- /* put it all back */
- memcpy(p, &t_bits, sizeof(u64));
-
- /* deal with the special case if needed
- * example: 62 bit field that starts in bit 5 of first byte
- * will overlap 3 bits into byte 9
- */
- if ((shift_width + ce_info[f].width) > 64) {
- u8 byte;
-
- hi_mask >>= (8 - shift_width);
- hi_byte >>= (8 - shift_width);
- byte = p[8] & ~hi_mask; /* get the bits not changing */
- byte |= hi_byte; /* add in the new bits */
- p[8] = byte; /* put it back */
- }
}
return 0;